0001451505-26-000018 | 10-K | XBRL Viewer

Debt (Details) - USD ($) $ in Millions	Dec. 31, 2025	Oct. 31, 2025	Dec. 31, 2024	Jun. 30, 2024	Apr. 30, 2024	Dec. 31, 2023	Oct. 31, 2023	Jan. 31, 2023
Principal amount
Total principal amount of debt	$ 5,686		$ 6,944
Debt due within one year	458		714
Long-term debt	5,228		6,230
Carrying amount
Total debt	5,657		6,881
Debt due within one year	445		686
Long-term debt	$ 5,212		6,195
4.00% Senior Guaranteed Exchangeable Bonds due December 2025
Principal amount
Total principal amount of debt			234
Debt due within one year			234
Carrying amount
Total debt			227
Debt due within one year			227
Debt instrument interest rate stated percentage	4.00%					4.00%	4.00%
6.875% Senior Secured Notes due February 2027
Principal amount
Total principal amount of debt			330
Debt due within one year			83
Carrying amount
Total debt			328
Debt due within one year			82
Debt instrument interest rate stated percentage	6.875%
8.00% Senior Notes due February 2027
Principal amount
Total principal amount of debt			655
Carrying amount
Total debt			$ 653
Debt instrument interest rate stated percentage	8.00%		8.00%	8.00%
7.45% Notes due April 2027
Principal amount
Total principal amount of debt	$ 52		$ 52
Carrying amount
Total debt	$ 52		52
Debt instrument interest rate stated percentage	7.45%
8.00% Debentures due April 2027
Principal amount
Total principal amount of debt	$ 22		22
Carrying amount
Total debt	$ 22		22
Debt instrument interest rate stated percentage	8.00%
4.50% Shipyard Loans due September 2027
Principal amount
Total principal amount of debt	$ 209		329
Debt due within one year	136		120
Carrying amount
Total debt	202		310
Debt due within one year	$ 129		108
Debt instrument interest rate stated percentage	4.50%
8.375% Senior Secured Notes due February 2028
Principal amount
Total principal amount of debt	$ 425		525
Debt due within one year	135		100
Carrying amount
Total debt	421		518
Debt due within one year	$ 133		97
Debt instrument interest rate stated percentage	8.375%							8.375%
7.00% Notes due June 2028
Principal amount
Total principal amount of debt	$ 209		261
Carrying amount
Total debt	$ 210		263
Debt instrument interest rate stated percentage	7.00%
8.00% Senior Secured Notes due September 2028
Principal amount
Total principal amount of debt	$ 235		295
Debt due within one year	70		60
Carrying amount
Total debt	233		292
Debt due within one year	$ 69		59
Debt instrument interest rate stated percentage	8.00%
8.25% Senior Notes due May 2029
Principal amount
Total principal amount of debt	$ 900		900
Carrying amount
Total debt	$ 889		887
Debt instrument interest rate stated percentage	8.25%				8.25%
4.625% Senior Guaranteed Exchangeable Bonds due September 2029
Principal amount
Total principal amount of debt	$ 259		259
Carrying amount
Total debt	$ 292		286
Debt instrument interest rate stated percentage	4.625%					4.625%	4.625%
8.75% Senior Secured Notes due February 2030
Principal amount
Total principal amount of debt	$ 881		999
Debt due within one year	117		117
Carrying amount
Total debt	868		981
Debt due within one year	$ 114		113
Debt instrument interest rate stated percentage	8.75%							8.75%
7.50% Notes due April 2031
Principal amount
Total principal amount of debt	$ 396		396
Carrying amount
Total debt	$ 395		395
Debt instrument interest rate stated percentage	7.50%
8.50% Senior Notes due May 2031
Principal amount
Total principal amount of debt	$ 900		900
Carrying amount
Total debt	$ 888		886
Debt instrument interest rate stated percentage	8.50%				8.50%
7.875% Senior Guaranteed Notes due October 2032
Principal amount
Total principal amount of debt	$ 500
Carrying amount
Total debt	$ 493
Debt instrument interest rate stated percentage	7.875%	7.875%
6.80% Senior Notes due March 2038
Principal amount
Total principal amount of debt	$ 610		610
Carrying amount
Total debt	$ 605		605
Debt instrument interest rate stated percentage	6.80%
7.35% Senior Notes due December 2041
Principal amount
Total principal amount of debt	$ 88		177
Carrying amount
Total debt	$ 87		$ 176
Debt instrument interest rate stated percentage	7.35%

Pay vs Performance Disclosure - USD ($) $ in Millions	12 Months Ended
Pay vs Performance Disclosure - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Pay vs Performance Disclosure
Net Income (Loss)	$ (2,915)	$ (512)	$ (954)

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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+ Details

Unconsolidated Affiliates

12 Months Ended

Dec. 31, 2025

Unconsolidated Affiliates

Unconsolidated Affiliates

Note 4—Unconsolidated Affiliates

Equity investments

Overview—At December 31, 2025, we hold equity investments in certain unconsolidated companies, including (a) our 16 percent ownership interest in Global Sea Mineral Resources NV (together with its subsidiaries, “GSR”), a Belgian company and leading developer of nodule collection technology, which is engaged in the development and exploration of deep-sea polymetallic nodules that contain metals critical to the growing renewable energy market, (b) our 19 percent ownership interest in Ocean Minerals LLC, the parent company of Moana Minerals Ltd., a Cook Islands subsea resource development company that intends to explore and collect polymetallic nodules, and (c) our ownership interests in other companies involved in researching and developing technology to improve efficiency, reliability, sustainability and safety for drilling and other activities. In the years ended December 31, 2025, 2024 and 2023, we recognized income of $1 million, income of $4 million and a loss of $14 million, respectively, recorded in other, net, associated with equity in earnings or losses of our equity investments. At December 31, 2025 and 2024, the aggregate carrying amount of our equity investments was $121 million and $123 million, respectively, recorded in other assets.

Contributions—In February 2023, we acquired a noncontrolling interest in GSR in exchange for a cash contribution of $10 million and a non-cash contribution of the ultra-deepwater floater Ocean Rig Olympia, which had been cold stacked, and related assets, with an estimated fair value of $85 million (see Note 6—Long-Lived Assets). We estimated the fair value of the rig using projected discounted cash flows, and our estimate required us to use significant unobservable inputs, representative of Level 3 fair value measurements, including assumptions related to future performance of the rig, projected demand for its services, rig availability and dayrates.

Acquisition—In June 2024, we acquired the outstanding 67.0 percent ownership interest in Orion Holdings (Cayman) Limited (together with its subsidiary, “Orion”), the Cayman Islands company that owned the harsh environment floater Transocean Norge, in a noncash transaction. Prior to this transaction, we held a 33.0 percent noncontrolling interest in Orion and the aggregate carrying amount of our investment was $86 million. To acquire Orion, we issued 55.5 million Transocean Ltd. shares and $130 million aggregate principal amount of 8.00% senior notes due February 2027 (the “8.00% Senior Notes”) with an aggregate fair value of $431 million. As a result, Orion became our wholly owned subsidiary. We recorded the transaction using the asset acquisition method of accounting. See Note 6—Long Lived Assets, Note 8—Debt and Note 13—Equity.

Impairments—In the year ended December 31, 2024, we recognized a loss of $5 million, which had no tax effect, recorded in other, net, associated with the other-than-temporary impairment of the carrying amount of certain equity investments.

Related party transactions

Acquisition—In September 2023, we acquired the outstanding ownership interest in Liquila Ventures Ltd. (together with its subsidiaries, “Liquila”), a previously unconsolidated Bermuda company, that was constructing the ultra-deepwater floater Deepwater Aquila. Prior to this transaction, we and Perestroika (Cyprus) Ltd (together with its subsidiaries, “Perestroika”), an entity affiliated with one of our directors that beneficially owns approximately nine percent of our shares, held a noncontrolling interest of 20 percent and 13 percent, respectively, in Liquila. To acquire the outstanding 80 percent ownership interest in Liquila, we issued 11.9 million Transocean Ltd. shares with an aggregate value of $99 million, including 2.0 million Transocean Ltd. shares with an aggregate value of $16 million issued to Perestroika. As a result, Liquila became our wholly owned subsidiary. We recorded the transaction using the asset acquisition method of accounting. See Note 6—Long Lived Assets and Note 13—Equity.

Operating and lending activities—We procure and provide services and equipment from and to our unconsolidated affiliates for technological innovation and subsea minerals exploration, and we occasionally provide loans to our unconsolidated affiliates. In the years ended December 31, 2025, 2024 and 2023, we made an aggregate cash payment of $12 million, $14 million and $12 million, respectively, to our unconsolidated affiliates primarily for equipment and for research and development. At December 31, 2025 and 2024, the aggregate carrying amount of balances due to us under certain financing arrangements with our unconsolidated affiliates was $8 million and $10 million, respectively, recorded in other assets.

In the years ended December 31, 2024 and 2023, we received an aggregate cash payment of $11 million and $49 million, respectively, for services and equipment provided to, and prior to our acquisition of, Orion. In the years ended December 31, 2024, and 2023, we recognized rent expense of $25 million and $26 million, respectively, recorded in operating and maintenance costs, and made an aggregate cash payment of $25 million and $27 million, respectively, to charter the rig and rent other equipment from, and prior to our acquisition of, Orion. Additionally, in the year ended December 31, 2023, we and Orion agreed to the non-cash net settlement of a balance of $25 million of accounts receivable and payable.

Leases (Operating leases) (Details)	Dec. 31, 2025
Leases
Weighted average discount rate, operating leases (as a percent)	7.30%
Weighted-average remaining lease term, operating leases	9 years 10 months 24 days

Document and Entity Information - USD ($) $ in Millions	12 Months Ended
Document and Entity Information - USD ($) $ in Millions	Dec. 31, 2025	Feb. 17, 2026	Jun. 30, 2025
Document and Entity Information
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2025
Current Fiscal Year End Date	--12-31
Document Transition Report	false
Securities Act File Number	001-38373
Entity Registrant Name	TRANSOCEAN LTD
Entity Incorporation, State or Country Code	V8
Entity Tax Identification Number	98-0599916
Entity Address, Address Line One	Turmstrasse 30
Entity Address, City or Town	Steinhausen
Entity Address, Country	CH
Entity Address, Postal Zip Code	6312
City Area Code	+41 (41)
Local Phone Number	749-0500
Title of 12(b) Security	Shares, $0.10 par value
Trading Symbol	RIG
Security Exchange Name	NYSE
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Document Financial Statement Error Correction [Flag]	false
Entity Shell Company	false
Entity Public Float			$ 2,340
Entity Common Stock, Shares Outstanding		1,102,848,748
Entity Central Index Key	0001451505
Document Fiscal Year Focus	2025
Document Fiscal Period Focus	FY
Amendment Flag	false
Auditor Name	Ernst & Young LLP
Auditor Firm ID	42
Auditor Location	Houston, Texas
Documents Incorporated by Reference [Text Block]	Portions of the registrant’s definitive Proxy Statement to be filed with the United States Securities and Exchange Commission within 120 days of December 31, 2025, for its 2026 annual general meeting of shareholders, are incorporated by reference into Part III of this Form 10-K.

Share-Based Compensation (Restricted Share Units) (Details) - Restricted shares - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Service awards
Equity instruments other than options activity
Outstanding at the beginning of the period (in shares)	7,659,028
Granted (in shares)	6,852,828	5,116,762	3,744,049
Vested (in shares)	5,280,936	6,727,943	6,200,155
Forfeited (in shares)	(113,268)
Outstanding at the end of the period (in shares)	9,117,652	7,659,028
Weighted-average grant-date fair value per share
Outstanding at the beginning of the period (in dollars per share)	$ 5.44
Granted (in dollars per share)	3.47	$ 5.29	$ 7.23
Vested (in dollars per share)	4.72
Forfeited (in dollars per share)	4.46
Outstanding at the end of the period (in dollars per share)	$ 4.23	$ 5.44
Additional disclosure
Total grant date fair value	$ 25	$ 32	$ 18
Performance awards
Equity instruments other than options activity
Outstanding at the beginning of the period (in shares)	3,495,925
Granted (in shares)	3,138,657	2,687,268	1,912,292
Vested (in shares)	1,439,846	4,429,028	3,025,512
Outstanding at the end of the period (in shares)	5,194,736	3,495,925
Weighted-average grant-date fair value per share
Outstanding at the beginning of the period (in dollars per share)	$ 5.78
Granted (in dollars per share)	3.35	$ 5.1	$ 6.74
Vested (in dollars per share)	6.74
Outstanding at the end of the period (in dollars per share)	$ 4.04	$ 5.78
Additional disclosure
Total grant date fair value	$ 10	$ 21	$ 11

Supplemental Balance Sheet Information (Tables)

12 Months Ended

Dec. 31, 2025

Supplemental Balance Sheet Information

Schedule of other current liabilities

Other current liabilities were comprised of the following (in millions):


		December 31,
		2025			2024
Other current liabilities
Accrued employee benefits and payroll-related liabilities		$	166		$	136
Accrued interest			101			134
Accrued taxes, other than income			28			39
Finance lease liability			51			47
Operating lease liabilities			8			7
Contract liabilities			181			231
Contingent liabilities			87			94
Other			5			3
Total other current liabilities		$	627		$	691

Schedule of other long term liabilities

Other long-term liabilities were comprised of the following (in millions):


		December 31,
		2025			2024
Other long-term liabilities
Postemployment benefit plan obligations		$	103		$	100
Finance lease liability			169			224
Operating lease liabilities			86			88
Income taxes payable			90			65
Contract liabilities			92			212
Other			42			40
Total other long-term liabilities		$	582		$	729

Long-Lived Assets (Disposals) (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	12 Months Ended
	Jan. 31, 2026	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Disposals
Gain (loss) on the sale of assets		$ 7.0	$ (17.0)	$ (183.0)
Proceeds from disposal of assets, net of costs to sell		84.0	101.0	10.0
Cash deposits received for the sale of assets		3.0
Assets sold, not discontinued operations \| Rig sales
Disposals
Deposit received			6.0
Gain (loss) on the sale of assets		4.0		$ (169.0)
Proceeds from disposal of assets, net of costs to sell		71.0	102.0
Gain (loss) on the sale of assets per diluted share				$ (0.22)
Gain (loss) on disposal of assets, tax effect		0.0		$ 0.0
Assets sold, not discontinued operations \| Other property and equipment
Disposals
Gain (loss) on the sale of assets		3.0	(17.0)	(14.0)
Proceeds from disposal of assets, net of costs to sell		10.0	$ 5.0	$ 4.0
Ultra-deepwater drillships \| Assets sold, not discontinued operations \| Rig sales
Disposals
Cash deposits received for the sale of assets		$ 1.0
Ultra-deepwater drillships \| Assets sold, not discontinued operations \| Rig sales \| Subsequent Event
Disposals
Proceeds from disposal of assets, net of costs to sell	$ 14.0

Commitments and Contingencies (Legal Proceedings) (Details) - Asbestos litigation	12 Months Ended
	Dec. 31, 2025 lawsuit USD ($)
Contingencies
Number of claims \| lawsuit	405
LOUISIANA
Contingencies
Number of plaintiffs	2
Illinois, Missouri or California
Contingencies
Number of plaintiffs	30

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 275
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-Section 50
-Paragraph 9
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-URI https://asc.fasb.org/1943274/2147482861/275-10-50-9

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+ Details

Debt (Maturities) (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Scheduled maturities of debt
Total principal amount of debt	$ 5,686	$ 6,944
Total installments
Scheduled maturities of debt
2026	458
2027	435
2028	612
2029	1,277
2030	411
Thereafter	2,493
Total principal amount of debt	5,686
Total unamortized debt-related balances, net	(155)
Bifurcated compound exchange feature, at estimated fair value	126
Total carrying amount of debt	$ 5,657

Share-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2025

Share Based Compensation

Summary of activity for vested and unvested stock options outstanding

The following table summarizes activity during the year ended December 31, 2025 for vested service-based stock options outstanding under our incentive plan:


							Weighted-average
		Number		Weighted-average			remaining		Aggregate
		of shares		exercise price			contractual term		intrinsic value
		under option		per share			(years)		(in millions)
Outstanding at January 1, 2025		4,069,334		$	9.53		2.93		$	—
Forfeited		(17,006)			8.35
Outstanding at December 31, 2025		4,052,328		$	9.54		1.92		$	—

Vested and exercisable at December 31, 2025		4,052,328		$	9.54		1.92		$	—

Service awards

Share Based Compensation

Summary of unvested deferred units activity

The following table summarizes unvested activity during the year ended December 31, 2025 for service-based units granted under our incentive plan:


		Number		Weighted-average
		of		grant-date fair value
		units		per unit
Unvested at January 1, 2025		7,659,028		$	5.44
Granted		6,852,828			3.47
Vested		(5,280,936)			4.72
Forfeited		(113,268)			4.46
Unvested at December 31, 2025		9,117,652		$	4.23

Performance awards

Share Based Compensation

Summary of unvested deferred units activity

The following table summarizes unvested activity during the year ended December 31, 2025 for performance-based units under our incentive plan:


		Number		Weighted-average
		of		grant-date fair value
		units		per unit
Unvested at January 1, 2025		3,495,925		$	5.78
Granted		3,138,657			3.35
Vested		(1,439,846)			6.74
Unvested at December 31, 2025		5,194,736		$	4.04

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details

Debt (Exchangeable) (Details) $ / shares in Units, shares in Millions, $ in Millions		1 Months Ended			12 Months Ended
	Mar. 30, 2026	Oct. 31, 2023 USD ($) shares	Jul. 31, 2023 USD ($) shares	Apr. 30, 2023 USD ($) shares	Dec. 31, 2025 USD ($) $ / shares shares	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($) shares
Debt
Aggregate principal amount of debt retired					$ 1,045.0	$ 1,697.0
Shares issuable (in shares)					201.0		434.0
Shares issued upon conversion (in shares) \| shares					73.3		65.1
Aggregate principal amount of debt issued in exchanges							$ 434.0
Loss on conversion of debt to equity					$ 99.0		$ 27.0
Aggregate principal amount outstanding					$ 5,686.0	6,944.0
2.50% Senior Guaranteed Exchangeable Bonds due January 2027
Debt
Debt instrument interest rate stated percentage			2.50%				2.50%
Debt conversion ratio							0.1621626
Shares issued upon conversion (in shares) \| shares			4.0	34.6
Cash consideration on conversion of debt				$ 3.0
Aggregate principal amount of debt issued in exchanges			$ 25.0	$ 213.0			$ 238.0
Loss on conversion of debt to equity							$ 3.0
4.00% Senior Guaranteed Exchangeable Bonds due December 2025
Debt
Debt instrument interest rate stated percentage		4.00%			4.00%		4.00%
Debt conversion ratio		0.1904762
Shares issued upon conversion (in shares) \| shares					73.3
Aggregate principal amount of debt issued in exchanges		$ 60.0			$ 196.0
Loss on conversion of debt to equity					$ 99.0
Aggregate principal amount outstanding						234.0
4.00% Senior Guaranteed Exchangeable Bonds due December 2025 \| Incremental portion pursuant to governing indenture
Debt
Shares issued upon conversion (in shares) \| shares					35.9
4.625% Senior Guaranteed Exchangeable Bonds due September 2029
Debt
Aggregate principal amount of debt retired							$ 41.0
Debt instrument interest rate stated percentage		4.625%			4.625%		4.625%
Debt conversion ratio		0.2906618			0.2906618
Debt conversion (in dollars per share) \| $ / shares					$ 3.44
Shares issuable (in shares)					75.3
Effective interest rate (as a percent)					18.30%
Aggregate principal amount of debt issued in exchanges		$ 41.0
Fair value of debt					$ 355.0
Bifurcated compound exchange feature, at estimated fair value					126.0	136.0
Aggregate principal amount outstanding					259.0	$ 259.0
4.625% Senior Guaranteed Exchangeable Bonds due September 2029 \| Plan
Debt
Amount to repurchase upon the occurrence of certain events (as a percent)	1.15
Trading days for calculation of average stock price	20 days
Debt instrument interest rate stated percentage	4.625%
Senior Guaranteed Exchangeable 4.00% Senior Guaranteed Exchangeable Bonds due December 2025 and Bonds 4.625 Percent Due September 2029
Debt
Shares issued upon conversion (in shares) \| shares		26.5
Loss on conversion of debt to equity							$ 24.0
Shares issued in exchange (in shares) \| shares		3.1
Senior Secured Notes
Debt
Aggregate carrying amount assets pledged					$ 5,190.0

Long-Lived Assets

12 Months Ended

Dec. 31, 2025

Long-Lived Assets.

Long-Lived Assets

Note 6—Long-Lived Assets

Disaggregation—The aggregate carrying amount of our long-lived assets, including our property and equipment and our right-of-use assets, measured net of accumulated depreciation or amortization, disaggregated by country in which they were located, was as follows (in millions):


	December 31,
	2025		2024
Long-lived assets
U.S.	$	6,487	$	6,727
Norway		1,941		2,017
Brazil		1,914		1,993
Greece		611		2,531
Other countries (a)		2,050		3,008
Total long-lived assets	$	13,003	$	16,276

(a)

The aggregate net carrying amount of long-lived assets located in other countries that individually represented less than 10 percent of total long-lived assets on both dates.

Because the majority of our assets are mobile, the geographic locations of such assets at the end of the periods are not necessarily indicative of the geographic distribution of the operating revenues generated by such assets during the periods presented. Our international operations are subject to certain political and other uncertainties, including risks of war and civil disturbances or other market disrupting events, expropriation of equipment, repatriation of income or capital, taxation policies, and the general hazards associated with certain areas in which we operate. Although we are organized under the laws of Switzerland, we have minimal assets located in Switzerland, and we do not conduct any operations or earn operating revenues in Switzerland.

Property and equipment—At December 31, 2025 and 2024, our rigs and related equipment, measured at cost, had a carrying amount of $17.1 billion and $22.0 billion, respectively, representing 98 percent of our total property and equipment, measured at cost. In the years ended December 31, 2024 and 2023, we capitalized interest costs of $15 million and $39 million, respectively, for our construction work in progress.

Acquisitions—In June 2024 we acquired $517 million of property and equipment associated with Transocean Norge, together with $5 million of cash and cash equivalents and $4 million of accounts receivable from us. In September 2023, we acquired $126 million of property and equipment associated with Deepwater Aquila, together with $7 million of cash and cash equivalents, and we assumed $19 million of accounts payable. See Note 4—Unconsolidated Affiliates, Note 8—Debt and Note 13—Equity.

Impairments—In the year ended December 31, 2025, we recognized an aggregate loss of $3.05 billion ($3.04 billion, or $3.16 per diluted share, net of tax), respectively, associated with the impairment of the ultra-deepwater floaters Deepwater Champion, Discoverer Americas, Discoverer Clear Leader, Discoverer India, Discoverer Luanda, GSF Development Driller I and the harsh environment semisubmersible Henry Goodrich, together with related assets, which we determined were impaired at the time that we classified the assets as held for sale, and the ultra-deepwater floaters Development Driller III and Discoverer Inspiration, together with related assets, which were previously classified as held for sale and we determined were further impaired. In the year ended December 31, 2024, we recognized a loss of $772 million ($755 million or $0.82 per diluted share, net of tax) associated with the impairment of the ultra-deepwater floaters Deepwater Nautilus, Development Driller III and Discoverer Inspiration, together with related assets, which we determined were impaired at the time that we classified the assets as held for sale. In the year ended December 31, 2023, we recognized a loss of $57 million ($0.07 per diluted share), which had no tax effect, associated with the impairment of the harsh environment floaters Paul B. Loyd, Jr. and Transocean Leader, together with related assets, which we determined were impaired at the time that we classified the assets as held for sale.

We measured the impairment of the rigs and related assets as the amount by which the carrying amount exceeded the estimated fair value less costs to sell. We estimated the fair value of the assets using significant other observable inputs, representative of Level 2 fair value measurements, including binding contracts for the sale of the rigs and related assets or indicative market values for the assets to be sold for recycling or scrap.

Assets held for sale—At December 31, 2025, the aggregate carrying amount of our assets held for sale, including Deepwater Champion, Discoverer India and Henry Goodrich, together with related assets, was $24 million, and in the year ended December 31, 2025, we received an aggregate cash deposit of $3 million for the sale of the two drillships. At December 31, 2024, the aggregate carrying amount of our assets held for sale, including Development Driller III and Discoverer Inspiration, together with related assets, was $343 million.

Disposals—In the year ended December 31, 2025, we completed the sale of Development Driller III, Discoverer Americas, Discoverer Clear Leader, Discoverer Inspiration, Discoverer Luanda and GSF Development Driller I, together with related assets, for aggregate net cash proceeds of $71 million, and we recognized an aggregate net gain of $4 million, which had no tax effect, associated with the disposal of the rigs and related assets. In the year ended December 31, 2024, we completed the sale of Deepwater Nautilus, Paul B. Loyd, Jr. and Transocean Leader, together with related assets, for aggregate net cash proceeds of $102 million, including $6 million received as a deposit in the year ended December 31, 2023. In the year ended December 31, 2023, we made a non-cash contribution of Ocean Rig Olympia and related assets in connection with our investment in a partial ownership interest in GSR, and we recognized a loss of $169 million ($0.22 per diluted share), which had no tax effect, associated with the disposal of the rig and related assets (see Note 4—Unconsolidated Affiliates). In the years ended December 31, 2025, 2024 and 2023, we received aggregate net cash proceeds of $10 million, $5 million and $4 million, respectively and recognized an aggregate net gain of $3 million, an aggregate net loss of $17 million and an aggregate net loss of $14 million, respectively, associated with the disposal of assets unrelated to rig sales.

Subsequent event—In January 2026, we completed the sale of Discoverer India, together with related assets, for aggregate net cash proceeds of $14 million, including $1 million received as a deposit in the year ended December 31, 2025.

Benefit Plans (Defined Benefit Pension and Other Postemployment Benefit Plans Funded Status) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Change in projected benefit obligation
Projected benefit obligation, beginning of period	$ 1,405	$ 1,544
Actuarial (gains) losses, net	3	(122)
Interest cost	77	72	$ 74
Currency exchange rate (gain) loss	14	(2)
Benefits paid	(90)	(89)
Settlements	(1)
Special termination benefits		2
Projected benefit obligation, end of period	1,408	1,405	1,544
Change in plan assets
Fair value of plan assets, beginning of period	1,374	1,450
Actual return (loss) on plan assets	74	14
Currency exchange rate gain (loss)	16	(3)
Employer contributions	8	2	8
Benefits paid	(90)	(89)
Settlements	(1)
Fair value of plan assets, end of period	1,381	1,374	1,450
Funded status, asset (liability), end of period	(27)	(31)
Balance sheet classification, end of period:
Pension asset, non-current	78	73
Pension liability, current	(2)	(4)
Pension liability, non-current	(103)	(100)
Accumulated other comprehensive loss (income), before taxes	196	189
Accumulated benefit obligation, end of period	1,408	1,405
Projected benefit obligation in excess of plan assets
Projected benefit obligation	110	110
Fair value of plan assets	5	6
Accumulated other comprehensive loss (income) that have not been recognized
Actuarial (gain) loss, net	195	191
Prior service cost (credit), net	1	(2)
Accumulated other comprehensive loss (income), before taxes	$ 196	$ 189
Transocean Plans \| UNITED STATES
Weighted average assumptions
Discount rate (as a percent)	5.65%	5.58%
Change in projected benefit obligation
Projected benefit obligation, beginning of period	$ 1,217	$ 1,328
Actuarial (gains) losses, net	5	(97)
Interest cost	67	63	65
Benefits paid	(78)	(77)
Settlements	(1)
Projected benefit obligation, end of period	1,210	1,217	1,328
Change in plan assets
Fair value of plan assets, beginning of period	1,164	1,211
Actual return (loss) on plan assets	66	30
Employer contributions	7
Benefits paid	(78)	(77)
Settlements	(1)
Fair value of plan assets, end of period	1,158	1,164	1,211
Funded status, asset (liability), end of period	(52)	(53)
Balance sheet classification, end of period:
Pension asset, non-current	44	41
Pension liability, current		(1)
Pension liability, non-current	(96)	(93)
Accumulated other comprehensive loss (income), before taxes	112	102
Accumulated benefit obligation, end of period	1,210	1,217
Projected benefit obligation in excess of plan assets
Projected benefit obligation	101	100
Fair value of plan assets	5	6
Accumulated other comprehensive loss (income) that have not been recognized
Actuarial (gain) loss, net	112	102
Accumulated other comprehensive loss (income), before taxes	$ 112	$ 102
Transocean Plans \| UNITED KINGDOM
Weighted average assumptions
Discount rate (as a percent)	5.60%	5.60%
Change in projected benefit obligation
Projected benefit obligation, beginning of period	$ 178	$ 208
Actuarial (gains) losses, net	(2)	(27)
Interest cost	10	9	9
Currency exchange rate (gain) loss	14	(2)
Benefits paid	(11)	(10)
Projected benefit obligation, end of period	189	178	208
Change in plan assets
Fair value of plan assets, beginning of period	210	239
Actual return (loss) on plan assets	8	(16)
Currency exchange rate gain (loss)	16	(3)
Benefits paid	(11)	(10)
Fair value of plan assets, end of period	223	210	239
Funded status, asset (liability), end of period	34	32
Balance sheet classification, end of period:
Pension asset, non-current	34	32
Accumulated other comprehensive loss (income), before taxes	84	88
Accumulated benefit obligation, end of period	189	178
Accumulated other comprehensive loss (income) that have not been recognized
Actuarial (gain) loss, net	83	87
Prior service cost (credit), net	1	1
Accumulated other comprehensive loss (income), before taxes	$ 84	$ 88
OPEB Plans
Weighted average assumptions
Discount rate (as a percent)	4.34%	5.02%
Change in projected benefit obligation
Projected benefit obligation, beginning of period	$ 10	$ 8
Actuarial (gains) losses, net		2
Benefits paid	(1)	(2)
Special termination benefits		2
Projected benefit obligation, end of period	9	10	$ 8
Change in plan assets
Employer contributions	1	2
Benefits paid	(1)	(2)
Funded status, asset (liability), end of period	(9)	(10)
Balance sheet classification, end of period:
Pension liability, current	(2)	(3)
Pension liability, non-current	(7)	(7)
Accumulated other comprehensive loss (income), before taxes		(1)
Accumulated benefit obligation, end of period	9	10
Projected benefit obligation in excess of plan assets
Projected benefit obligation	$ 9	10
Accumulated other comprehensive loss (income) that have not been recognized
Actuarial (gain) loss, net		2
Prior service cost (credit), net		(3)
Accumulated other comprehensive loss (income), before taxes		$ (1)

Benefit Plans

12 Months Ended

Dec. 31, 2025

Benefit Plans

Benefit Plans

Note 9—Benefit Plans

Defined contribution plans

We sponsor defined contribution plans for our employees in most markets in which we operate worldwide, the most significant of which were as follows: (1) a qualified savings plan covering certain eligible employees working in the U.S., (2) various savings plans covering eligible employees working in Norway and (3) a non-qualified savings plan covering certain eligible expatriate employees. In the years ended December 31, 2025, 2024 and 2023, we recognized expense of $62 million, $63 million and $58 million, respectively, related to our defined contribution plans and recorded in the same financial statement line item as cash compensation paid to the respective employees.

Defined benefit pension and other postemployment benefit plans

Overview—As of December 31, 2025, we had three funded and three unfunded defined benefit plans in the U.S. (the “U.S. Plans”) and one funded defined benefit plan in the United Kingdom (the “U.K. Plan”). We also maintain certain unfunded other postemployment benefit plans (collectively, the “OPEB Plans”), under which benefits to eligible participants diminish during a phase-out period ending December 31, 2026. We maintain the benefit obligations under our defined benefit plans until they are fully satisfied.

We estimated our net periodic benefit costs using the following weighted average assumptions:


		Year ended December 31, 2025						Year ended December 31, 2024						Year ended December 31, 2023
		U.S.		U.K.		OPEB		U.S.		U.K.		OPEB		U.S.		U.K.		OPEB
		Plans		Plan		Plans		Plans		Plan		Plans		Plans		Plan		Plans
Discount rate		5.58	%	5.60	%	5.02	%	4.88	%	4.50	%	4.80	%	5.06	%	4.80	%	4.92	%
Expected rate of return		5.66	%	4.80	%	na		6.51	%	5.10	%	na		6.41	%	5.00	%	na

“na” means not applicable.

We estimated our benefit obligations using the following weighted-average assumptions:

December 31, 2025

December 31, 2024

U.S.

U.K.

OPEB

U.S.

U.K.

OPEB

Plans

 

Plan

 

Plans

 

Plans

 

Plan

 

Plans

Discount rate

5.65

5.60

4.34

5.58

5.60

5.02

Net periodic benefit costs—The components of net periodic benefit costs, recognized in other income and expense, were as follows (in millions):


	Year ended December 31, 2025								Year ended December 31, 2024								Year ended December 31, 2023
	U.S.		U.K.		OPEB				U.S.		U.K.		OPEB				U.S.		U.K.		OPEB
	Plans		Plan		Plans		Total		Plans		Plan		Plans		Total		Plans		Plan		Plans		Total
Net periodic benefit costs
Interest cost	$	67	$	10	$	—	$	77	$	63	$	9	$	—	$	72	$	65	$	9	$	—	$	74
Expected return on plan assets		(71)		(9)		—		(80)		(86)		(11)		—		(97)		(84)		(11)		—		(95)
Special termination benefits		—		—		—		—		—		—		2		2		—		—		—		—
Settlements and curtailments		—		—		—		—		—		—		(2)		(2)		—		—		—		—
Actuarial loss, net		—		3		—		3		1		2		—		3		—		2		—		2
Prior service gain, net		—		—		(1)		(1)		—		—		(1)		(1)		—		—		(2)		(2)
Net periodic benefit costs (income)	$	(4)	$	4	$	(1)	$	(1)	$	(22)	$	—	$	(1)	$	(23)	$	(19)	$	—	$	(2)	$	(21)

Funded status—The changes in funded status were as follows (in millions):


		Year ended December 31, 2025												Year ended December 31, 2024
		U.S.			U.K.			OPEB						U.S.			U.K.			OPEB
		Plans			Plan			Plans			Total			Plans			Plan			Plans			Total
Change in projected benefit obligation
Projected benefit obligation, beginning of period		$	1,217		$	178		$	10		$	1,405		$	1,328		$	208		$	8		$	1,544
Actuarial (gain) loss, net			5			(2)			—			3			(97)			(27)			2			(122)
Interest cost			67			10			—			77			63			9			—			72
Currency exchange rate (gain) loss			—			14			—			14			—			(2)			—			(2)
Benefits paid			(78)			(11)			(1)			(90)			(77)			(10)			(2)			(89)
Settlements			(1)			—			—			(1)			—			—			—			—
Special termination benefits			—			—			—			—			—			—			2			2
Projected benefit obligation, end of period			1,210			189			9			1,408			1,217			178			10			1,405

Change in plan assets
Fair value of plan assets, beginning of period			1,164			210			—			1,374			1,211			239			—			1,450
Actual return (loss) on plan assets			66			8			—			74			30			(16)			—			14
Currency exchange rate gain (loss)			—			16			—			16			—			(3)			—			(3)
Employer contributions			7			—			1			8			—			—			2			2
Benefits paid			(78)			(11)			(1)			(90)			(77)			(10)			(2)			(89)
Settlements			(1)			—			—			(1)			—			—			—			—
Fair value of plan assets, end of period			1,158			223			—			1,381			1,164			210			—			1,374

Funded status asset (liability), end of period		$	(52)		$	34		$	(9)		$	(27)		$	(53)		$	32		$	(10)		$	(31)

The balance sheet classifications and accumulated benefit obligations were as follows (in millions):


	December 31, 2025								December 31, 2024
		U.S.		U.K.		OPEB				U.S.		U.K.		OPEB
		Plans		Plan		Plans		Total		Plans		Plan		Plans		Total
Balance sheet classification, end of period:
Pension asset, non-current	$	44	$	34	$	—	$	78	$	41	$	32	$	—	$	73
Pension liability, current		—		—		(2)		(2)		(1)		—		(3)		(4)
Pension liability, non-current		(96)		—		(7)		(103)		(93)		—		(7)		(100)
Accumulated other comprehensive loss (income), before taxes		112		84		—		196		102		88		(1)		189

Accumulated benefit obligation, end of period	$	1,210	$	189	$	9	$	1,408	$	1,217	$	178	$	10	$	1,405

Because our defined benefit plans no longer accrue benefits for participants, the projected benefit obligation is equivalent to the accumulated benefit obligation. Certain amounts related to plans with a projected benefit obligation and accumulated benefit obligation in excess of plan assets were as follows (in millions):


		December 31, 2025												December 31, 2024
		U.S.			U.K.			OPEB						U.S.			U.K.			OPEB
		Plans			Plan			Plans			Total			Plans			Plan			Plans			Total
Projected benefit obligation / accumulated benefit obligation		$	101		$	—		$	9		$	110		$	100		$	—		$	10		$	110
Fair value of plan assets			5			—			—			5			6			—			—			6

The amounts in accumulated other comprehensive loss (income) that have not been recognized were as follows (in millions):


		December 31, 2025												December 31, 2024
		U.S.			U.K.			OPEB						U.S.			U.K.			OPEB
		Plans			Plan			Plans			Total			Plans			Plan			Plans			Total
Actuarial (gain) loss, net		$	112		$	83		$	—		$	195		$	102		$	87		$	2		$	191
Prior service cost (credit), net			—			1			—			1			—			1			(3)			(2)
Accumulated other comprehensive loss (income), before taxes		$	112		$	84		$	—		$	196		$	102		$	88		$	(1)		$	189

Plan assets—The weighted-average target and actual allocations of assets for the funded defined benefit plans were as follows:


		December 31, 2025								December 31, 2024
		Target allocation				Actual allocation				Target allocation				Actual allocation
		U.S.		U.K.		U.S.		U.K.		U.S.		U.K.		U.S.		U.K.
		Plans		Plan		Plans		Plan		Plans		Plan		Plans		Plan
Equity securities		—	%	—	%	—	%	—	%	—	%	20	%	—	%	26	%
Fixed income securities		—	%	95	%	—	%	90	%	99	%	73	%	99	%	65	%
Other investments		100	%	5	%	100	%	10	%	1	%	7	%	1	%	9	%
Total		100	%	100	%	100	%	100	%	100	%	100	%	100	%	100	%

We periodically review our investment policies, plan assets and asset allocation strategies in conjunction with asset performance relative to specified objectives. In August 2025, using trust assets for the largest of our U.S. Plans, we purchased an insurance buy-in contract as a plan asset with an initial value of $1.107 billion. Under the buy-in contract, the insurer reimburses the plan as it continues to satisfy benefit obligations for which it remains responsible, resulting in no net cash flows in the plan. For the U.K. Plan, the plan trustees establish asset allocation strategies consistent with requirements of the United Kingdom pension regulators with guidance from financial advisors and company representatives.

Investment managers for the U.K. Plan are given established ranges within which the investments may deviate from the target allocations. The plan investment managers have discretion to select securities within each asset category. Given this discretion, the plan may occasionally hold positions in our debt or equity securities. Any such positions are expected to be immaterial relative to asset categories and total plan assets.

The investments for our funded defined benefit plans were categorized as follows (in millions):


		December 31, 2025
		U.S. Plans									U.K. Plan									Total
		Level 1			Level 2			Level 3			Level 1			Level 2			Level 3			Level 1			Level 2			Level 3
Mutual funds
Non-U.S. equity funds		$	—		$	—		$	—		$	—		$	5		$	—		$	—		$	5		$	—
Bond funds			—			—			—			—			201			—			—			201			—
Total mutual funds			—			—			—			—			206			—			—			206			—

Other investments
Cash and money market funds			55			—			—			6			—			—			61			—			—
Buy-in contract			—			—			1,103			—			—			—			—			—			1,103
Synthetic leveraged credit fund			—			—			—			—			11			—			—			11			—
Total other investments			55			—			1,103			6			11			—			61			11			1,103

Total investments		$	55		$	—		$	1,103		$	6		$	217		$	—		$	61		$	217		$	1,103


		December 31, 2024
		U.S. Plans									U.K. Plan									Total
		Level 1			Level 2			Level 3			Level 1			Level 2			Level 3			Level 1			Level 2			Level 3
Mutual funds
Non-U.S. equity funds		$	4		$	—		$	—		$	—		$	55		$	—		$	4		$	55		$	—
Bond funds			1,149			2			—			—			136			—			1,151			136			—
Total mutual funds			1,153			2			—			—			191			—			1,155			191			—

Other investments
Cash and money market funds			9			—			—			2			—			—			9			2			—
Synthetic leveraged credit fund			—			—			—			—			17			—			—			17			—
Total other investments			9			—			—			2			17			—			9			19			—

Total investments		$	1,162		$	2		$	—		$	2		$	208		$	—		$	1,164		$	210		$	—

We estimated the fair values of the plan assets by applying the market approach, as categorized above, using either (i) significant observable inputs, representative of Level 1 fair value measurements, including market prices of actively traded funds, (ii) significant other observable inputs, representative of Level 2 fair value measurements, including the market prices of underlying securities in trust funds, or (iii) significant unobservable inputs, representative of Level 3 fair value measurements, including the demographic inputs used to develop expected future cash flows, which were discounted at prevailing market discount rates, for the actuarial valuation of the buy-in contract.

Funding contributions and benefit payments—In the years ended December 31, 2025, 2024 and 2023, we made an aggregate contribution of $8 million, $2 million and $8 million, respectively, to the defined benefit pension plans and the OPEB Plans using our cash flows from operations. In the year ending December 31, 2026, we expect to make an aggregate contribution of $5 million, including $3 million and $2 million to the defined benefit pension plans and the OPEB Plans, respectively.

The projected benefits payments were as follows (in millions):


		U.S.			U.K.			OPEB
		Plans			Plan			Plans			Total
Years ending December 31,
2026		$	85		$	8		$	2		$	95
2027			85			8			2			95
2028			85			9			1			95
2029			86			10			1			97
2030			86			11			1			98
2031 - 2035			431			67			1			499

- Definition

The entire disclosure for retirement benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (o)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (p)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (q)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 60
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480266/715-60-50-3

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480126/715-20-S99-2

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 70
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480794/715-70-50-1

Reference 7: http://www.xbrl.org/2003/role/exampleRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480482/715-20-55-17

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)(iv)(03)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (l)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/715/tableOfContent

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+ Details

Accounting Standards Updates

12 Months Ended

Dec. 31, 2025

Accounting Standards Updates

Accounting Standards Updates

Note 3—Accounting Standards Updates

Recently adopted accounting standards

Income taxes—Effective for the year ended December 31, 2025, we adopted the accounting standards update that requires significant incremental disclosures intended to enhance the transparency and decision-usefulness of income tax disclosures, particularly with regard to the effective tax rate reconciliation table and income taxes paid. We have provided new disclosures, as required, presented on a prospective basis in our notes to consolidated financial statements. See Note 10—Income Taxes.

Recently issued accounting standards updates not yet adopted

Disaggregated income statement expenses—Effective for the year ending December 31, 2027, we will adopt the accounting standards update that requires, in the notes to consolidated financial statements, disaggregated disclosures of certain categories of expenses that are included in expense line items on the face of the consolidated statements of operations. The disclosures will be required on an annual and interim basis. We will provide the new disclosures, as required, for annual periods beginning with our annual report on Form 10-K for the year ending December 31, 2027, and subsequently, for interim periods beginning with our quarterly report on Form 10-Q for the quarterly period ending March 31, 2028. We continue to evaluate the requirements. Although our adoption will require us to augment certain disclosures in the notes to consolidated financial statements, we do not expect such adoption to have a material effect on our consolidated statements of financial position, operations or cash flows.

- Definition

The entire disclosure for change in accounting principle. Includes, but is not limited to, nature, reason, and method of adopting amendment to accounting standards or other change in accounting principle.

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+ Details

Supplemental Balance Sheet Information

12 Months Ended

Dec. 31, 2025

Supplemental Balance Sheet Information

Supplemental Balance Sheet Information

Note 16—Supplemental Balance Sheet Information

Other current liabilities were comprised of the following (in millions):


		December 31,
		2025			2024
Other current liabilities
Accrued employee benefits and payroll-related liabilities		$	166		$	136
Accrued interest			101			134
Accrued taxes, other than income			28			39
Finance lease liability			51			47
Operating lease liabilities			8			7
Contract liabilities			181			231
Contingent liabilities			87			94
Other			5			3
Total other current liabilities		$	627		$	691

Other long-term liabilities were comprised of the following (in millions):


		December 31,
		2025			2024
Other long-term liabilities
Postemployment benefit plan obligations		$	103		$	100
Finance lease liability			169			224
Operating lease liabilities			86			88
Income taxes payable			90			65
Contract liabilities			92			212
Other			42			40
Total other long-term liabilities		$	582		$	729

Equity (Shares held) (Details) - shares shares in Millions	Dec. 31, 2025	Dec. 31, 2024
Class of Stock [Line Items]
Number of shares held for future use	82.9	22.5
Subsidiary
Class of Stock [Line Items]
Number of shares held for future use	19.6	42.5

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Long-Lived Assets (Disaggregation) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024
Operating segments
Long-lived assets	$ 13,003	$ 16,276
Property and equipment	$ 17,451	$ 22,417
Percentage of property and equipment represented by rigs and related equipment	98.00%	98.00%
Capitalized interest costs on construction work in progress	$ 15	$ 39
UNITED STATES
Operating segments
Long-lived assets	6,487	6,727
NORWAY
Operating segments
Long-lived assets	1,941	2,017
BRAZIL
Operating segments
Long-lived assets	1,914	1,993
GREECE
Operating segments
Long-lived assets	611	2,531
Other countries
Operating segments
Long-lived assets	2,050	3,008
Rigs and Related Equipment
Operating segments
Property and equipment	$ 17,100	$ 22,000

Loss Per Share (Tables)

12 Months Ended

Dec. 31, 2025

Loss Per Share

Schedule of basic and diluted loss per share

The computation of basic and diluted loss per share was as follows (in millions, except per share data):


	Years ended December 31,
	2025				2024				2023
	Basic		Diluted		Basic		Diluted		Basic		Diluted
Numerator for loss per share
Net loss attributable to controlling interest	$	(2,915)	$	(2,915)	$	(512)	$	(512)	$	(954)	$	(954)
Effect of convertible debt instruments, net of tax		—		—		—		(189)		—		—
Loss for per share calculation	$	(2,915)	$	(2,915)	$	(512)	$	(701)	$	(954)	$	(954)

Denominator for loss per share
Weighted-average shares outstanding		960		960		850		850		768		768
Effect of convertible debt instruments		—		—		—		75		—		—
Weighted-average shares for per share calculation		960		960		850		925		768		768


Loss per share	$	(3.04)	$	(3.04)	$	(0.60)	$	(0.76)	$	(1.24)	$	(1.24)

Schedule of antidilutive securities

We excluded from the computations certain shares issuable as follows because the effect would have been antidilutive (in millions):


	Years ended December 31,
	2025	2024	2023
Exchangeable bonds	102	45	151
Share-based awards	8	11	19
Warrants (a)	—	6	10

(a)

For the year ended December 31, 2025, the warrants were antidilutive since the exercise price was greater than the average price for our shares.

Leases (Aggregate Future Minimum Lease Payments) (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Operating lease maturity
2026	$ 15
2027	14
2028	14
2029	14
2030	13
Thereafter	64
Total future minimum rental payment	134
Less amount representing imputed interest	(40)
Present value of future minimum rental payments under operating leases	94
Current portion, recorded in other current liabilities	8	$ 7
Long-term lease liabilities, recorded in other long-term liabilities	86	88
Finance lease maturity
2026	65
2027	70
2028	71
2029	47
Total future minimum rental payment	253
Less amount representing imputed interest	(33)
Present value of future minimum rental payments under finance leases	220
Current portion, recorded in other current liabilities	51	47
Long-term lease liabilities, recorded in other long-term liabilities	$ 169	$ 224

CONSOLIDATED BALANCE SHEETS (Parenthetical)	Dec. 31, 2025 $ / shares shares	Dec. 31, 2024 $ / shares shares
CONSOLIDATED BALANCE SHEETS
Shares, Par value \| (per share)	$ 0.1	$ 0.1
Shares, authorized	1,204,009,681	1,057,879,029
Shares, conditionally authorized	141,262,093	141,262,093
Shares, issued	1,204,009,681	940,828,901
Shares, outstanding	1,101,528,481	875,830,772

Financial Instruments (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Financial instruments
Total debt	$ 5,657	$ 6,881
Carrying amount
Financial instruments
Cash and cash equivalents	620	560
Restricted cash and cash equivalents	377	381
Total debt	5,657	6,881
Fair value
Financial instruments
Cash and cash equivalents	620	560
Restricted cash and cash equivalents	377	381
Total debt	$ 5,755	$ 6,888

Significant Accounting Policies (Policies)	12 Months Ended
Significant Accounting Policies (Policies)	Dec. 31, 2025
Significant Accounting Policies
Accounting estimates	Accounting estimates—To prepare financial statements in accordance with accounting principles generally accepted in the United States (“U.S.”), we must make judgments by applying estimates and assumptions that affect the reported amounts of assets, liabilities, revenues and expenses and the disclosures of contingent assets and liabilities. On an ongoing basis, we evaluate our estimates and assumptions, including those related to our income taxes, property and equipment, equity investments, contingencies, allowance for excess materials and supplies, assets held for sale, postemployment benefit plans and share-based compensation. We base our estimates and assumptions on historical experience and other factors that we believe are reasonable. Actual results could differ from such estimates.
Fair value measurements	Fair value measurements—We estimate fair value at an exchange price that would be received to sell an asset or paid to transfer a liability in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants. Our valuation techniques require inputs that we categorize using a three-level hierarchy, from highest to lowest level of observable inputs, as follows: (1) significant observable inputs, including unadjusted quoted prices for identical assets or liabilities in active markets (“Level 1”), (2) significant other observable inputs, including direct or indirect market data for similar assets or liabilities in active markets or identical assets or liabilities in less active markets (“Level 2”) and (3) significant unobservable inputs, including those that require considerable judgment for which there is little or no market data (“Level 3”). When a valuation requires multiple input levels, we categorize the entire fair value measurement according to the lowest level of input that is significant to the measurement even though we may have also utilized significant inputs that are more readily observable.
Consolidation	Consolidation—We consolidate entities in which we have a majority voting interest and entities that meet the criteria for variable interest entities for which we are deemed to be the primary beneficiary for accounting purposes. We eliminate intercompany transactions and accounts in consolidation. We apply the equity method of accounting for an equity investment in an unconsolidated entity if we have the ability to exercise significant influence over the entity that (a) does not meet the variable interest entity criteria or (b) meets the variable interest entity criteria, but for which we are not deemed to be the primary beneficiary. We measure other equity investments at fair value if the investment has a fair value that is readily determinable; otherwise, we measure the investment at cost, less any impairment. We separately present within equity on our consolidated balance sheets the ownership interests attributable to parties with noncontrolling interests in our consolidated subsidiaries, and we separately present net income attributable to such parties on our consolidated statements of operations. See Note 4—Unconsolidated Affiliates and Note 13—Equity.
Functional currency	Functional currency—We consider the U.S. dollar to be the functional currency for all of our operations since the majority of our revenues and expenditures are denominated in U.S. dollars. Consequently, our exposure to currency exchange rate fluctuations is limited. We recognize currency exchange rate gains and losses in other, net. In the years ended December 31, 2025, 2024 and 2023, we recognized a net loss of $13 million, a net gain of $16 million and a net gain of $10 million, respectively, related to currency exchange rates.
Revenues and related pre-operating costs	Revenues and related pre-operating costs—We recognize revenues earned under our drilling contracts based on variable dayrates, which range from a full operating dayrate to lower rates or zero rates for periods when drilling operations are interrupted or restricted, based on the specific activities we perform during the contract on an hourly, or more frequent, basis. Such dayrate consideration is attributed to the distinct time period to which it relates within the contract term, and therefore, is recognized as we perform the services. When the operating dayrate declines over the contract term, we recognize revenues on a straight-line basis over the estimated contract period. We recognize reimbursement revenues and the corresponding costs as we provide the customer-requested goods and services, when such reimbursable costs are incurred while performing drilling operations. Prior to performing drilling operations, we may receive pre-operating revenues, on either a fixed lump-sum or variable dayrate basis, for mobilization, contract preparation, customer-requested goods and services or capital upgrades, for which we record a contract liability and recognize as revenues on a straight-line basis over the estimated contract period. We recognize losses for loss contracts as such losses are incurred. We recognize revenues for demobilization over the contract period unless otherwise constrained. We recognize revenues from contract terminations as we fulfill our obligations and all contingencies have been resolved. We apply the optional exemption that permits us to exclude disclosure of the estimated transaction price related to the variable portion of unsatisfied performance obligations at the end of the reporting period, as our transaction price is typically based on a single performance obligation consisting of a series of distinct hourly, or more frequent, periods, the variability of which will be resolved at the time of the future services. To obtain contracts with our customers, we incur pre-operating costs to prepare a rig for contract and mobilize a rig to the drilling location. We defer such pre-operating contract preparation and mobilization costs for recognition in operating and maintenance costs over the estimated contract period on a straight-line basis, consistent with the general pace of activity. See Note 5—Revenues.
Income taxes	Income taxes—We provide for income taxes based on expected taxable income, statutory rates and tax laws in the jurisdictions in which we operate or have a taxable presence. We recognize the effect of changes in tax laws as of the date of enactment. We recognize potential global intangible low-taxed income inclusions as a period cost. We establish liabilities for estimated tax exposures, and we recognize the provisions and benefits resulting from changes to those liabilities, together with related interest and penalties, in income tax expense or benefit. Income tax exposure items include potential challenges to permanent establishment positions, intercompany pricing, disposition transactions, and withholding tax rates and their applicability. Such tax exposures may be affected by changes in applicable tax law or other factors, which could cause us to revise our prior estimates, and are generally resolved through the settlement of audits within the tax jurisdictions or by judicial means. We measure deferred tax assets and liabilities using enacted tax rates that will apply in the years in which the deferred tax assets and liabilities are expected to be recovered or paid. To evaluate our ability to realize deferred tax assets, we consider all available positive and negative evidence, including projected future taxable income and the existence of cumulative losses in recent years. We record a valuation allowance for deferred tax assets when it is more likely than not that some or all of the benefit from the deferred tax asset will not be realized. For example, we may record a valuation allowance for deferred tax assets resulting from net operating losses incurred during the year in certain jurisdictions for which the benefit of the losses will not be realized or for foreign tax credit carryforwards that may expire prior to their utilization. See Note 10—Income Taxes.
Cash and cash equivalents	Cash and cash equivalents—We consider cash equivalents to include highly liquid debt instruments with original maturities of three months or less, such as time deposits with commercial banks that have high credit ratings, U.S. Treasury and government securities, Eurodollar time deposits, certificates of deposit and commercial paper. We may also invest excess funds in no-load, open-ended, management investment trusts. Such management trusts invest exclusively in high-quality money market instruments.
Restricted cash and cash equivalents	Restricted cash and cash equivalents—We maintain restricted cash and cash equivalents that are either pledged for debt service under certain bond indentures, as required under certain bank credit arrangements, or held in accounts that are subject to restrictions due to legislation, regulation or court order. We classify such restricted cash and cash equivalents in current assets if the restriction is expected to expire or otherwise be resolved within one year or if such funds are considered to correspond to liabilities that are properly classified as current liabilities. See Note 8—Debt.
Materials and supplies	Materials and supplies—We record materials and supplies at their average cost less an allowance for excess items. We estimate the allowance for excess items based on historical experience and expectations for future use of the materials and supplies. At December 31, 2025 and 2024, our allowance for excess items was $140 million and $178 million, respectively. The decrease was primarily due to the disposal of materials and supplies associated with rigs and related assets sold or classified as held for sale.
Assets held for sale	Assets held for sale—We classify an asset as held for sale when the facts and circumstances meet the criteria for such classification, including the following: (a) we have committed to a plan to sell the asset, (b) the asset is available for immediate sale, (c) we have initiated actions to complete the sale, including locating a buyer, (d) the sale is expected to be completed within one year, (e) the asset is being actively marketed at a price that is reasonable relative to its fair value, and (f) the plan to sell is unlikely to be subject to significant changes or termination. The carrying amount of our assets held for sale is measured at the lower of its carrying amount or fair value less cost to sell. We consider a held-for-sale asset to be impaired to the extent its carrying amount exceeds its estimated fair value less cost to sell. See Note 6—Long-Lived Assets.
Property and equipment	Property and equipment—We apply judgment to account for our property and equipment, consisting primarily of offshore drilling rigs and related equipment, related to estimates and assumptions for cost capitalization, useful lives and salvage values. We base our estimates and assumptions on historical experience and expectations regarding future industry conditions and operations. At December 31, 2025, the aggregate carrying amount of our property and equipment represented 80 percent of our total assets. We capitalize expenditures for newbuilds, renewals, replacements and improvements, including capitalized interest, if applicable, and we recognize the expense for maintenance and repair costs as incurred. For newbuild construction projects, we also capitalize the initial preparation, mobilization and commissioning costs incurred until the drilling unit is placed into service. Upon sale or other disposition of an asset, we recognize a net gain or loss on disposal of the asset, which is measured as the difference between the net carrying amount of the asset and the net proceeds received. We compute depreciation using the straight-line method after allowing for salvage values. The estimated original useful life of our drilling units is 35 years, our buildings and improvements range from three to 30 years and our machinery and equipment range from four to 20 years. We reevaluate the remaining useful lives and salvage values of our rigs when certain events occur that directly impact the useful lives and salvage values of the rigs, including changes in operating condition, functional capability and market and economic factors. When evaluating the remaining useful lives of rigs, we also consider major capital upgrades required to perform certain contracts and the long-term impact of those upgrades on future marketability.
Long-lived asset impairment	Long-lived asset impairment—We review the carrying amounts of long-lived assets, including property and equipment and right-of-use assets, for potential impairment when events occur or circumstances change that indicate that the carrying amount of such assets may not be recoverable. For assets classified as held and used, we determine recoverability by evaluating the estimated undiscounted future net cash flows based on projected dayrates and utilization of the asset group under review. We consider our asset groups to be ultra-deepwater floaters and harsh environment floaters. When an impairment of an asset group is indicated, we measure an impairment as the amount by which the carrying amount of the asset group exceeds its estimated fair value. We estimate the fair value of an asset group by applying a variety of valuation methods, incorporating a combination of income, market and cost approaches, using projected discounted cash flows and estimates of the exchange price that would be received for the assets in the principal or most advantageous market for the assets in an orderly transaction between market participants as of the measurement date. See Note 6—LongLived Assets.
Equity investments and impairment	Equity investments and impairment—We review our equity-method investments, and other equity investments for which a readily determinable fair value is not available, for potential impairment when events or changes in circumstances indicate that the carrying amount of the investment might not be recoverable in the near term. If we determine that an impairment that is other than temporary exists, we recognize an impairment loss, measured as the amount by which the carrying amount of the investment exceeds its estimated fair value. To estimate the fair value of the investment, we apply valuation methods that rely primarily on the income and market approaches. We amortize the basis difference caused by such impairments using the straight-line method over the estimated life of the asset. See Note 4—Unconsolidated Affiliates.
Pension and other postemployment benefit plans	Pension and other postemployment benefit plans—We use a measurement date of January 1 to determine net periodic benefit costs and December 31 to determine plan benefit obligations and the fair values of plan assets. We determine our net periodic benefit costs based on a market-related value of assets that reduces year-to-year volatility by including investment gains or losses subject to amortization over a five-year period from the year in which they occur. We calculate investment gains or losses for this purpose as the difference between the expected return calculated using the market-related value of assets and the actual return based on the market-related value of assets. If gains or losses exceed 10 percent of the greater of plan assets or plan liabilities, we amortize such gains or losses over the average expected future lifetime of the participants. We measure the actuarially determined obligations and related costs for our defined benefit pension and other postemployment benefit plans, retiree life insurance and medical benefits, by applying assumptions, the most significant of which include long-term rate of return on plan assets, discount rates and mortality rates. For the long-term rate of return, we develop our assumptions regarding the expected rate of return on plan assets based on projected long-term investment returns, and we weight the assumptions based on each plan’s asset allocation. For the discount rate, we base our assumptions on a yield curve approach using Aa-rated corporate bonds and the expected timing of future benefit payments. At December 31, 2025 and 2024, the funded status of our pension and other postemployment benefit plans represented an aggregate liability of $105 million and $104 million, respectively, and an aggregate asset of $78 million and $73 million, respectively. See Note 9—Benefit Plans.
Share-based compensation	Share-based compensation—To measure the fair values of granted or modified service-based restricted share units, we use the market price of our shares on the grant date or modification date. To measure the fair values of granted or modified performance-based restricted share units subject to market factors, we use an average price at the performance start date and project performance based on a Monte Carlo simulation model under a risk-neutral approach and apply assumptions for the expected life, risk-free interest rate, expected volatility and dividend yield. To measure the fair values of granted or modified performance-based restricted share units that are subject to performance targets, we use the market price of our shares on the grant date or modification date and adjust the value for the projected performance rate expected to be achieved at the end of the measurement period. We recognize share-based compensation expense in the same financial statement line item as cash compensation paid to the respective employees or non-employee directors. We recognize such compensation expense on a straight-line basis over the service period through the date the employee or non-employee director is no longer required to provide service to earn the award. See Note 14—ShareBased Compensation.
Contingencies	Contingencies—We assess our contingencies on an ongoing basis to evaluate the appropriateness of our liabilities and disclosures for such contingencies. We establish liabilities for estimated loss contingencies when we believe a loss is probable and the amount of the probable loss can be reasonably estimated. Once established, we adjust the carrying amount of a contingent liability upon the occurrence of a recognizable event when facts and circumstances change, altering our previous assumptions with respect to the likelihood or amount of loss. We recognize corresponding assets for those loss contingencies that we believe are probable of being recovered through insurance. We recognize expense for legal costs as they are incurred, and we recognize a corresponding asset for such legal costs only if we expect such legal costs to be recovered through insurance.
Accounting standards updates	Recently adopted accounting standards Income taxes—Effective for the year ended December 31, 2025, we adopted the accounting standards update that requires significant incremental disclosures intended to enhance the transparency and decision-usefulness of income tax disclosures, particularly with regard to the effective tax rate reconciliation table and income taxes paid. We have provided new disclosures, as required, presented on a prospective basis in our notes to consolidated financial statements. See Note 10—Income Taxes. Recently issued accounting standards updates not yet adopted Disaggregated income statement expenses—Effective for the year ending December 31, 2027, we will adopt the accounting standards update that requires, in the notes to consolidated financial statements, disaggregated disclosures of certain categories of expenses that are included in expense line items on the face of the consolidated statements of operations. The disclosures will be required on an annual and interim basis. We will provide the new disclosures, as required, for annual periods beginning with our annual report on Form 10-K for the year ending December 31, 2027, and subsequently, for interim periods beginning with our quarterly report on Form 10-Q for the quarterly period ending March 31, 2028. We continue to evaluate the requirements. Although our adoption will require us to augment certain disclosures in the notes to consolidated financial statements, we do not expect such adoption to have a material effect on our consolidated statements of financial position, operations or cash flows.

Commitments and Contingencies (Tables)

12 Months Ended

Dec. 31, 2025

Commitments and Contingencies.

Schedule of aggregate future payments required under purchase obligations

At December 31, 2025, the aggregate future payments required under our service agreement obligations were as follows (in millions):


		Service
		agreement
		obligations
Years ending December 31,
2026		$	140
2027			117
2028			73
2029			51
2030			31
Thereafter			66
Total		$	478

Supplemental Segment Information (Details)	12 Months Ended
Supplemental Segment Information (Details)	Dec. 31, 2025 segment
Supplemental Segment information
Number of operating segments	1

Income Taxes (Unrecognized tax benefits) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Reconciliation of unrecognized tax benefits, excluding interest and penalties
Balance, beginning of period	$ 407	$ 449	$ 444
Additions for current year tax positions	49	13	45
Additions for prior year tax positions	39	11	5
Reductions due to settlements	(203)	(30)	(5)
Reductions related to statute of limitation expirations and changes in law	(8)	(19)	(14)
Reductions for prior year tax positions		(17)	(26)
Balance, end of period	284	407	449
Unrecognized tax benefits
Unrecognized tax benefits, excluding interest and penalties	284	407	449
Interest and penalties	18	7
Unrecognized tax benefits, including interest and penalties	302	414
Interest and penalties related to unrecognized tax benefits recognized as a component of income tax expense	11	$ (2)	$ 18
Unrecognized benefits netted against NOL deferred tax assets	235
Amount if recognized that would impact tax rate	$ 67

Unconsolidated Affiliates (Equity Investments) (Details) - USD ($) shares in Millions, $ in Millions	1 Months Ended		12 Months Ended
	Jun. 30, 2024	Feb. 28, 2023	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Investments
Proceeds from disposal of equity investment in unconsolidated affiliate			$ 6
Equity investment income (loss)			1	$ 4	$ (14)
Equity method investments			$ 121	123
Loss on impairment of investment in unconsolidated affiliate				5	5
Aggregate loss on impairment of assets held for sale, tax effect				$ 0	0
Payment to acquire interest					10
8.00% Senior Notes due February 2027
Investments
Debt instrument interest rate stated percentage	8.00%		8.00%	8.00%
Global Sea Mineral Resources
Investments
Equity ownership (as a percent)			16.00%
Equity method investment payment		$ 10
Equity investment non-cash contribution		$ 85
Orion/Transocean Norge
Investments
Equity method investments					$ 86
Equity ownership (as a percent)					33.00%
Ocean Minerals
Investments
Equity ownership (as a percent)			19.00%
Orion/Transocean Norge
Investments
Asset acquisition, consideration transferred	$ 431
Newly issued shares in asset acquisition (in shares)	55.5
Orion/Transocean Norge \| 8.00% Senior Notes due February 2027
Investments
Debt instrument face value	$ 130
Debt instrument interest rate stated percentage	8.00%
Orion/Transocean Norge \| Orion/Transocean Norge
Investments
Equity ownership (as a percent)	67.00%

Benefit Plans (Defined Benefit Pension and Other Postemployment Benefit Plans Net Periodic Benefit Costs) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2025 USD ($) plan	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Net periodic benefit costs, before tax
Interest cost	$ 77	$ 72	$ 74
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Interest Cost, Statement of Income or Comprehensive Income [Extensible Enumeration]	Other Nonoperating Income (Expense)	Other Nonoperating Income (Expense)	Other Nonoperating Income (Expense)
Expected return on plan assets	$ (80)	$ (97)	$ (95)
Defined Benefit Plan, Net Periodic Benefit (Cost) Credit, Expected Return (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Other Nonoperating Income (Expense)	Other Nonoperating Income (Expense)	Other Nonoperating Income (Expense)
Special termination benefits		$ 2
Settlements and curtailments		$ (2)
Defined Benefit Plan, Net Periodic Benefit (Cost) Credit, Settlement and Curtailment Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]		Other Nonoperating Income (Expense)
Actuarial loss, net	$ 3	$ 3	$ 2
Defined Benefit Plan, Net Periodic Benefit (Cost) Credit, Amortization of Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Other Nonoperating Income (Expense)	Other Nonoperating Income (Expense)	Other Nonoperating Income (Expense)
Prior service gain, net	$ (1)	$ (1)	$ (2)
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Amortization of Prior Service Cost (Credit), Statement of Income or Comprehensive Income [Extensible Enumeration]	Other Nonoperating Income (Expense)	Other Nonoperating Income (Expense)	Other Nonoperating Income (Expense)
Net periodic benefit costs (income)	$ (1)	$ (23)	$ (21)
UNITED STATES
Weighted-average assumptions
Discount rate (as a percent)	5.58%	4.88%	5.06%
Expected rate of return (as a percent)	5.66%	6.51%	6.41%
UNITED STATES \| Funded Plan
Net periodic benefit costs, before tax
Number Of Benefit Plans \| plan	3
UNITED STATES \| Unfunded Plan
Net periodic benefit costs, before tax
Number Of Benefit Plans \| plan	3
UNITED KINGDOM
Weighted-average assumptions
Discount rate (as a percent)	5.60%	4.50%	4.80%
Expected rate of return (as a percent)	4.80%	5.10%	5.00%
UNITED KINGDOM \| Funded Plan
Net periodic benefit costs, before tax
Number Of Benefit Plans \| plan	1
Transocean Plans \| UNITED STATES
Net periodic benefit costs, before tax
Interest cost	$ 67	$ 63	$ 65
Expected return on plan assets	(71)	(86)	(84)
Actuarial loss, net		1
Net periodic benefit costs (income)	(4)	(22)	(19)
Transocean Plans \| UNITED KINGDOM
Net periodic benefit costs, before tax
Interest cost	10	9	9
Expected return on plan assets	(9)	(11)	(11)
Actuarial loss, net	3	$ 2	$ 2
Net periodic benefit costs (income)	$ 4
OPEB Plans
Weighted-average assumptions
Discount rate (as a percent)	5.02%	4.80%	4.92%
Net periodic benefit costs, before tax
Special termination benefits		$ 2
Settlements and curtailments		(2)
Prior service gain, net	$ (1)	(1)	$ (2)
Net periodic benefit costs (income)	$ (1)	$ (1)	$ (2)

Business

12 Months Ended

Dec. 31, 2025

Business

Business

Note 1—Business

Overview

Transocean Ltd. (together with its subsidiaries and predecessors, unless the context requires otherwise, “Transocean,” “we,” “us” or “our”) is a leading international provider of offshore contract drilling services for oil and gas wells. As of December 31, 2025, we owned or had partial ownership interests in and operated a fleet of 27 mobile offshore drilling units, consisting of 20 ultra-deepwater drillships and seven harsh environment semisubmersibles.

We provide, as our primary business, contract drilling services in a single operating segment, which involves contracting our mobile offshore drilling rigs, related equipment and work crews to drill oil and gas wells. We specialize in technically demanding regions of the global offshore drilling business with a particular focus on ultra-deepwater and harsh environment drilling services. Our drilling fleet is one of the most versatile fleets in the world, consisting of drillships and semisubmersible floaters used in support of offshore drilling activities and offshore support services on a worldwide basis.

We perform contract drilling services by deploying our high-specification fleet in a single, global market that is geographically dispersed in oil and gas exploration and development areas throughout the world. The location of our rigs and the allocation of our resources to build or upgrade rigs are determined by the activities and needs of our customers. See Note 15—Supplemental Segment Information.

Agreement to acquire Valaris Limited

On February 9, 2026, we and Valaris Limited, an exempted company limited by shares incorporated under the laws of Bermuda ("Valaris"), entered into a Business Combination Agreement (the "Agreement") providing for the combination of Transocean and Valaris (the "Business Combination"). Pursuant to the Agreement, and on the terms and subject to the conditions thereof, we will acquire all of the issued and outstanding common shares, par value $0.01 each, of Valaris (the “Valaris Shares”) in exchange for Transocean Ltd. shares, par value $0.10 each, at an exchange ratio of 15.235 Transocean Ltd. shares for each Valaris Share. Pursuant to the Agreement, and on the terms and subject to the conditions thereof, at the time on which the order of the Supreme Court of Bermuda providing for its sanction of the Scheme of Arrangement is filed with the Registrar of Companies of Bermuda, the Business Combination will become effective and Valaris will become our wholly owned subsidiary. The board of directors of Transocean and Valaris each unanimously approved and declared advisable the Agreement and the transactions contemplated thereby, including the Business Combination.

Revenues (Pre-Opening Costs) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Revenues.
Recognized pre-operating costs	$ 158	$ 138	$ 69
Unrecognized pre-operating costs	$ 136	$ 224

Loss Per Share

12 Months Ended

Dec. 31, 2025

Loss Per Share

Loss Per Share

Note 11—Loss Per Share

The computation of basic and diluted loss per share was as follows (in millions, except per share data):


	Years ended December 31,
	2025				2024				2023
	Basic		Diluted		Basic		Diluted		Basic		Diluted
Numerator for loss per share
Net loss attributable to controlling interest	$	(2,915)	$	(2,915)	$	(512)	$	(512)	$	(954)	$	(954)
Effect of convertible debt instruments, net of tax		—		—		—		(189)		—		—
Loss for per share calculation	$	(2,915)	$	(2,915)	$	(512)	$	(701)	$	(954)	$	(954)

Denominator for loss per share
Weighted-average shares outstanding		960		960		850		850		768		768
Effect of convertible debt instruments		—		—		—		75		—		—
Weighted-average shares for per share calculation		960		960		850		925		768		768


Loss per share	$	(3.04)	$	(3.04)	$	(0.60)	$	(0.76)	$	(1.24)	$	(1.24)

We excluded from the computations certain shares issuable as follows because the effect would have been antidilutive (in millions):


	Years ended December 31,
	2025	2024	2023
Exchangeable bonds	102	45	151
Share-based awards	8	11	19
Warrants (a)	—	6	10

(a)

For the year ended December 31, 2025, the warrants were antidilutive since the exercise price was greater than the average price for our shares.

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Assets
Cash and cash equivalents	$ 620	$ 560
Accounts receivable, net	540	564
Materials and supplies, net	378	439
Assets held for sale	24	343
Restricted cash and cash equivalents	377	381
Other current assets	142	165
Total current assets	2,081	2,452
Property and equipment	17,451	22,417
Less accumulated depreciation	(4,874)	(6,586)
Property and equipment, net	12,577	15,831
Deferred tax assets, net	61	45
Other assets	923	1,043
Total assets	15,642	19,371
Liabilities and equity
Accounts payable	242	255
Accrued income taxes	22	31
Debt due within one year	445	686
Other current liabilities	627	691
Total current liabilities	1,336	1,663
Long-term debt	5,212	6,195
Deferred tax liabilities, net	404	499
Other long-term liabilities	582	729
Total long-term liabilities	6,198	7,423
Commitments and contingencies
Shares, $0.10 par value, 1,204,009,681 authorized, 141,262,093 conditionally authorized, 1,204,009,681 issued and 1,101,528,481 outstanding at December 31, 2025, and 1,057,879,029 authorized, 141,262,093 conditionally authorized, 940,828,901 issued and 875,830,772 outstanding at December 31, 2024	110	87
Additional paid-in capital	15,604	14,880
Accumulated deficit	(7,460)	(4,545)
Accumulated other comprehensive loss	(146)	(138)
Total controlling interest shareholders' equity	8,108	10,284
Noncontrolling interest		1
Total equity	8,108	10,285
Total liabilities and equity	$ 15,642	$ 19,371

Leases (Tables)

12 Months Ended

Dec. 31, 2025

Leases

Schedule of lease costs

The components of our lease costs were as follows (in millions):


	Years ended December 31,
Lease costs	2025		2024		2023
Short-term lease costs	$	15	$	10	$	4
Operating lease costs		10		16		14
Finance lease costs, amortization of right-of-use asset		20		20		20
Finance lease costs, interest on lease liability		20		24		27
Total lease costs	$	65	$	70	$	65

Schedule of lease cash flow information

Supplemental cash flow information for our leases was as follows (in millions):


	Years ended December 31,
	2025		2024		2023
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$	14	$	20	$	17
Operating cash flows from finance lease		6		4		—
Financing cash flows from finance lease		12		7		—

Schedule of future minimum payments on operating leases

At December 31, 2025, the aggregate future minimum lease payments were as follows (in millions):


	Operating		Finance
	leases		lease
Years ending December 31,
2026	$	15	$	65
2027		14		70
2028		14		71
2029		14		47
2030		13		—
Thereafter		64		—
Total future minimum rental payment		134		253
Less amount representing imputed interest		(40)		(33)
Present value of future minimum rental payments		94		220
Current portion, recorded in other current liabilities		8		51
Long-term lease liabilities, recorded in other long-term liabilities	$	86	$	169

Schedule of future minimum payments on finance leases

At December 31, 2025, the aggregate future minimum lease payments were as follows (in millions):


	Operating		Finance
	leases		lease
Years ending December 31,
2026	$	15	$	65
2027		14		70
2028		14		71
2029		14		47
2030		13		—
Thereafter		64		—
Total future minimum rental payment		134		253
Less amount representing imputed interest		(40)		(33)
Present value of future minimum rental payments		94		220
Current portion, recorded in other current liabilities		8		51
Long-term lease liabilities, recorded in other long-term liabilities	$	86	$	169

Leases

12 Months Ended

Dec. 31, 2025

Leases

Leases

Note 7—Leases

Overview—Our operating leases are principally for office space, storage facilities, land and operating equipment. At December 31, 2025, our operating leases had a weighted-average discount rate of 7.3 percent and a weighted-average remaining lease term of 9.9 years.

Our finance lease for the ultra-deepwater drillship Petrobras 10000 has an implicit interest rate of 7.8 percent and requires scheduled monthly installments through the lease expiration in August 2029, after which we are obligated to acquire the drillship from the lessor for one dollar. We recognize expense for the amortization of the right-of-use asset in depreciation and amortization. See Note 16—Supplemental Balance Sheet Information.

Lease costs—The components of our lease costs were as follows (in millions):


	Years ended December 31,
Lease costs	2025		2024		2023
Short-term lease costs	$	15	$	10	$	4
Operating lease costs		10		16		14
Finance lease costs, amortization of right-of-use asset		20		20		20
Finance lease costs, interest on lease liability		20		24		27
Total lease costs	$	65	$	70	$	65

Lease payments—Supplemental cash flow information for our leases was as follows (in millions):


	Years ended December 31,
	2025		2024		2023
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$	14	$	20	$	17
Operating cash flows from finance lease		6		4		—
Financing cash flows from finance lease		12		7		—

At December 31, 2025, the aggregate future minimum lease payments were as follows (in millions):


	Operating		Finance
	leases		lease
Years ending December 31,
2026	$	15	$	65
2027		14		70
2028		14		71
2029		14		47
2030		13		—
Thereafter		64		—
Total future minimum rental payment		134		253
Less amount representing imputed interest		(40)		(33)
Present value of future minimum rental payments		94		220
Current portion, recorded in other current liabilities		8		51
Long-term lease liabilities, recorded in other long-term liabilities	$	86	$	169

Income Taxes

12 Months Ended

Dec. 31, 2025

Income Taxes

Income Taxes

Note 10—Income Taxes

Overview—Transocean Ltd., a holding company and Swiss resident, is subject to Swiss federal, cantonal and communal income tax. For Swiss income taxes, however, qualifying net dividend income and net capital gains on the sale of qualifying investments in subsidiaries are exempt from taxation. Consequently, there is not a direct relationship between our Swiss earnings before income taxes and our Swiss income tax expense. In the year ended December 31, 2025, the amount of our loss before income tax benefit derived in Switzerland and non-Swiss jurisdictions was $2.01 billion and $937 million, respectively.

Tax provision and rate—The relationship between our provision for or benefit from income taxes and our income or loss before income taxes can vary significantly from period to period considering, among other factors, (a) the overall level of income before income taxes, (b) changes in the blend of income that is taxed based on gross revenues rather than income before taxes, (c) rig movements between taxing jurisdictions and (d) our rig operating structures. In the year ended December 31, 2025, the amount of our income tax provision (benefit) derived in Switzerland, Switzerland cantons, and non-Switzerland jurisdictions was $(21) million, $(13) million and $1 million, respectively. In the years ended December 31, 2025, 2024 and 2023, our effective tax rate was 1.1 percent, 2.2 percent and (1.4) percent, respectively, based on loss before income tax expense (benefit).

The components of our income tax provision (benefit) were as follows (in millions):


		Years ended December 31,
		2025			2024			2023
Current tax expense (benefit)		$	78		$	31		$	(5)
Deferred tax expense (benefit)			(111)			(42)			18
Income tax expense (benefit)		$	(33)		$	(11)		$	13

The following is a reconciliation of the income tax benefit computed at the Swiss holding company federal effective rate and our reported income tax benefit for the year ended December 31, 2025 (in millions, except percentages):


	Year ended
	December 31, 2025
Switzerland, federal statutory tax rate	$	(220)	7.48%
Switzerland, cantonal taxes		(13)	0.44%
Switzerland, changes in valuation allowance		131	(4.46)%

Non-Switzerland tax effects
Bermuda, changes in valuation allowance		212	(7.21)%
Bermuda, tax rate differential		(107)	3.64%
Bermuda, other, net		13	(0.42)%
United States, tax rate differential		65	(2.21)%
United States, changes in valuation allowance		20	(0.68)%
United States, other, net		(15)	0.51%
Luxembourg, changes due to operational restructuring		43	(1.46)%
Luxembourg, changes in valuation allowance		(20)	0.68%
Luxembourg, other, net		8	(0.27)%
Norway, changes in currency exchange		(17)	0.56%
Norway, other, net		24	(0.82)%
Hungary, changes in valuation allowance		26	(0.88)%
Hungary, changes in currency exchange		(25)	0.85%
Hungary, other, net		1	(0.02)%
Brazil, tax rate differential		16	(0.54)%
Brazil, other, net		(19)	0.65%
United Kingdom, changes in valuation allowance		(36)	1.22%
United Kingdom, other, net		(5)	0.15%
Other, net		9	(0.30)%

Changes in unrecognized tax benefits		(123)	4.18%

Other adjustments
Switzerland, changes due to operational restructuring		(13)	0.44%
Switzerland, other, net		12	(0.40)%
Effective tax rate	$	(33)	1.13%

In the year ended December 31, 2025, we recognized a net tax benefit of $33 million, primarily resulting from a release of an uncertain tax position. For state and local income taxes, cantonal taxes in Zug, Switzerland made up the majority, greater than 50 percent, of the tax effect in this category.

The following is a reconciliation of the income tax benefit computed at the Swiss holding company federal effective rate of 7.83% and our reported consolidated income tax expense (benefit) for the years ended December 31, 2024 and 2023 (in millions):


			Years ended December 31,
			2024			2023
Income tax benefit at Swiss federal statutory rate			$	(40)		$	(74)
Earnings subject to rates different than the Swiss federal statutory rate				74			129
Changes in valuation allowance				208			(23)
Tax attribute expirations				185			—
Deemed profits taxes				12			11
Withholding taxes				4			5
Changes in unrecognized tax benefits, net				(4)			(37)
Changes due to organizational restructuring				(452)			—
Other, net				2			2
Income tax expense (benefit)			$	(11)		$	13

In the year ended December 31, 2024, as a result of operational and structural changes related to rig movements, we remeasured our deferred tax assets and liabilities related to Luxembourg, resulting in an increase of our net deferred tax asset from $8 million to $280 million, and such increase was substantially offset by an increase to our valuation allowance.

Unrecognized tax benefits—The changes to unrecognized tax benefits, excluding interest and penalties that we recognize as a component of income tax expense, were as follows (in millions):


		Years ended December 31,
			2025			2024			2023
Balance, beginning of period		$	407		$	449		$	444
Additions for current year tax positions			49			13			45
Additions for prior year tax positions			39			11			5
Reductions due to settlements			(203)			(30)			(5)
Reductions related to statute of limitation expirations and changes in law			(8)			(19)			(14)
Reductions for prior year tax positions			—			(17)			(26)
Balance, end of period		$	284		$	407		$	449

Our unrecognized tax benefits were as follows (in millions):


	December 31,
		2025			2024
Unrecognized tax benefits, excluding interest and penalties	$	284		$	407
Interest and penalties		18			7
Unrecognized tax benefits, including interest and penalties	$	302		$	414

In the years ended December 31, 2025, 2024 and 2023, we recognized, as a component of our income tax provision, expense of $11 million, benefit of $2 million and expense of $18 million, respectively, related to interest and penalties associated with our unrecognized tax benefits. As of December 31, 2025, we have unrecognized benefits of $302 million, including interest and penalties, against which we have recorded net operating loss deferred tax assets of $235 million, resulting in net unrecognized tax benefits of $67 million, including interest and penalties, that upon reversal would favorably impact our effective tax rate.

Tax positions and returns—We conduct operations through our various subsidiaries in countries throughout the world. Each country has its own tax regimes with varying nominal rates, deductions and tax attributes that are subject to changes resulting from new legislation, interpretation or guidance. From time to time, as a result of these changes, we may revise previously evaluated tax positions, which could cause us to adjust our recorded tax assets and liabilities. Tax authorities in certain jurisdictions are examining our tax returns and, in some cases, have issued assessments. We intend to defend our tax positions vigorously. Although we can provide no assurance as to the outcome of the aforementioned changes, examinations or assessments, we do not expect the ultimate liability to have a material adverse effect on our consolidated statement of financial position or results of operations; however, it could have a material adverse effect on our consolidated statement of cash flows.

Brazil tax investigations—In December 2005, the Brazilian tax authorities began issuing tax assessments with respect to our tax returns for the years 2000 through 2004. In May 2014, the Brazilian tax authorities issued an additional tax assessment for the years 2009 and 2010. We filed protests with the Brazilian tax authorities for the assessments and are engaged in the appeals process, and a portion of two cases were favorably closed. As of December 31, 2025, the remaining aggregate tax assessment, including interest and penalties, was for corporate income tax of BRL 523 million, equivalent to $95 million, and indirect tax of BRL 96 million, equivalent to $17 million. We believe our returns are materially correct as filed, and we are vigorously contesting these assessments. An unfavorable outcome on these proposed assessments could have a material adverse effect on our consolidated statement of financial position, results of operations or cash flows.

Tax payments—The components of our income taxes paid, net of refunds received, disaggregated by country, were as follows (in millions):


		Year ended
		December 31,
		2025
Switzerland, federal		$	2
Switzerland, cantonal			2
Total Switzerland			4

Brazil			17
United States			14
Angola			9
Australia			5
India			5
Hungary			4
Other countries (a)			3
Total tax payments, net of refunds received		$	61

(a)

The aggregate income taxes paid, net of refunds received, in other countries that individually represented less than 5 percent of total income taxes paid, net.

In the years ended December 31, 2024 and 2023, aggregate income taxes paid were $60 million and $41 million, respectively, before deducting refunds received.

Deferred taxes—The significant components of our deferred tax assets and liabilities were as follows (in millions):


		December 31,
		2025			2024
Deferred tax assets
Net operating loss carryforwards		$	1,985		$	1,541
Swiss historic depreciation and financing asset costs			1,034			1,053
Interest expense limitation			54			87
United Kingdom charter limitation			53			53
Accrued costs and expenses			33			20
Contract liabilities			6			22
Accrued payroll costs not currently deductible			11			12
Other			69			69
Valuation allowance			(2,479)			(2,089)
Total deferred tax assets, net of allowance			766			768

Deferred tax liabilities
Depreciation			(1,068)			(1,214)
Other			(41)			(8)
Total deferred tax liabilities			(1,109)			(1,222)

Deferred tax liabilities, net		$	(343)		$	(454)

We include taxes related to the earnings of all of our subsidiaries since we do not consider the earnings of any of our subsidiaries to be indefinitely reinvested.

At December 31, 2025 and 2024, our deferred tax assets included U.S. tax credits of $5 million, which will expire between 2042 and 2044. Deferred tax assets related to our net operating losses were generated in various worldwide tax jurisdictions. At December 31, 2025, our net deferred tax assets related to our net operating loss carryforwards included $1.57 billion, which do not expire, and $563 million, which will expire between 2026 and 2041.

As of December 31, 2025, our consolidated cumulative loss incurred over the recent three-year period represented significant objective negative evidence for the evaluation of the realizability of our deferred tax assets. Because such evidence has limited our ability to consider other subjective evidence, we evaluate each jurisdiction separately. We consider objective evidence, such as contract backlog activity, in jurisdictions in which we have profitable contracts, and the ability to carryback losses or utilize losses against potential exposures. If estimated future taxable income changes during the carryforward periods or if the cumulative loss is no longer present, we may adjust the amount of deferred tax assets that we expect to realize. At December 31, 2025 and 2024, due to uncertainty of realization, we had a valuation allowance of $2.48 billion and $2.09 billion, respectively, on net operating losses and other deferred tax assets due to the uncertainty of realization.

- Definition

The entire disclosure for income tax.

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+ Details

Insider Trading Policies and Procedures	12 Months Ended
Insider Trading Policies and Procedures	Dec. 31, 2025
Insider Trading Policies and Procedures [Line Items]
Insider Trading Policies and Procedures Adopted	true

Income Taxes (Income Taxes Paid, Net) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Income Taxes Paid
Switzerland, federal	$ 2
Switzerland, cantonal	2
Total Switzerland	4
Total tax payments, net of refunds received	61
Cash payments for income taxes		$ 60	$ 41
Brazil
Income Taxes Paid
Total tax payments, foreign	17
U.S.
Income Taxes Paid
Total tax payments, foreign	14
Angola
Income Taxes Paid
Total tax payments, foreign	9
Australia
Income Taxes Paid
Total tax payments, foreign	5
India
Income Taxes Paid
Total tax payments, foreign	5
Hungary
Income Taxes Paid
Total tax payments, foreign	4
Other countries
Income Taxes Paid
Total tax payments, foreign	$ 3

Financial Instruments

12 Months Ended

Dec. 31, 2025

Financial Instruments

Financial Instruments

Note 18—Financial Instruments

Overview—The carrying amounts and fair values of our financial instruments were as follows (in millions):


		December 31, 2025						December 31, 2024
		Carrying			Fair			Carrying			Fair
		amount			value			amount			value
Cash and cash equivalents		$	620		$	620		$	560		$	560
Restricted cash and cash equivalents			377			377			381			381
Total debt			5,657			5,755			6,881			6,888

Cash and cash equivalents—Our cash and cash equivalents are primarily invested in demand deposits, short-term time deposits and money market funds. The carrying amount of our cash and cash equivalents represents the historical cost, plus accrued interest, which approximates fair value because of the short maturities of the instruments.

Restricted cash and cash equivalents—Our restricted cash and cash equivalents, which are subject to restrictions due to collateral requirements, legislation, regulation or court order, are primarily invested in demand deposits and money market funds. The carrying amount of our restricted cash and cash equivalents represents the historical cost, plus accrued interest, which approximates fair value because of the short maturities of the instruments.

Total debt—The carrying amount of our total debt represents the principal amount, together with unamortized discounts, premiums and issue costs. The carrying amount and fair value of our total debt includes amounts related to our exchangeable bonds (see Note 8—

Debt). We estimated the fair value of our total debt using significant other observable inputs, representative of Level 2 fair value measurements, including the terms and credit spreads for the instruments and, with respect to our exchangeable bonds, the expected volatility of the market price for our shares.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

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+ Details

Equity (Warrants) (Details) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2025 USD ($) $ / shares shares	Dec. 31, 2024 USD ($) $ / shares shares	Jan. 01, 2024 $ / shares	Dec. 31, 2023 SFr / shares
Equity
Par value of common stock \| (per share)	$ 0.1	$ 0.1	$ 0.1	SFr 0.1
Number of warrants issued to subscribe \| shares	22.2	22.2
Exercise price \| $ / shares	$ 3.71	$ 3.71
Estimated fair value \| $	$ 16	$ 16

Revenues (Contract Intangible Assets and Contract Liabilities) (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Contract balances
Deferred contract revenues, recorded in other current liabilities	$ 181	$ 231
Deferred contract revenues, recorded in other long-term liabilities	92	212
Total contract liabilities	$ 273	$ 443	$ 398

Supplemental Cash Flow Information (Tables)

12 Months Ended

Dec. 31, 2025

Supplemental Cash Flow Information

Schedule of changes in other operating assets and liabilities

The reconciling adjustments of our net cash provided by operating activities that were attributable to the net change in other operating assets and liabilities were as follows (in millions):


		Years ended December 31,
		2025			2024			2023
Changes in other operating assets and liabilities
Increase in accounts receivable		$	(30)		$	(94)		$	(99)
(Increase) decrease in other assets			7			(92)			(91)
Increase (decrease) in accounts payable and other current liabilities			(12)			(86)			144
Decrease in other long-term liabilities			(7)			(3)			(6)
Change in income taxes receivable / payable, net			17			(19)			(36)
Change in receivables from / payables to affiliates, net			—			9			(8)
		$	(25)		$	(285)		$	(96)

Additional cash flow information

Additional cash flow information was as follows (in millions):


			Years ended December 31,
			2025			2024			2023
Certain cash operating activities
Cash payments for interest			$	538		$	521		$	408

Noncash investing and financing activities
Capital additions accrued at end of period	(a)		$	20		$	23		$	36
Acquisition of outstanding ownership interests in exchange for shares and debt	(b)			—			431			99
Debt investment exchanged for equity ownership interests	(c)			2			—			37
Finance lease installments settled with credits issued to customer	(d)			39			40			44
Shares issued in exchanges of exchangeable bonds	(e)			201			—			434

(a)	Additions to property and equipment for which we had accrued a corresponding liability in accounts payable at the end of the period. See Note 6—Long-Lived Assets.

(b)

In June 2024, we issued 55.5 million Transocean Ltd. shares and $130 million aggregate principal amount of 8.00% Senior Notes to acquire the outstanding ownership interest in Orion. In September 2023, we issued 11.9 million Transocean Ltd. shares to acquire the outstanding ownership interest in Liquila. See Note 4—Unconsolidated Affiliates, Note 6—Long-Lived Assets and Note 13—Equity.

(c)

In October 2025, we agreed to exchange borrowings due to us under a loan agreement with an unconsolidated affiliate for equity ownership interests. In September 2023, we agreed to exchange borrowings due to us under a financing arrangement with Orion for additional equity ownership interests in Orion. See Note 4—Unconsolidated Affiliates.

(d)	In the years ended December 31, 2025, 2024 and 2023, we agreed to settle installments due to the lessor under our finance lease by issuing corresponding credits to our customer for amounts due to us under the drilling contract. See Note 7—Leases.

(e)

In the year ended December 31, 2025, we issued 73.3 million Transocean Ltd. shares to certain holders that elected to exchange the 4.00% Exchangeable Bonds pursuant to the Exchange Agreements. In the year ended December 31, 2023, we issued 65.1 million Transocean Ltd. shares to certain holders that elected to exchange the 2.50% Exchangeable Bonds, the 4.00% Exchangeable Bonds and the 4.625% Exchangeable Bonds. See Note 8—Debt and Note 13—Equity.

Benefit Plans (Tables)

12 Months Ended

Dec. 31, 2025

Benefit Plans

Schedule of weighted-average assumptions

We estimated our net periodic benefit costs using the following weighted average assumptions:


		Year ended December 31, 2025						Year ended December 31, 2024						Year ended December 31, 2023
		U.S.		U.K.		OPEB		U.S.		U.K.		OPEB		U.S.		U.K.		OPEB
		Plans		Plan		Plans		Plans		Plan		Plans		Plans		Plan		Plans
Discount rate		5.58	%	5.60	%	5.02	%	4.88	%	4.50	%	4.80	%	5.06	%	4.80	%	4.92	%
Expected rate of return		5.66	%	4.80	%	na		6.51	%	5.10	%	na		6.41	%	5.00	%	na

“na” means not applicable.

We estimated our benefit obligations using the following weighted-average assumptions:

December 31, 2025

December 31, 2024

U.S.

U.K.

OPEB

U.S.

U.K.

OPEB

Plans

 

Plan

 

Plans

 

Plans

 

Plan

 

Plans

Discount rate

5.65

5.60

4.34

5.58

5.60

5.02

Schedule of net periodic benefit costs before tax

The components of net periodic benefit costs, recognized in other income and expense, were as follows (in millions):


	Year ended December 31, 2025								Year ended December 31, 2024								Year ended December 31, 2023
	U.S.		U.K.		OPEB				U.S.		U.K.		OPEB				U.S.		U.K.		OPEB
	Plans		Plan		Plans		Total		Plans		Plan		Plans		Total		Plans		Plan		Plans		Total
Net periodic benefit costs
Interest cost	$	67	$	10	$	—	$	77	$	63	$	9	$	—	$	72	$	65	$	9	$	—	$	74
Expected return on plan assets		(71)		(9)		—		(80)		(86)		(11)		—		(97)		(84)		(11)		—		(95)
Special termination benefits		—		—		—		—		—		—		2		2		—		—		—		—
Settlements and curtailments		—		—		—		—		—		—		(2)		(2)		—		—		—		—
Actuarial loss, net		—		3		—		3		1		2		—		3		—		2		—		2
Prior service gain, net		—		—		(1)		(1)		—		—		(1)		(1)		—		—		(2)		(2)
Net periodic benefit costs (income)	$	(4)	$	4	$	(1)	$	(1)	$	(22)	$	—	$	(1)	$	(23)	$	(19)	$	—	$	(2)	$	(21)

Schedule of changes in funded status

The changes in funded status were as follows (in millions):


		Year ended December 31, 2025												Year ended December 31, 2024
		U.S.			U.K.			OPEB						U.S.			U.K.			OPEB
		Plans			Plan			Plans			Total			Plans			Plan			Plans			Total
Change in projected benefit obligation
Projected benefit obligation, beginning of period		$	1,217		$	178		$	10		$	1,405		$	1,328		$	208		$	8		$	1,544
Actuarial (gain) loss, net			5			(2)			—			3			(97)			(27)			2			(122)
Interest cost			67			10			—			77			63			9			—			72
Currency exchange rate (gain) loss			—			14			—			14			—			(2)			—			(2)
Benefits paid			(78)			(11)			(1)			(90)			(77)			(10)			(2)			(89)
Settlements			(1)			—			—			(1)			—			—			—			—
Special termination benefits			—			—			—			—			—			—			2			2
Projected benefit obligation, end of period			1,210			189			9			1,408			1,217			178			10			1,405

Change in plan assets
Fair value of plan assets, beginning of period			1,164			210			—			1,374			1,211			239			—			1,450
Actual return (loss) on plan assets			66			8			—			74			30			(16)			—			14
Currency exchange rate gain (loss)			—			16			—			16			—			(3)			—			(3)
Employer contributions			7			—			1			8			—			—			2			2
Benefits paid			(78)			(11)			(1)			(90)			(77)			(10)			(2)			(89)
Settlements			(1)			—			—			(1)			—			—			—			—
Fair value of plan assets, end of period			1,158			223			—			1,381			1,164			210			—			1,374

Funded status asset (liability), end of period		$	(52)		$	34		$	(9)		$	(27)		$	(53)		$	32		$	(10)		$	(31)

Schedule of balance sheet classifications and accumulated benefit obligations

The balance sheet classifications and accumulated benefit obligations were as follows (in millions):


	December 31, 2025								December 31, 2024
		U.S.		U.K.		OPEB				U.S.		U.K.		OPEB
		Plans		Plan		Plans		Total		Plans		Plan		Plans		Total
Balance sheet classification, end of period:
Pension asset, non-current	$	44	$	34	$	—	$	78	$	41	$	32	$	—	$	73
Pension liability, current		—		—		(2)		(2)		(1)		—		(3)		(4)
Pension liability, non-current		(96)		—		(7)		(103)		(93)		—		(7)		(100)
Accumulated other comprehensive loss (income), before taxes		112		84		—		196		102		88		(1)		189

Accumulated benefit obligation, end of period	$	1,210	$	189	$	9	$	1,408	$	1,217	$	178	$	10	$	1,405

Schedule of projected benefit obligation in excess of plan assets

Certain amounts related to plans with a projected benefit obligation and accumulated benefit obligation in excess of plan assets were as follows (in millions):


		December 31, 2025												December 31, 2024
		U.S.			U.K.			OPEB						U.S.			U.K.			OPEB
		Plans			Plan			Plans			Total			Plans			Plan			Plans			Total
Projected benefit obligation / accumulated benefit obligation		$	101		$	—		$	9		$	110		$	100		$	—		$	10		$	110
Fair value of plan assets			5			—			—			5			6			—			—			6

Schedule of unrecognized accumulated other comprehensive loss (income)

The amounts in accumulated other comprehensive loss (income) that have not been recognized were as follows (in millions):


		December 31, 2025												December 31, 2024
		U.S.			U.K.			OPEB						U.S.			U.K.			OPEB
		Plans			Plan			Plans			Total			Plans			Plan			Plans			Total
Actuarial (gain) loss, net		$	112		$	83		$	—		$	195		$	102		$	87		$	2		$	191
Prior service cost (credit), net			—			1			—			1			—			1			(3)			(2)
Accumulated other comprehensive loss (income), before taxes		$	112		$	84		$	—		$	196		$	102		$	88		$	(1)		$	189

Schedule of allocations of plan assets

The weighted-average target and actual allocations of assets for the funded defined benefit plans were as follows:


		December 31, 2025								December 31, 2024
		Target allocation				Actual allocation				Target allocation				Actual allocation
		U.S.		U.K.		U.S.		U.K.		U.S.		U.K.		U.S.		U.K.
		Plans		Plan		Plans		Plan		Plans		Plan		Plans		Plan
Equity securities		—	%	—	%	—	%	—	%	—	%	20	%	—	%	26	%
Fixed income securities		—	%	95	%	—	%	90	%	99	%	73	%	99	%	65	%
Other investments		100	%	5	%	100	%	10	%	1	%	7	%	1	%	9	%
Total		100	%	100	%	100	%	100	%	100	%	100	%	100	%	100	%

Schedule of investments for the funded defined benefit plans

The investments for our funded defined benefit plans were categorized as follows (in millions):


		December 31, 2025
		U.S. Plans									U.K. Plan									Total
		Level 1			Level 2			Level 3			Level 1			Level 2			Level 3			Level 1			Level 2			Level 3
Mutual funds
Non-U.S. equity funds		$	—		$	—		$	—		$	—		$	5		$	—		$	—		$	5		$	—
Bond funds			—			—			—			—			201			—			—			201			—
Total mutual funds			—			—			—			—			206			—			—			206			—

Other investments
Cash and money market funds			55			—			—			6			—			—			61			—			—
Buy-in contract			—			—			1,103			—			—			—			—			—			1,103
Synthetic leveraged credit fund			—			—			—			—			11			—			—			11			—
Total other investments			55			—			1,103			6			11			—			61			11			1,103

Total investments		$	55		$	—		$	1,103		$	6		$	217		$	—		$	61		$	217		$	1,103


		December 31, 2024
		U.S. Plans									U.K. Plan									Total
		Level 1			Level 2			Level 3			Level 1			Level 2			Level 3			Level 1			Level 2			Level 3
Mutual funds
Non-U.S. equity funds		$	4		$	—		$	—		$	—		$	55		$	—		$	4		$	55		$	—
Bond funds			1,149			2			—			—			136			—			1,151			136			—
Total mutual funds			1,153			2			—			—			191			—			1,155			191			—

Other investments
Cash and money market funds			9			—			—			2			—			—			9			2			—
Synthetic leveraged credit fund			—			—			—			—			17			—			—			17			—
Total other investments			9			—			—			2			17			—			9			19			—

Total investments		$	1,162		$	2		$	—		$	2		$	208		$	—		$	1,164		$	210		$	—

Schedule of projected benefits payments

The projected benefits payments were as follows (in millions):


		U.S.			U.K.			OPEB
		Plans			Plan			Plans			Total
Years ending December 31,
2026		$	85		$	8		$	2		$	95
2027			85			8			2			95
2028			85			9			1			95
2029			86			10			1			97
2030			86			11			1			98
2031 - 2035			431			67			1			499

Risk Concentration (Details) $ in Millions	12 Months Ended
Risk Concentration (Details) $ in Millions	Dec. 31, 2025 USD ($) employee	Dec. 31, 2024 USD ($)	Dec. 31, 2023	Oct. 31, 2023
Labor Agreements
Allowance for credit losses \| $	$ 2	$ 2
Number of employees	5,600
Number of employees engaged through contract labor providers	380
4.625% Senior Guaranteed Exchangeable Bonds due September 2029
Labor Agreements
Debt instrument interest rate stated percentage	4.625%		4.625%	4.625%
Unionized Employees \| Workforce Subject to Collective Bargaining
Labor Agreements
Percentage of concentration	45.00%

- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References + Details

Revenues (Major Customers) (Details) - Revenue - Operating revenues	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Shell
Concentration Risk
Percentage of concentration	22.00%	27.00%	27.00%
Petrobras
Concentration Risk
Percentage of concentration	22.00%	21.00%	11.00%
Equinor
Concentration Risk
Percentage of concentration	12.00%	13.00%	16.00%
TotalEnergies
Concentration Risk
Percentage of concentration			12.00%

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 275
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482861/275-10-50-18

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 275
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482861/275-10-50-18

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 275
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 20
-Subparagraph (a)
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-URI https://asc.fasb.org/1943274/2147482861/275-10-50-20

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 275
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (d)
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-URI https://asc.fasb.org/1943274/2147482861/275-10-50-18

Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 275
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-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (c)
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-URI https://asc.fasb.org/1943274/2147482861/275-10-50-18

Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 275
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (b)
-Publisher FASB
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Reference 7: http://www.xbrl.org/2003/role/exampleRef
-Topic 275
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-Section 55
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 275
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-Name Accounting Standards Codification
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 954
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-Name Accounting Standards Codification
-Section 50
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478785/954-310-50-2

+ Details

- Definition

+ References + Details

Risk Concentration

12 Months Ended

Dec. 31, 2025

Risk Concentration

Risk Concentration

Note 19—Risk Concentration

Interest rate risk—We are exposed to interest rate risk related to our fixed-rate debt when we refinance maturing debt with new debt or when we early retire debt in open market repurchases or other market transactions. We are also exposed to interest rate risk related to our restricted and unrestricted cash equivalents, as the interest income earned on these investments is based on variable or short-term interest rates, which change with market interest rates.

Equity price risk—We are exposed to equity price risk primarily related to the bifurcated compound exchange feature contained within the indenture governing the 4.625% Exchangeable Bonds. The market price of our shares is the primary driver of the fair value of the exchange feature. An increase or decrease to the market price of our shares yields an increase or decrease to the carrying amount of the exchange feature, recorded as a component of our debt, and a corresponding change to interest expense.

Currency exchange rate risk—We are exposed to currency exchange rate risk primarily related to contract drilling revenues, employee compensation costs and purchasing costs that are denominated in currencies other than our functional currency, the U.S. dollar. To minimize the exposure to currency exchange rate risk, we use a variety of techniques, including structuring customer payment terms and occasionally entering into forward exchange contracts. We structure customer contracts, as our primary tool to manage currency exchange rate risk, to provide for payment in both U.S. dollars and local currency where the local currency portion is based on our anticipated local currency requirements over the contract term. Due to various factors, including customer acceptance, local banking laws, national content requirements, other statutory requirements, currency liquidity, local inflation and revenue efficiency, actual local currency needs may vary from those realized in the customer contracts, resulting in partial exposure to currency exchange rate risk. The currency exchange effect resulting from our international operations generally has not had a material impact on our operating results.

Credit risk—We are exposed to concentrations of credit risk primarily related to our restricted and unrestricted cash and cash equivalents and customer receivables. We generally maintain our restricted and unrestricted cash and cash equivalents in time deposits at commercial banks with high credit ratings or mutual funds, which invest exclusively in high-quality money market instruments, and because we limit the amount of exposure to any one institution, we do not believe we are exposed to any significant credit risk. Our customer receivables, dispersed across various countries, are due from integrated energy companies, government-owned or government-controlled energy companies and other independent energy companies. We occasionally require collateral or other security to support customer receivables when we have encountered isolated concerns related to the credit of independent energy companies. Additionally, in certain infrequent instances, when we determine that collection is uncertain, we may offer extended payment terms and recognize revenues associated with the contract on a cash basis. We establish an allowance for credit losses, recorded in accounts receivable, net, by applying an expected loss rate based on current, forecasted and historical experience. At December 31, 2025 and 2024, our allowance for credit losses was $2 million.

Labor agreements—At December 31, 2025, we had a global workforce of approximately 5,600 individuals, including approximately 380 contractors. Approximately 45 percent of our total workforce, working primarily in Brazil and Norway, is represented by, and some of our contracted labor work is subject to, collective bargaining agreements, substantially all of which are subject to annual salary negotiations. Negotiations for annual salary or other labor matters could result in higher personnel or other costs or increased operational restrictions or disruptions. The outcome of any such negotiation generally affects the market for all offshore employees, not only union members. A failure to reach an agreement on certain key issues could result in strikes, lockouts or other work stoppages.

- Definition

The entire disclosure for any concentrations existing at the date of the financial statements that make an entity vulnerable to a reasonably possible, near-term, severe impact. This disclosure informs financial statement users about the general nature of the risk associated with the concentration, and may indicate the percentage of concentration risk as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 21
-Subparagraph (d)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482907/825-10-50-21

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 21
-Subparagraph (d)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482907/825-10-50-21

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Section 50
-Paragraph 21
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-Publisher FASB
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
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Reference 9: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 275
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/275/tableOfContent

+ Details

Income Taxes (Deferred) (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Deferred tax assets
Net operating loss carryforwards	$ 1,985	$ 1,541
Swiss historic depreciation and financing asset costs	1,034	1,053
Interest expense limitation	54	87
United Kingdom charter limitation	53	53
Accrued costs and expenses	33	20
Contract liabilities	6	22
Accrued payroll expenses not currently deductible	11	12
Other	69	69
Valuation allowance	(2,479)	(2,089)
Total deferred tax assets, net of allowance	766	768
Deferred tax liabilities
Depreciation	(1,068)	(1,214)
Other	(41)	(8)
Total deferred tax liabilities	(1,109)	(1,222)
Deferred tax liabilities, net	(343)	(454)
U.S. foreign tax credit carryforwards	5	$ 5
NOLs that are not subject to expiration dates	1,570
NOLs that are subject to expiration dates	$ 563

Unconsolidated Affiliates (Related Party Transactions) (Details) - USD ($) shares in Millions, $ in Millions	1 Months Ended	12 Months Ended
	Sep. 30, 2023	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Liquila/Deepwater Aquila
Related party
Newly issued shares in asset acquisition (in shares)	11.9
Value shares issued in asset acquisition	$ 99		$ 431	$ 99
Liquila/Deepwater Aquila
Related party
Ownership interest (as a percent)	20.00%
Perestroika AS \| Liquila/Deepwater Aquila
Related party
Newly issued shares in asset acquisition (in shares)	2.0
Value shares issued in asset acquisition	$ 16
Perestroika AS \| Transocean Inc
Related party
Ownership interest (as a percent)	9.00%
Perestroika AS \| Liquila/Deepwater Aquila
Related party
Ownership interest (as a percent)	13.00%
Liquila/Deepwater Aquila \| Liquila/Deepwater Aquila
Related party
Equity ownership (as a percent)	80.00%
Orion/Transocean Norge
Related party
Equity ownership (as a percent)				33.00%
Non-cash net settlement of accounts receivable and payable				$ 25
Equity Method Investee
Related party
Related party transaction		$ 12	14	12
Long-term loans receivable from unconsolidated affiliates		$ 8	10
Services and Equipment \| Orion/Transocean Norge
Related party
Related party transaction			11	49
Rent Expense \| Orion/Transocean Norge
Related party
Related party transaction			25	26
Charter rig and other equipment \| Orion/Transocean Norge
Related party
Related party transaction			$ 25	$ 27

Income Taxes (Tax positions and returns) (Details) - 12 months ended Dec. 31, 2025 - BRAZIL R$ in Millions, $ in Millions	USD ($)	BRL (R$)
Corporate income tax
Income Tax Examination
Net adjustments of additional taxes, including interest and penalties	$ 95	R$ 523
Indirect tax
Income Tax Examination
Net adjustments of additional taxes, including interest and penalties	$ 17	R$ 96

Insider Trading Arrangements	3 Months Ended
Insider Trading Arrangements	Dec. 31, 2025
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false

Leases (Supplemental Cash Flow Information) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Leases
Operating cash flows from operating leases	$ 14	$ 20	$ 17
Operating cash flows from finance lease	6	4
Financing cash flows from finance lease	$ 12	$ 7

Equity (Share Issuance) (Details) - USD ($) shares in Millions, $ in Millions	1 Months Ended								12 Months Ended
	Sep. 30, 2025	Jun. 30, 2024	Oct. 31, 2023	Sep. 30, 2023	Jul. 31, 2023	Apr. 30, 2023	Aug. 31, 2022	Jun. 30, 2021	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Equity
Issuance of shares (in shares)	143.8
Proceeds from issuance of shares, net of issue costs	$ 421.0								$ 421.0
Shares issued upon conversion (in shares)									73.3		65.1
Debt issued in exchange transactions											$ 434.0
Perestroika AS \| Related party
Equity
Issuance of shares (in shares)	4.0
Proceeds from issuance of shares, net of issue costs	$ 12.0
2.50% Senior Guaranteed Exchangeable Bonds due January 2027
Equity
Shares issued upon conversion (in shares)					4.0	34.6
Debt issued in exchange transactions					$ 25.0	$ 213.0					$ 238.0
Debt instrument interest rate stated percentage					2.50%						2.50%
4.00% Senior Guaranteed Exchangeable Bonds due December 2025
Equity
Shares issued upon conversion (in shares)									73.3
Debt issued in exchange transactions			$ 60.0						$ 196.0
Debt instrument interest rate stated percentage			4.00%						4.00%		4.00%
4.625% Senior Guaranteed Exchangeable Bonds due September 2029
Equity
Debt issued in exchange transactions			$ 41.0
Debt instrument interest rate stated percentage			4.625%						4.625%		4.625%
ATM Program
Equity
Maximum value shares to be issued							$ 435.0	$ 400.0
Orion/Transocean Norge
Equity
Equity ownership (as a percent)											33.00%
Orion/Transocean Norge
Equity
Debt issued in exchange transactions									$ 201.0
Newly issued shares in asset acquisition (in shares)		55.5
Value shares issued in asset acquisition		$ 297.0
Orion/Transocean Norge \| Orion/Transocean Norge
Equity
Equity ownership (as a percent)		67.00%
Liquila/Deepwater Aquila
Equity
Newly issued shares in asset acquisition (in shares)				11.9
Value shares issued in asset acquisition				$ 99.0						$ 431.0	$ 99.0
Liquila/Deepwater Aquila \| Perestroika AS
Equity
Newly issued shares in asset acquisition (in shares)				2.0
Value shares issued in asset acquisition				$ 16.0
Liquila/Deepwater Aquila \| Liquila/Deepwater Aquila
Equity
Equity ownership (as a percent)				80.00%

Commitments and Contingencies (Letters of Credit and Surety Bonds) (Details) - Letters of credit and surety bonds - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Letters of credit and surety bonds
Outstanding letters of credit	$ 51	$ 9
Outstanding surety bonds	128	147
Aggregate cash collateral	$ 3	$ 8

Share-Based Compensation (Overview) (Details) shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2025 USD ($) shares
Share Based Compensation
Shares authorized under the plan	154.2
Shares available for grant under the plan	37.3
Total unrecognized compensation costs unvested share based awards \| $	$ 33
Weighted average period over compensation costs are expected to be recognized	1 year 8 months 12 days
Service awards
Share Based Compensation
Vesting period	3 years
General term of awards after they are vested	7 years
Performance awards
Share Based Compensation
Measurement period	3 years

Revenues (Tables)

12 Months Ended

Dec. 31, 2025

Revenues.

Schedule of revenue disaggregation

Our contract drilling revenues, disaggregated by asset group and by country in which they were earned, were as follows (in millions):


	Year ended December 31, 2025						Year ended December 31, 2024						Year ended December 31, 2023
	Ultra-		Harsh				Ultra-		Harsh				Ultra-		Harsh
	deepwater		environment				deepwater		environment				deepwater		environment
	floaters		floaters		Total		floaters		floaters		Total		floaters		floaters		Total
U.S.	$	1,635	$	—	$	1,635	$	1,566	$	—	$	1,566	$	1,433	$	—	$	1,433
Brazil		872		—		872		727		—		727		298		—		298
Norway		—		639		639		—		654		654		—		603		603
Other countries (a)		270		549		819		225		352		577		341		157		498
Total contract drilling revenues	$	2,777	$	1,188	$	3,965	$	2,518	$	1,006	$	3,524	$	2,072	$	760	$	2,832

(a)	The aggregate contract drilling revenues earned in other countries that individually represented less than 10 percent of total contract drilling revenues.

Schedule of contract balances and changes

Contract liabilities for our contracts with customers were as follows (in millions):


		December 31,
		2025			2024
Deferred contract revenues, recorded in other current liabilities		$	181		$	231
Deferred contract revenues, recorded in other long-term liabilities			92			212
Total contract liabilities		$	273		$	443

Significant changes in contract liabilities were as follows (in millions):


		Years ended December 31,
		2025			2024
Total contract liabilities, beginning of period		$	443		$	398
Decrease due to recognition of revenues for goods and services			(260)			(243)
Increase due to goods and services transferred over time			90			288
Total contract liabilities, end of period		$	273		$	443

Schedule II - Valuation and Qualifying Accounts

12 Months Ended

Dec. 31, 2025

Schedule II - Valuation and Qualifying Accounts

Schedule II - Valuation and Qualifying Accounts

Transocean Ltd. and Subsidiaries

Schedule II—Valuation and Qualifying Accounts

(in millions)


		Years ended December 31,
		2025		2024		2023
Allowance for credit losses
Balance, beginning of period		$	2	$	2	$	2
Additions: charged to cost and expenses			—		—		—
Additions: charged to other accounts			—		—		—
Deductions			—		—		—
Balance, end of period		$	2	$	2	$	2

Allowance for excess materials and supplies
Balance, beginning of period		$	178	$	198	$	199
Additions: charged to cost and expenses			17		7		6
Additions: charged to other accounts			—		—		—
Deductions	(a)		(55)		(27)		(7)
Balance, end of period		$	140	$	178	$	198

Valuation allowance on deferred tax assets
Balance, beginning of period		$	2,089	$	1,884	$	1,910
Additions: charged to cost and expenses			390		208		—
Additions: charged to other accounts			—		—		—
Deductions	(b)		—		(3)		(26)
Balance, end of period		$	2,479	$	2,089	$	1,884

(a)	Amount related to disposal of materials and supplies, primarily associated with rigs and related assets sold or classified as held for sale.

(b)	Amount related to adjustments to other deferred tax assets with valuation allowances.

Supplemental Segment information

12 Months Ended

Dec. 31, 2025

Supplemental Segment information

Supplemental Segment information

Note 15—Supplemental Segment information

Our Chief Executive Officer serves as our chief operating decision maker (“CODM”) and assesses performance for and allocates resources for our single contract drilling services segment based on our consolidated net income or loss, as presented on our consolidated statements of operations. The significant segment expense categories regularly provided to our CODM include our operating and maintenance costs and our general and administrative costs, as presented on our consolidated statements of operations. Other segment items included in our consolidated net income or loss include depreciation and amortization, loss on impairment of assets, gain or loss on disposal of assets, interest expense and income tax expense or benefit. Additionally, our CODM reviews our segment assets, as presented on our consolidated balance sheets.

Our CODM uses our consolidated results of operations to evaluate income or loss generated from segment assets, or return on assets, to make decisions to deploy cash flows from operations for reinvestment in our contract drilling services segment or for other uses, such as for acquisitions, debt and equity investments, liability management or to pay dividends to our shareholders. Consolidated results of operations are used to monitor actual results relative to historical, budgeted and forecasted results and to assess segment performance against our peers.

- Definition

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

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+ Details

Loss Per Share (Basic and Diluted) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Numerator for loss per share, basic
Net Income (Loss)	$ (2,915)	$ (512)	$ (954)
Loss for per share calculation, basic	$ (2,915)	$ (512)	$ (954)
Denominator for loss per share, basic
Weighted-average shares outstanding (in shares)	960	850	768
Weighted-average shares for per share calculation, basic (in shares)	960	850	768
Loss per share, basic (in dollars per share)	$ (3.04)	$ (0.6)	$ (1.24)
Numerator for loss per share, diluted
Net Income (Loss)	$ (2,915)	$ (512)	$ (954)
Effect of convertible debt instruments, net of tax		(189)
Loss for per share calculation, diluted	$ (2,915)	$ (701)	$ (954)
Numerator for loss per share, diluted
Weighted-average shares outstanding (in shares)	960	850	768
Effect of convertible debt instruments (in shares)		75
Weighted-average shares for per share calculation, diluted (in shares)	960	925	768
Loss per share, diluted (in dollars per share)	$ (3.04)	$ (0.76)	$ (1.24)
Exchangeable bonds
Anti-dilutive securities
Securities excluded from earnings per share calculation (in shares)	102	45	151
Share-based awards
Anti-dilutive securities
Securities excluded from earnings per share calculation (in shares)	8	11	19
Warrants
Anti-dilutive securities
Securities excluded from earnings per share calculation (in shares)		6	10

Supplemental Balance Sheet Information (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Other current liabilities
Accrued employee benefits and payroll-related liabilities	$ 166	$ 136
Accrued interest	101	134
Accrued taxes, other than income	28	39
Finance lease liability	$ 51	$ 47
Finance Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Total other current liabilities	Total other current liabilities
Operating lease liabilities	$ 8	$ 7
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Total other current liabilities	Total other current liabilities
Contract liabilities	$ 181	$ 231
Contingent liabilities	87	94
Other	5	3
Total other current liabilities	627	691
Other long-term liabilities
Postemployment benefit plan obligations	103	100
Finance lease liability	$ 169	$ 224
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration]	Total other long-term liabilities	Total other long-term liabilities
Operating lease liabilities	$ 86	$ 88
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration]	Total other long-term liabilities	Total other long-term liabilities
Income taxes payable	$ 90	$ 65
Contract liabilities	92	212
Other	42	40
Total other long-term liabilities	$ 582	$ 729

Commitments and Contingencies (Service Agreement Obligations) (Details) - Supply agreement $ in Millions	Dec. 31, 2025 USD ($)
Future Purchase obligations
2026	$ 140
2027	117
2028	73
2029	51
2030	31
Thereafter	66
Total	$ 478

Supplemental Cash Flow Information

12 Months Ended

Dec. 31, 2025

Supplemental Cash Flow Information

Supplemental Cash Flow Information

Note 17—Supplemental Cash Flow Information

The reconciling adjustments of our net cash provided by operating activities that were attributable to the net change in other operating assets and liabilities were as follows (in millions):


		Years ended December 31,
		2025			2024			2023
Changes in other operating assets and liabilities
Increase in accounts receivable		$	(30)		$	(94)		$	(99)
(Increase) decrease in other assets			7			(92)			(91)
Increase (decrease) in accounts payable and other current liabilities			(12)			(86)			144
Decrease in other long-term liabilities			(7)			(3)			(6)
Change in income taxes receivable / payable, net			17			(19)			(36)
Change in receivables from / payables to affiliates, net			—			9			(8)
		$	(25)		$	(285)		$	(96)

Additional cash flow information was as follows (in millions):


			Years ended December 31,
			2025			2024			2023
Certain cash operating activities
Cash payments for interest			$	538		$	521		$	408

Noncash investing and financing activities
Capital additions accrued at end of period	(a)		$	20		$	23		$	36
Acquisition of outstanding ownership interests in exchange for shares and debt	(b)			—			431			99
Debt investment exchanged for equity ownership interests	(c)			2			—			37
Finance lease installments settled with credits issued to customer	(d)			39			40			44
Shares issued in exchanges of exchangeable bonds	(e)			201			—			434

(a)	Additions to property and equipment for which we had accrued a corresponding liability in accounts payable at the end of the period. See Note 6—Long-Lived Assets.

(b)

(c)

(d)	In the years ended December 31, 2025, 2024 and 2023, we agreed to settle installments due to the lessor under our finance lease by issuing corresponding credits to our customer for amounts due to us under the drilling contract. See Note 7—Leases.

(e)

CONSOLIDATED STATEMENTS OF EQUITY - USD ($) shares in Millions, $ in Millions	Total controlling interest shareholders' equity	Shares	Additional paid-in capital	Accumulated deficit	Accumulated other comprehensive loss	Noncontrolling interest	Total
Balance, beginning at Dec. 31, 2022	$ 10,791	$ 71	$ 13,984	$ (3,079)	$ (185)	$ 1	$ 10,792
Balance, beginning (in shares) at Dec. 31, 2022		722
Increase (Decrease) in Shareholders' Equity
Total comprehensive loss attributable to controlling interest	(946)						(946)
Total comprehensive loss							(946)
Share-based compensation	40		40				40
Issuance of shares	530	$ 10	520				530
Issuance of shares (in shares)		87
Net Income (Loss)				(954)			(954)
Other comprehensive income (loss) attributable to controlling interest					8		8
Balance, end at Dec. 31, 2023	10,415	$ 81	14,544	(4,033)	(177)	1	10,416
Balance, end (in shares) at Dec. 31, 2023		809
Increase (Decrease) in Shareholders' Equity
Total comprehensive loss attributable to controlling interest	(473)						(473)
Total comprehensive loss							(473)
Share-based compensation	47		47				47
Issuance of shares	295	$ 6	289				295
Issuance of shares (in shares)		67
Net Income (Loss)				(512)			(512)
Other comprehensive income (loss) attributable to controlling interest					39		39
Balance, end at Dec. 31, 2024	10,284	$ 87	14,880	(4,545)	(138)	1	10,285
Balance, end (in shares) at Dec. 31, 2024		876
Increase (Decrease) in Shareholders' Equity
Total comprehensive loss attributable to controlling interest	(2,923)						(2,923)
Total comprehensive loss							(2,923)
Share-based compensation	35		35				35
Issuance of shares	712	$ 23	689				712
Issuance of shares (in shares)		226
Net Income (Loss)				(2,915)			(2,915)
Other comprehensive income (loss) attributable to controlling interest					(8)		(8)
Distribution to holder of noncontrolling interest						$ (1)	(1)
Balance, end at Dec. 31, 2025	$ 8,108	$ 110	$ 15,604	$ (7,460)	$ (146)		$ 8,108
Balance, end (in shares) at Dec. 31, 2025		1,102

Debt (Interest Expense) (Details) - USD ($) $ in Millions	12 Months Ended
Debt (Interest Expense) (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Interest Expense
Amortization	$ 48	$ 53	$ 51
(Gain) loss on adjustment to bifurcated compound exchange feature	(10)	(214)	127
Total	555	362	646
Exchangeable bonds
Interest Expense
Contractual interest	18	21	24
Amortization	20	20	19
(Gain) loss on adjustment to bifurcated compound exchange feature	(10)	(214)	127
Total	$ 28	$ (173)	$ 170

- Definition

The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of derivative instruments, including options, swaps, futures, and forward contracts, held at each balance sheet date, that was included in earnings for the period.

+ References + Details

CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS
Net loss	$ (2,915)	$ (512)	$ (954)
Net loss attributable to controlling interest	(2,915)	(512)	(954)
Components of net periodic benefit costs before reclassifications	(9)	37	6
Components of net periodic benefit costs reclassified to net loss	1	2
Other comprehensive income (loss) before income taxes	(8)	39	6
Income taxes related to other comprehensive income (loss)			2
Other comprehensive income (loss)	(8)	39	8
Other comprehensive income (loss) attributable to controlling interest	(8)	39	8
Total comprehensive loss	(2,923)	(473)	(946)
Total comprehensive loss attributable to controlling interest	$ (2,923)	$ (473)	$ (946)

Commitments and Contingencies

12 Months Ended

Dec. 31, 2025

Commitments and Contingencies.

Commitments and Contingencies

Note 12—Commitments and Contingencies

Service agreement obligations

We have long-term service agreements with original equipment manufacturers to provide services and parts, primarily related to our pressure control systems and drilling systems. We estimated the commitments for our service agreements based on projected operating activity, and actual operating activity could differ from such estimates. At December 31, 2025, the aggregate future payments required under our service agreement obligations were as follows (in millions):


		Service
		agreement
		obligations
Years ending December 31,
2026		$	140
2027			117
2028			73
2029			51
2030			31
Thereafter			66
Total		$	478

Letters of credit and surety bonds

At December 31, 2025 and 2024, we had outstanding letters of credit totaling $51 million and $9 million, respectively, issued under various committed and uncommitted credit lines provided by banks to guarantee certain performance activities, tax commitments and customs or other obligations. At December 31, 2025 and 2024, we also had outstanding surety bonds totaling $128 million and $147 million, respectively, to secure certain tax commitments and other obligations. At December 31, 2025 and 2024, the aggregate cash collateral held by institutions to secure our letters of credit and surety bonds was $3 million and $8 million, respectively.

Legal proceedings

Asbestos litigation—In 2014, several of our subsidiaries were named, along with numerous other unaffiliated defendants, in complaints filed in Louisiana. The plaintiffs, former employees of some of the defendants, generally allege that the defendants used or manufactured asbestos-containing drilling mud additives for use in connection with drilling operations, claiming negligence, products liability, strict liability and claims allowed under the Jones Act and general maritime law. One of our subsidiaries has been named in similar complaints filed in Illinois, Missouri and California. At December 31, 2025, two plaintiffs have claims pending in Louisiana and 30 plaintiffs in the aggregate have claims pending in Illinois, Missouri, and California, in which we have or may have an interest. We intend to defend these lawsuits vigorously, although we can provide no assurance as to the outcome. We historically have maintained broad liability insurance, although we can provide no assurance as to whether insurance will cover the liabilities, if any, arising out of these claims. Based on our evaluation of the exposure to date, we do not expect the liability, if any, resulting from these claims to have a material adverse effect on our consolidated statement of financial position, results of operations or cash flows.

One of our subsidiaries was named as a defendant, along with numerous other companies, in lawsuits arising out of the subsidiary’s manufacture and sale of heat exchangers, and involvement in the construction and refurbishment of major industrial complexes alleging bodily injury or personal injury as a result of exposure to asbestos. As of December 31, 2025, the subsidiary was a defendant in approximately 405 lawsuits with a corresponding number of plaintiffs. For many of these lawsuits, we have not been provided sufficient information from the plaintiffs to determine whether all or some of the plaintiffs have claims against the subsidiary, the basis of any such claims, or the nature of their alleged injuries. The operating assets of the subsidiary were sold in 1989. We have a coverage-in-place agreement with certain insurers and additional funding from settlement agreements with other insurers. Overall, we believe the subsidiary has sufficient resources to respond to both the current lawsuits as well as future lawsuits of a similar nature. While we cannot predict or provide assurance as to the outcome of these matters, we do not expect the ultimate liability, if any, resulting from these claims to have a material adverse effect on our consolidated statement of financial position, results of operations or cash flows.

Other matters—We are involved in various regulatory matters and a number of claims and lawsuits, asserted and unasserted, all of which have arisen in the ordinary course of our business. We do not expect the liability, if any, resulting from these other matters to have

a material adverse effect on our consolidated statement of financial position, results of operations or cash flows. We cannot predict with certainty the outcome or effect of any of the litigation matters specifically described above or of any such other pending, threatened, or possible litigation or liability. We can provide no assurance that our beliefs or expectations as to the outcome or effect of any tax, regulatory, lawsuit or other litigation matter will prove correct and the eventual outcome of these matters could materially differ from management’s current estimates.

Environmental matters

We have certain potential liabilities under the Comprehensive Environmental Response, Compensation, and Liability Act (“CERCLA”) and similar state acts regulating cleanup of hazardous substances at various waste disposal sites, including those described below. CERCLA is intended to expedite the remediation of hazardous substances without regard to fault. Potentially responsible parties (“PRPs”) for each site include present and former owners and operators of, transporters to and generators of the substances at the site. It is difficult to quantify the potential cost of environmental matters and remediation obligations. Liability is strict and can be joint and several.

One of our subsidiaries was named as a PRP in connection with a site located in Santa Fe Springs, California, known as the Waste Disposal, Inc. site. We and other PRPs agreed, under a participation agreement with the U.S. Environmental Protection Agency (the “EPA”) and the U.S. Department of Justice, to settle our potential liabilities by remediating the site. The remedial action for the site was completed in 2006. Our share of the ongoing operating and maintenance costs has been insignificant, and we do not expect any additional potential liabilities to be material. Resolutions of other claims by the EPA, the involved state agency or PRPs are at various stages of investigation. Nevertheless, based on available information with respect to all environmental matters, including all related pending legal proceedings, asserted legal claims and known potential legal claims that are likely to be asserted, we do not expect the ultimate liability, if any, resulting from such matters, to have a material adverse effect on our consolidated statement of financial position, results of operations or cash flows.

Share-Based Compensation (Stock Options) (Details) - Service awards - Employee Stock Option - $ / shares	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Stock option activity
Outstanding at the beginning of the period (in shares)	4,069,334
Forfeited (in shares)	(17,006)
Outstanding at the end of the period (in shares)	4,052,328	4,069,334
Vested and exercisable at the end of the period (in shares)	4,052,328
Weighted-average exercise price per share
Outstanding at the beginning of the period (in dollars per share)	$ 9.53
Forfeited (in dollars per share)	8.35
Outstanding at the end of the period (in dollars per share)	9.54	$ 9.53
Vested and exercisable at the end of the period (in dollars per share)	$ 9.54
Additional disclosure
Weighted-average remaining contractual term, outstanding	1 year 11 months 1 day	2 years 11 months 4 days
Weighted-average remaining contractual term, vested and exercisable at the end of the period	1 year 11 months 1 day
Unvested stock options outstanding (in shares)	0	0	0

Debt

12 Months Ended

Dec. 31, 2025

Debt

Debt

Note 8—Debt

Overview

Outstanding debt—The aggregate principal amounts and aggregate carrying amounts, including a bifurcated compound exchange feature and unamortized debt-related balances, such as discounts, premiums and issue costs, were as follows (in millions):


		Principal amount					Carrying amount
		December 31,			December 31,		December 31,			December 31,
		2025			2024		2025			2024
4.00% Senior Guaranteed Exchangeable Bonds due December 2025	(a)	$	—		$	234	$	—		$	227
6.875% Senior Secured Notes due February 2027	(b)		—			330		—			328
8.00% Senior Notes due February 2027	(c)		—			655		—			653
7.45% Notes due April 2027	(d)		52			52		52			52
8.00% Debentures due April 2027	(d)		22			22		22			22
4.50% Shipyard Loans due September 2027	(e)		209			329		202			310
8.375% Senior Secured Notes due February 2028	(b)		425			525		421			518
7.00% Notes due June 2028	(e)		209			261		210			263
8.00% Senior Secured Notes due September 2028	(b)		235			295		233			292
8.25% Senior Notes due May 2029	(c)		900			900		889			887
4.625% Senior Guaranteed Exchangeable Bonds due September 2029	(c)		259			259		292			286
8.75% Senior Secured Notes due February 2030	(f)		881			999		868			981
7.50% Notes due April 2031	(d)		396			396		395			395
8.50% Senior Notes due May 2031	(c)		900			900		888			886
7.875% Senior Guaranteed Notes due October 2032	(a)		500			—		493			—
6.80% Senior Notes due March 2038	(d)		610			610		605			605
7.35% Senior Notes due December 2041	(d)		88			177		87			176
Total debt			5,686			6,944		5,657			6,881

Less debt due within one year
4.00% Senior Guaranteed Exchangeable Bonds due December 2025	(a)		—			234		—			227
6.875% Senior Secured Notes due February 2027	(b)		—			83		—			82
4.50% Shipyard Loans due September 2027	(e)		136			120		129			108
8.375% Senior Secured Notes due February 2028	(b)		135			100		133			97
8.00% Senior Secured Notes due September 2028	(b)		70			60		69			59
8.75% Senior Secured Notes due February 2030	(f)		117			117		114			113
Total debt due within one year			458			714		445			686
Total long-term debt		$	5,228		$	6,230	$	5,212		$	6,195

(a)

Transocean International Limited, a wholly owned direct subsidiary of Transocean Ltd., is the issuer of the unregistered notes (together, the “Senior Priority Guaranteed Notes”). The priority guaranteed senior unsecured notes are fully and unconditionally, jointly and severally, guaranteed by Transocean Ltd. and certain wholly owned indirect subsidiaries of Transocean International Limited and rank equal in right of payment of all of our existing and future unsecured unsubordinated obligations. Such notes are structurally senior to the Priority Guaranteed Notes, as defined below, to the extent of the value of the assets of the subsidiaries guaranteeing the notes.

(b)

Each subsidiary issuer of the respective unregistered notes is a wholly owned indirect subsidiary of Transocean International Limited. The senior secured notes are fully and unconditionally, jointly and severally, guaranteed by Transocean Ltd., Transocean International Limited and, in each case, the owner of the respective collateral rig or rigs.

(c)

Transocean International Limited is the issuer of the unregistered notes (collectively, the “Priority Guaranteed Notes”). The guaranteed senior unsecured notes are fully and unconditionally, jointly and severally, guaranteed by Transocean Ltd. and certain wholly owned indirect subsidiaries of Transocean International Limited and rank equal in right of payment of all our existing and future unsecured unsubordinated obligations. Such notes are structurally senior

to the Legacy Guaranteed Notes, as defined below, the 4.50% shipyard loans due September 2027 (each, a “Shipyard Loan”, and together, the “Shipyard Loans”) and the 7.00% notes due June 2028 and structurally subordinate to the Senior Priority Guaranteed Notes to the extent of the value of the assets of the subsidiaries guaranteeing the notes.

(d)	Transocean International Limited is the issuer of the notes and debentures (the “Legacy Guaranteed Notes”). The Legacy Guaranteed Notes are fully and unconditionally, jointly and severally, guaranteed by Transocean Ltd.

(e)	The subsidiary borrowers under the Shipyard Loans and the subsidiary issuer of the registered notes are wholly owned indirect subsidiaries of Transocean International Limited. The loans and notes are fully and unconditionally guaranteed by Transocean International Limited.

(f)	Transocean International Limited is the issuer of the unregistered notes. The senior secured notes are fully and unconditionally guaranteed on an unsecured basis by Transocean Ltd. and on a limited senior secured basis by each of the wholly owned subsidiary owners of the collateral rigs.

Indentures—The indentures that govern our debt generally contain covenants that, among other things, limit our ability to incur certain liens on our drilling units without equally and ratably securing the notes, to engage in certain sale and lease back transactions covering any of our drilling units, to allow our subsidiaries to incur certain additional debt, or to engage in certain merger, consolidation or reorganization transactions or to enter into a scheme of arrangement qualifying as an amalgamation. Transocean Ltd. and Transocean International Limited are not subject to any significant restrictions on their ability to obtain funds from their consolidated subsidiaries by dividends, loans or capital distributions.

The indenture that governs the 4.625% senior guaranteed exchangeable bonds due September 2029 (the “4.625% Exchangeable Bonds”) requires such bonds to be repurchased upon the occurrence of certain fundamental changes and events, at specified prices depending on the particular fundamental change or event, which include changes and events related to certain (i) change of control events applicable to Transocean Ltd. or Transocean International Limited, (ii) the failure of our shares to be listed or quoted on a national securities exchange and (iii) specified tax matters.

The indentures that govern the 8.375% senior secured notes due February 2028 (the “8.375% Senior Secured Notes”), the 8.00% senior secured notes due September 2028 (the “8.00% Senior Secured Notes”) and the 8.75% senior secured notes due February 2030 (the “8.75% Senior Secured Notes”) contain certain covenants, among others, related to the debt and earnings attributable to the collateral rigs and the ability of our subsidiaries that own or operate the collateral rigs to declare or pay dividends to their affiliates. We will be required to redeem the senior secured notes at a price equal to 100 percent of the aggregate principal amount without a make-whole premium, upon the occurrence of certain events related to the respective collateral rigs and related drilling contracts. The indentures that govern our senior secured notes contain certain lien requirements, including the maintenance of certain balances in a restricted cash account to satisfy debt service requirements.

Assets encumbered for outstanding debt—At December 31, 2025, the rigs encumbered for the senior secured notes and our Shipyard Loans include the ultra-deepwater drillships Deepwater Aquila, Deepwater Atlas, Deepwater Pontus, Deepwater Proteus, Deepwater Thalassa, Deepwater Titan, and the harsh environment semisubmersibles Transocean Enabler and Transocean Encourage, the aggregate carrying amount of which was $5.19 billion. At December 31, 2025, we had restricted cash and cash equivalents of $358 million deposited in restricted accounts to satisfy debt service and reserve requirements for the senior secured notes.

Interest rate adjustments—At December 31, 2025, the interest rate in effect for the 7.35% senior notes due December 2041 was 9.35 percent, which is subject to adjustment from time to time upon a change to the credit rating of our non-credit enhanced senior unsecured long-term debt.

Scheduled maturities and installments—At December 31, 2025, the scheduled repayments were as follows (in millions):


		Total
Years ending December 31,
2026		$	458
2027			435
2028			612
2029			1,277
2030			411
Thereafter			2,493
Total principal amount of debt			5,686
Total unamortized debt-related balances, net			(155)
Bifurcated compound exchange feature, at estimated fair value			126
Total carrying amount of debt		$	5,657

Credit agreements

Secured Credit Facility—As of December 31, 2025, we have a secured revolving credit facility established under a bank credit agreement (as amended from time to time, the “Secured Credit Facility”), which has a borrowing capacity of $510 million through its maturity on June 22, 2028. Throughout the term of the Secured Credit Facility, we pay a facility fee on the amount of the underlying commitment, which ranges from 0.375 percent to 1.00 percent based on the credit rating of the Secured Credit Facility. We may borrow under the Secured Credit Facility at a forward-looking term rate based on the secured overnight financing rate (“Term SOFR”) plus a margin and a Term SOFR

spread adjustment of 0.10 percent. The Secured Credit Facility is subject to permitted extensions and certain early maturity triggers, including if on any date the aggregate amount of scheduled principal repayments of indebtedness, with certain exceptions, due within 91 days thereof is equal to or in excess of $325 million and available cash is less than $250 million. The Secured Credit Facility permits us to increase the aggregate amount of commitments by up to $250 million. The Secured Credit Facility is guaranteed by Transocean Ltd. and certain wholly owned subsidiaries. The Secured Credit Facility is secured by, among other things, a lien on the ultra-deepwater drillships Deepwater Asgard, Deepwater Conqueror, Deepwater Corcovado, Deepwater Invictus, Deepwater Mykonos, Deepwater Orion, Deepwater Skyros and Dhirubhai Deepwater KG2 and the harsh environment semisubmersibles Transocean Barents and Transocean Spitsbergen, and at December 31, 2025, the aggregate carrying amount of which was $4.18 billion.

The Secured Credit Facility contains covenants that, among other things, include maintenance of a minimum guarantee coverage ratio of 3.0 to 1.0, a minimum collateral coverage ratio of 2.1 to 1.0, a maximum debt to capitalization ratio of 0.60 to 1.00 and minimum liquidity of $200 million. The Secured Credit Facility also restricts the ability of Transocean Ltd. and certain of our subsidiaries to, among other things, merge, consolidate or otherwise make changes to the corporate structure, incur liens, incur additional indebtedness, enter into transactions with affiliates and permits, subject to certain conditions, the ability to pay dividends and repurchase our shares. In order to utilize the Secured Credit Facility, we must, at the time of the borrowing request, be in full compliance with the terms and conditions of the Secured Credit Facility and make certain representations and warranties, including with respect to compliance with laws and solvency, to the lenders. Repayment of borrowings under the Secured Credit Facility are subject to acceleration upon the occurrence of an event of default. Under the agreements governing certain of our debt and finance lease, we are also subject to various covenants, including restrictions on creating liens, engaging in sale/leaseback transactions and engaging in certain merger, consolidation or reorganization transactions. A default under our public debt indentures, the agreements governing our senior secured notes, our finance lease contract or any other debt owed to unaffiliated entities that exceeds $125 million could trigger a default under the Secured Credit Facility and, if not waived by the lenders or otherwise cured, could cause us to lose access to the Secured Credit Facility. At December 31, 2025, based on the credit rating of the Secured Credit Facility as of that date, the Secured Credit Facility Margin was 2.875 percent and the facility fee was 0.625 percent. At December 31, 2025, we had no borrowings outstanding, $48 million of letters of credit issued, and we had $462 million of available borrowing capacity under the Secured Credit Facility.

Shipyard financing arrangement—We have credit agreements that established the Shipyard Loans to finance all or a portion of the final payments owed to the shipyard when we took delivery of Deepwater Atlas and Deepwater Titan in the year ended December 31, 2022 The Shipyard Loans contain covenants that, among other things, limit the ability of the subsidiary owners of the drilling rigs to incur certain types of additional indebtedness or make certain additional commitments or investments. We have the right to prepay outstanding borrowings, in full or in part, without penalty. At December 31, 2025, the Shipyard Loan for Deepwater Atlas had outstanding borrowings of $159 million, which are secured by, among other security, a lien on the rig, and the Shipyard Loan for Deepwater Titan had outstanding borrowings of $50 million, which are unsecured.

Exchangeable bonds

Interest expense—We recognized interest expense for our exchangeable bonds as follows (in millions):


		Years ended December 31,
	2025		2024		2023
Contractual interest	$	18	$	21	$	24
Amortization		20		20		19
(Gain) loss on adjustment to bifurcated compound exchange feature		(10)		(214)		127
Total	$	28	$	(173)	$	170

On or after March 30, 2026, we may redeem for cash all or a portion of the 4.625% Exchangeable Bonds at a price equivalent to the aggregate principal amount to be redeemed if the closing price of our shares has been greater than 115 percent of the exchange price for a period of at least 20 trading days. If we give notice of our election to exercise the right to redeem, the indenture governing the 4.625% Exchangeable Bonds contains a compound exchange feature that, in addition to the exchange terms presented below, requires us to pay a make-whole premium of future interest through March 30, 2028 to any holders that exercise their right to exchange during the redemption notice period. Such compound exchange feature must be bifurcated from the host debt instrument since it is not considered indexed to our stock. Accordingly, we recognize changes to the liability for the estimated fair value of the bifurcated compound exchange feature with a corresponding adjustment to interest expense. At December 31, 2025 and 2024, the carrying amount of the bifurcated compound exchange feature, recorded as a component of the carrying amount of debt, was $126 million and $136 million, respectively.

Effective interest rate and fair value—At December 31, 2025, the 4.625% Exchangeable Bonds had an effective interest rate of 18.3% and an estimated fair value of $355 million. We estimated the fair value of the exchangeable debt instrument, including the exchange feature, by employing a binomial lattice model using significant other observable inputs, representative of Level 2 fair value measurements, including the terms and credit spreads of our debt and the expected volatility of the market price for our shares.

Exchange terms—At December 31, 2025, the 4.625% Exchangeable Bonds had the following exchange terms: (a) an exchange rate of 290.6618 Transocean Ltd. shares per $1,000 note, (b) an implied exchange price of $3.44 per Transocean Ltd. share and (c) an aggregate of 75.3 million shares issuable upon exchange of our exchangeable bonds. The exchange rate is subject to adjustment upon the

occurrence of certain events. The 4.625% Exchangeable Bonds may be exchanged by holders at any time prior to the close of business on the second business day immediately preceding the maturity date or redemption date and, at our election, such exchange may be settled by delivering cash, Transocean Ltd. shares or a combination of cash and shares.

Exchanges—In the year ended December 31, 2025, we entered into separate, individually negotiated agreements (as amended, the “Exchange Agreements”) with certain holders of the 4.00% senior guaranteed exchangeable bonds due December 2025 (the “4.00% Exchangeable Bonds”). In the year ended December 31, 2025, the holders exchanged $196 million aggregate principal amount of 4.00% Exchangeable Bonds under the terms of the Exchange Agreements and received an aggregate 73.3 million Transocean Ltd. shares, which included an aggregate 35.9 million shares incremental to the number of shares issuable pursuant to the governing indenture based upon the principal amount exchanged. In the year ended December 31, 2025, we recognized a loss of $99 million, recorded in other, net, associated with these exchanges.

In the year ended December 31, 2023, holders of the outstanding $238 million aggregate principal amount of 2.50% senior guaranteed exchangeable bonds due January 2027 (the “2.50% Exchangeable Bonds”) exchanged such bonds under the terms of the governing indenture at the applicable exchange rate of 162.1626 Transocean Ltd. shares per $1,000 note. In April 2023, as part of the transactions, we delivered 34.6 million Transocean Ltd. shares, together with $3 million cash consideration, for $213 million aggregate principal amount of exchanged bonds in a related party transaction with Perestroika. In the year ended December 31, 2023, we recognized a loss of $3 million, recorded in other, net, associated with these exchanges. The director’s beneficial ownership of our shares resulting from the related party transaction did not change. In July 2023, we delivered 4.0 million Transocean Ltd. shares to holders of the remaining $25 million aggregate principal amount of 2.50% Exchangeable Bonds.

Additionally, in October 2023, holders of $60 million and $41 million aggregate principal amount of 4.00% Exchangeable Bonds and 4.625% Exchangeable Bonds, respectively, exchanged such bonds under the terms of the governing indenture at the applicable exchange rate of 190.4762 and 290.6618 Transocean Ltd. shares, respectively, per $1,000 note. As part of the transactions, we delivered an aggregate 26.5 million Transocean Ltd. shares, including an aggregate 3.1 million shares incremental to the number of shares issuable pursuant to the governing indenture. In the year ended December 31, 2023, we recognized a loss of $24 million, recorded in other, net, associated with these transactions.

Debt issuance

Senior notes—In October 2025, we issued $500 million aggregate principal amount of 7.875% senior guaranteed notes due October 2032 (the “7.875% Senior Guaranteed Notes”) and received $492 million aggregate cash proceeds, net of issue costs. The 7.875% Senior Guaranteed Notes are fully and unconditionally guaranteed on a senior unsecured basis by Transocean Ltd. and certain of our wholly owned subsidiaries. Prior to October 15, 2028, we may redeem up to 40 percent of the aggregate principal amount of the 7.875% Senior Guaranteed Notes at a price equal to 107.875 percent, or we may redeem all or a portion at a price equal to 100 percent of the aggregate principal amount plus a make-whole premium. On or after October 15, 2028, we may redeem the notes at specified redemption prices.

In April 2024, we issued $900 million aggregate principal amount of 8.25% senior notes due May 2029 (the “8.25% Senior Notes”) and $900 million aggregate principal amount of 8.50% senior notes due May 2031 (the “8.50% Senior Notes”), and we received $1.77 billion aggregate cash proceeds, net of issue costs. The 8.25% Senior Notes and the 8.50% Senior Notes are fully and unconditionally guaranteed on a senior unsecured basis by Transocean Ltd. and certain of our wholly owned subsidiaries. On or prior to May 15, 2026 and 2027, respectively, we may redeem all or a portion of the 8.25% Senior Notes and the 8.50% Senior Notes, respectively, at a price equal to 100 percent of the aggregate principal amount plus a make-whole premium, and subsequently, at specified redemption prices.

In June 2024, as partial consideration to acquire the outstanding 67.0 percent ownership interest in Orion, we issued $130 million aggregate principal amount of 8.00% Senior Notes, with an equivalent aggregate fair value, as additional debt securities under the indenture governing such notes. See Note 4—Unconsolidated Affiliates, Note 6—Long-Lived Assets and Note 13—Equity.

Senior secured notes—In January 2023, we issued $525 million aggregate principal amount of 8.375% Senior Secured Notes, and we received $516 million aggregate cash proceeds, net of issue costs. The 8.375% Senior Secured Notes are secured by the assets and earnings associated with Deepwater Titan and the equity of the wholly owned subsidiary that owns or operates the collateral rig. We may redeem all or a portion of the 8.375% Senior Secured Notes at specified redemption prices.

In January 2023, we issued $1.175 billion aggregate principal amount of 8.75% Senior Secured Notes, and we received $1.148 billion aggregate cash proceeds, net of issue costs. The 8.75% Senior Secured Notes are secured by a lien on Deepwater Pontus, Deepwater Proteus, Deepwater Thalassa, Transocean Enabler and Transocean Encourage, together with certain related assets. We may redeem all or a portion of the 8.75% Senior Secured Notes at specified redemption prices.

In October 2023, we issued $325 million aggregate principal amount of 8.00% Senior Secured Notes, and we received $319 million aggregate cash proceeds, net of issue costs. The 8.00% Senior Secured Notes are secured by the assets and certain earnings associated with Deepwater Aquila as well as the equity of certain of the wholly owned subsidiaries that own or operate the collateral rig. We may redeem all or a portion of the 8.00% Senior Secured Notes at specified redemption prices.

Debt repayment, redemption, repurchases, tenders, and retirement

Scheduled maturities and installments—On the scheduled maturity date of December 15, 2025, we made a cash payment of $37 million to repay an equivalent aggregate principal amount of the outstanding 4.00% Exchangeable Bonds. On the scheduled maturity date of January 30, 2023, we made a cash payment of $49 million to repay an equivalent aggregate principal amount of the outstanding 0.50% exchangeable senior bonds due January 2023.

In the years ended December 31, 2025, 2024 and 2023, we made an aggregate cash payment of $480 million, $355 million and $262 million, respectively, to repay other indebtedness in scheduled installments.

Early retirement—During the three years ended December 31, 2025, we retired certain notes for which the aggregate principal amounts, cash payments and recognized gain or loss were as follows (in millions):


	2025						2024						2023
	Redeem or repurchase		Tender		Total		Redeem		Tender		Total		Redeem
5.375% Senior Secured Notes due May 2023	$	—	$	—	$	—	$	—	$	—	$	—	$	243
5.875% Senior Secured Notes due January 2024		—		—		—		—		—		—		311
7.75% Senior Secured Notes due October 2024		—		—		—		—		—		—		240
6.25% Senior Secured Notes due December 2024		—		—		—		—		—		—		250
6.125% Senior Secured Notes due August 2025		—		—		—		—		—		—		336
7.25% Senior Notes due November 2025		—		—		—		105		249		354		—
7.50% Senior Notes due January 2026		—		—		—		569		—		569		—
11.50% Senior Guaranteed Notes due January 2027		—		—		—		91		596		687		—
8.00% Senior Notes due February 2027		655		—		655		87		—		87		—
6.875% Senior Secured Notes due February 2027		248		—		248		—		—		—		—
7.00% Notes due June 2028		36		16		52		—		—		—		—
7.35% Senior Notes due December 2041		1		89		90		—		—		—		—
Aggregate principal amount of debt retired	$	940	$	105	$	1,045	$	852	$	845	$	1,697	$	1,380

Aggregate cash payment	$	939	$	100	$	1,039	$	862	$	886	$	1,748	$	1,402
Aggregate net gain (loss)	$	(1)	$	4	$	3	$	17	$	144	$	161	$	(32)

Additionally, in the year ended December 31, 2023, we recognized a net gain of $1 million associated with the retirement of $41 million aggregate principal amount of 4.625% Exchangeable Bonds exchanged by holders in October 2023.

- Definition

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-8A

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S50
-Paragraph 1
-Publisher FASB
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+ Details

CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Operating revenues
Contract drilling revenues	$ 3,965	$ 3,524	$ 2,832
Revenue from Contract with Customer, Product and Service [Extensible Enumeration]	us-gaap:OilAndGasServiceMember	us-gaap:OilAndGasServiceMember	us-gaap:OilAndGasServiceMember
Costs and expenses
Operating and maintenance	$ 2,406	$ 2,199	$ 1,986
Cost, Product and Service [Extensible Enumeration]	us-gaap:OilAndGasServiceMember	us-gaap:OilAndGasServiceMember	us-gaap:OilAndGasServiceMember
Depreciation and amortization	$ 659	$ 739	$ 744
General and administrative	195	214	187
Total costs and expenses	3,260	3,152	2,917
Loss on impairment of assets	(3,049)	(772)	(57)
Gain (loss) on disposal of assets, net	7	(17)	(183)
Operating loss	(2,337)	(417)	(325)
Other income (expense), net
Interest income	40	50	52
Interest expense, net of amounts capitalized	(555)	(362)	(646)
Gain (loss) on retirement of debt	3	161	(31)
Other, net	(99)	45	9
Total other income (expense), net	(611)	(106)	(616)
Loss before income taxes	(2,948)	(523)	(941)
Income tax expense (benefit)	(33)	(11)	13
Net loss	(2,915)	(512)	(954)
Net loss attributable to controlling interest	$ (2,915)	$ (512)	$ (954)
Loss per share, basic (in dollars per share)	$ (3.04)	$ (0.6)	$ (1.24)
Loss per share, diluted (in dollars per share)	$ (3.04)	$ (0.76)	$ (1.24)
Weighted-average shares outstanding, basic (in shares)	960	850	768
Weighted-average shares outstanding, diluted (in shares)	960	925	768

Debt (Repayment, Redemption, and retirement) (Details) - USD ($) $ in Millions			12 Months Ended
	Dec. 15, 2025	Jan. 30, 2023	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	Jun. 30, 2024	Oct. 31, 2023
Debt
Repayments of debt			$ 1,556	$ 2,103	$ 1,717
Aggregate principal amount of debt retired			1,045	1,697
Aggregate cash payment			1,039	1,748
Aggregate net gain (loss)			$ 3	$ 161	$ (31)
0.50% Exchangeable Senior Bonds due January 2023
Debt
Repayments of debt		$ 49
Debt instrument interest rate stated percentage		0.50%
4.00% Exchangeable Senior Bonds due December 2025
Debt
Repayments of debt	$ 37
Debt instrument interest rate stated percentage	4.00%
5.375% Senior Secured Notes due May 2023
Debt
Debt instrument interest rate stated percentage					5.375%
5.875% Senior Secured Notes due January 2024
Debt
Debt instrument interest rate stated percentage					5.875%
7.75% Senior Secured Notes due October 2024
Debt
Debt instrument interest rate stated percentage					7.75%
6.25% Senior Secured Notes due December 2024
Debt
Debt instrument interest rate stated percentage					6.25%
6.125% Senior Secured Notes due August 2025
Debt
Debt instrument interest rate stated percentage					6.125%
7.25% Senior Notes due November 2025
Debt
Debt instrument interest rate stated percentage				7.25%
Aggregate principal amount of debt retired				$ 354
7.50% Senior Notes due January 2026
Debt
Debt instrument interest rate stated percentage				7.50%
Aggregate principal amount of debt retired				$ 569
11.50% Senior Guaranteed Notes due January 2027
Debt
Debt instrument interest rate stated percentage				11.50%
Aggregate principal amount of debt retired				$ 687
8.00% Senior Notes due February 2027
Debt
Debt instrument interest rate stated percentage			8.00%	8.00%		8.00%
Aggregate principal amount of debt retired			$ 655	$ 87
6.875% Senior Secured Notes due February 2027
Debt
Debt instrument interest rate stated percentage			6.875%
Aggregate principal amount of debt retired			$ 248
7.00% Notes due June 2028
Debt
Debt instrument interest rate stated percentage			7.00%
Aggregate principal amount of debt retired			$ 52
7.35% Senior Notes due December 2041
Debt
Debt instrument interest rate stated percentage			7.35%
Aggregate principal amount of debt retired			$ 90
Aggregate of unspecified debt
Debt
Repayments of debt			$ 480	355	$ 262
4.625% Senior Guaranteed Exchangeable Bonds due September 2029
Debt
Debt instrument interest rate stated percentage			4.625%		4.625%		4.625%
Aggregate principal amount of debt retired					$ 41
Aggregate net gain (loss)					1
Redeem
Debt
Aggregate principal amount of debt retired			$ 940	852	1,380
Aggregate cash payment			939	862	1,402
Aggregate net gain (loss)			(1)	17	(32)
Redeem \| 5.375% Senior Secured Notes due May 2023
Debt
Aggregate principal amount of debt retired					243
Redeem \| 5.875% Senior Secured Notes due January 2024
Debt
Aggregate principal amount of debt retired					311
Redeem \| 7.75% Senior Secured Notes due October 2024
Debt
Aggregate principal amount of debt retired					240
Redeem \| 6.25% Senior Secured Notes due December 2024
Debt
Aggregate principal amount of debt retired					250
Redeem \| 6.125% Senior Secured Notes due August 2025
Debt
Aggregate principal amount of debt retired					$ 336
Redeem \| 7.25% Senior Notes due November 2025
Debt
Aggregate principal amount of debt retired				105
Redeem \| 7.50% Senior Notes due January 2026
Debt
Aggregate principal amount of debt retired				569
Redeem \| 11.50% Senior Guaranteed Notes due January 2027
Debt
Aggregate principal amount of debt retired				91
Redeem \| 8.00% Senior Notes due February 2027
Debt
Aggregate principal amount of debt retired			655	87
Redeem \| 6.875% Senior Secured Notes due February 2027
Debt
Aggregate principal amount of debt retired			248
Redeem \| 7.00% Notes due June 2028
Debt
Aggregate principal amount of debt retired			36
Redeem \| 7.35% Senior Notes due December 2041
Debt
Aggregate principal amount of debt retired			1
Tender
Debt
Aggregate principal amount of debt retired			105	845
Aggregate cash payment			100	886
Aggregate net gain (loss)			4	144
Tender \| 7.25% Senior Notes due November 2025
Debt
Aggregate principal amount of debt retired				249
Tender \| 11.50% Senior Guaranteed Notes due January 2027
Debt
Aggregate principal amount of debt retired				$ 596
Tender \| 7.00% Notes due June 2028
Debt
Aggregate principal amount of debt retired			16
Tender \| 7.35% Senior Notes due December 2041
Debt
Aggregate principal amount of debt retired			$ 89

Revenues (Disaggregation) (Details) - USD ($) $ in Millions	12 Months Ended
Revenues (Disaggregation) (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Revenue
Contract drilling revenues	$ 3,965	$ 3,524	$ 2,832
U.S.
Revenue
Contract drilling revenues	1,635	1,566	1,433
Brazil
Revenue
Contract drilling revenues	872	727	298
Norway
Revenue
Contract drilling revenues	639	654	603
Other Countries
Revenue
Contract drilling revenues	819	577	498
Ultra-deepwater floaters
Revenue
Contract drilling revenues	2,777	2,518	2,072
Ultra-deepwater floaters \| U.S.
Revenue
Contract drilling revenues	1,635	1,566	1,433
Ultra-deepwater floaters \| Brazil
Revenue
Contract drilling revenues	872	727	298
Ultra-deepwater floaters \| Other Countries
Revenue
Contract drilling revenues	270	225	341
Harsh environment floaters
Revenue
Contract drilling revenues	1,188	1,006	760
Harsh environment floaters \| Norway
Revenue
Contract drilling revenues	639	654	603
Harsh environment floaters \| Other Countries
Revenue
Contract drilling revenues	$ 549	$ 352	$ 157

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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+ Details

Long-Lived Assets (Acquisitions) (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024	Jun. 30, 2024	Sep. 30, 2023
Acquisition
Property and equipment, net	$ 12,577	$ 15,831
Cash and cash equivalents	620	560
Accounts receivable	540	564
Accounts payable	$ 242	$ 255
Orion/Transocean Norge
Acquisition
Property and equipment, net			$ 517
Cash and cash equivalents			5
Accounts receivable			$ 4
Liquila/Deepwater Aquila
Acquisition
Property and equipment, net				$ 126
Cash and cash equivalents				7
Accounts payable				$ 19

Income Taxes (Reconciliation) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Income tax benefit reconciliation
Federal statutory tax rate	$ (220)	$ (40)	$ (74)
Cantonal taxes	$ (13)
Effective Income Tax Rate Reconciliation, State and Local Jurisdiction, Contribution Greater than 50 Percent, Tax Effect [Extensible Enumeration]	rig:ZgMember
Changes in valuation allowance		208	(23)
Tax rate differential		74	129
Changes due to operational restructuring		(452)
Changes in unrecognized tax benefits, net	$ (123)	(4)	(37)
Tax attribute expirations		185
Deemed profits taxes		12	11
Withholding taxes		4	5
Other, net		2	2
Income tax expense (benefit)	$ (33)	$ (11)	$ 13
Tax Jurisdiction of Domicile [Extensible Enumeration]	Switzerland	Switzerland	Switzerland
Income tax reconciliation, percent
Federal statutory rate (as a percent)	7.48%	7.83%	7.83%
Cantonal taxes (as a percent)	0.44%
Changes in unrecognized tax benefits (as a percent)	4.18%
Effective tax rate (as a percent)	1.13%	2.20%	(1.40%)
LUXEMBOURG
Income tax reconciliation, percent
Tax effect of foreign net operating losses		$ 280	$ 8
Switzerland (Domicile)
Income tax benefit reconciliation
Income tax expense (benefit)	$ (21)
Switzerland
Income tax benefit reconciliation
Changes in valuation allowance	131
Changes due to operational restructuring	(13)
Other, net	$ 12
Income tax reconciliation, percent
Changes in valuation allowance (as a percent)	(4.46%)
Changes due to operational restructuring (as a percent)	0.44%
Other, net (as a percent)	(0.40%)
Foreign
Income tax benefit reconciliation
Other, net	$ 9
Income tax expense (benefit)	$ 1
Income tax reconciliation, percent
Other, net (as a percent)	(0.30%)
Bermuda
Income tax benefit reconciliation
Changes in valuation allowance	$ 212
Tax rate differential	(107)
Other, net	$ 13
Income tax reconciliation, percent
Changes in valuation allowance (as a percent)	(7.21%)
Tax rate differential (as a percent)	3.64%
Other, net (as a percent)	(0.42%)
U.S.
Income tax benefit reconciliation
Changes in valuation allowance	$ 20
Tax rate differential	65
Other, net	$ (15)
Income tax reconciliation, percent
Changes in valuation allowance (as a percent)	(0.68%)
Tax rate differential (as a percent)	(2.21%)
Other, net (as a percent)	0.51%
LUXEMBOURG
Income tax benefit reconciliation
Changes in valuation allowance	$ (20)
Changes due to operational restructuring	43
Other, net	$ 8
Income tax reconciliation, percent
Changes in valuation allowance (as a percent)	0.68%
Changes due to operational restructuring (as a percent)	(1.46%)
Other, net (as a percent)	(0.27%)
Norway
Income tax benefit reconciliation
Changes in currency exchange	$ (17)
Other, net	$ 24
Income tax reconciliation, percent
Changes in currency exchange (as a percent)	0.56%
Other, net (as a percent)	(0.82%)
Hungary
Income tax benefit reconciliation
Changes in valuation allowance	$ 26
Changes in currency exchange	(25)
Other, net	$ 1
Income tax reconciliation, percent
Changes in valuation allowance (as a percent)	(0.88%)
Changes in currency exchange (as a percent)	0.85%
Other, net (as a percent)	(0.02%)
Brazil
Income tax benefit reconciliation
Tax rate differential	$ 16
Other, net	$ (19)
Income tax reconciliation, percent
Tax rate differential (as a percent)	(0.54%)
Other, net (as a percent)	0.65%
U.K.
Income tax benefit reconciliation
Changes in valuation allowance	$ (36)
Other, net	$ (5)
Income tax reconciliation, percent
Changes in valuation allowance (as a percent)	1.22%
Other, net (as a percent)	0.15%

Significant Accounting Policies (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Functional currency
Net foreign currency exchange gain (loss)	$ (13)	$ 16	$ 10
Materials and supplies
Materials and supplies, allowance for obsolescence	$ 140	$ 178
Property and equipment
Property and equipment as a percentage of total assets	80.00%
Drilling rig units
Property and equipment
Estimated original useful life	35 years
Buildings and improvements \| Minimum
Property and equipment
Estimated original useful life	3 years
Buildings and improvements \| Maximum
Property and equipment
Estimated original useful life	30 years
Machinery and equipment \| Minimum
Property and equipment
Estimated original useful life	4 years
Machinery and equipment \| Maximum
Property and equipment
Estimated original useful life	20 years

Revenues

12 Months Ended

Dec. 31, 2025

Revenues.

Revenues

Note 5—Revenues

Overview—We earn revenues primarily by performing the following activities: (i) providing our drilling rig, together with the work crews, related equipment and services necessary to operate the rig, (ii) providing certain pre-operating activities, including rig preparation and equipment modifications required for the contract, and (iii) delivering the drilling rig by mobilizing to and demobilizing from the drill location. For most of our contracts with customers, our drilling services represent a single performance obligation that is satisfied over time, the duration of which varies by contract. As of December 31, 2025, the drilling contract with the longest expected remaining duration, excluding unexercised options, extends through May 2030.

Disaggregation—Our contract drilling revenues, disaggregated by asset group and by country in which they were earned, were as follows (in millions):


	Year ended December 31, 2025						Year ended December 31, 2024						Year ended December 31, 2023
	Ultra-		Harsh				Ultra-		Harsh				Ultra-		Harsh
	deepwater		environment				deepwater		environment				deepwater		environment
	floaters		floaters		Total		floaters		floaters		Total		floaters		floaters		Total
U.S.	$	1,635	$	—	$	1,635	$	1,566	$	—	$	1,566	$	1,433	$	—	$	1,433
Brazil		872		—		872		727		—		727		298		—		298
Norway		—		639		639		—		654		654		—		603		603
Other countries (a)		270		549		819		225		352		577		341		157		498
Total contract drilling revenues	$	2,777	$	1,188	$	3,965	$	2,518	$	1,006	$	3,524	$	2,072	$	760	$	2,832

(a)	The aggregate contract drilling revenues earned in other countries that individually represented less than 10 percent of total contract drilling revenues.

Major customers—For the year ended December 31, 2025, Petróleo Brasileiro S.A. (together with its affiliates, “Petrobras”), Shell plc (together with its affiliates, “Shell”), and Equinor ASA (together with its affiliates, “Equinor”) represented 22 percent, 22 percent and 12 percent, respectively, of our consolidated operating revenues. For the year ended December 31, 2024, Shell, Petrobras and Equinor represented 27 percent, 21 percent and 13 percent, respectively, of our consolidated operating revenues. For the year ended December 31, 2023, Shell, Equinor, TotalEnergies SE and Petrobras represented 27 percent, 16 percent, 12 percent and 11 percent, respectively, of our consolidated operating revenues.

Contract liabilities—Contract liabilities for our contracts with customers were as follows (in millions):


		December 31,
		2025			2024
Deferred contract revenues, recorded in other current liabilities		$	181		$	231
Deferred contract revenues, recorded in other long-term liabilities			92			212
Total contract liabilities		$	273		$	443

Significant changes in contract liabilities were as follows (in millions):


		Years ended December 31,
		2025			2024
Total contract liabilities, beginning of period		$	443		$	398
Decrease due to recognition of revenues for goods and services			(260)			(243)
Increase due to goods and services transferred over time			90			288
Total contract liabilities, end of period		$	273		$	443

Pre-operating costs—In the years ended December 31, 2025, 2024 and 2023, we recognized pre-operating costs of $158 million, $138 million and $69 million, respectively, recorded in operating and maintenance costs. Recognition increased in each of the two years in the period ended December 31, 2025, primarily as a result of the commencement of operations for one rig that mobilized to Brazil, two rigs that mobilized to Australia, one rig that mobilized to Romania and one rig that we reactivated for a contract in Brazil in the years ended December 31, 2024 and 2023. At December 31, 2025 and 2024, the carrying amount of our unrecognized pre-operating costs to obtain contracts was $136 million and $224 million, respectively, recorded in other assets.

- Definition

The entire disclosure of revenue from contract with customer to transfer good or service and to transfer nonfinancial asset. Includes, but is not limited to, disaggregation of revenue, credit loss recognized from contract with customer, judgment and change in judgment related to contract with customer, and asset recognized from cost incurred to obtain or fulfill contract with customer. Excludes insurance and lease contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-7

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-9

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-10

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 15
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-15

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-12

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-12

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-12

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-12

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-12

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-13

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Topic 606
-Publisher FASB
-URI https://asc.fasb.org/606/tableOfContent

+ Details

Significant Accounting Policies

12 Months Ended

Dec. 31, 2025

Significant Accounting Policies

Significant Accounting Policies

Note 2—Significant Accounting Policies

Accounting estimates—To prepare financial statements in accordance with accounting principles generally accepted in the United States (“U.S.”), we must make judgments by applying estimates and assumptions that affect the reported amounts of assets, liabilities, revenues and expenses and the disclosures of contingent assets and liabilities. On an ongoing basis, we evaluate our estimates and assumptions, including those related to our income taxes, property and equipment, equity investments, contingencies, allowance for excess materials and supplies, assets held for sale, postemployment benefit plans and share-based compensation. We base our estimates and assumptions on historical experience and other factors that we believe are reasonable. Actual results could differ from such estimates.

Fair value measurements—We estimate fair value at an exchange price that would be received to sell an asset or paid to transfer a liability in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants. Our valuation techniques require inputs that we categorize using a three-level hierarchy, from highest to lowest level of observable inputs, as follows: (1) significant observable inputs, including unadjusted quoted prices for identical assets or liabilities in active markets (“Level 1”), (2) significant other observable inputs, including direct or indirect market data for similar assets or liabilities in active markets or identical assets or liabilities in less active markets (“Level 2”) and (3) significant unobservable inputs, including those that require considerable judgment for which there is little or no market data (“Level 3”). When a valuation requires multiple input levels, we categorize the entire fair value measurement according to the lowest level of input that is significant to the measurement even though we may have also utilized significant inputs that are more readily observable.

Consolidation—We consolidate entities in which we have a majority voting interest and entities that meet the criteria for variable interest entities for which we are deemed to be the primary beneficiary for accounting purposes. We eliminate intercompany transactions and accounts in consolidation. We apply the equity method of accounting for an equity investment in an unconsolidated entity if we have the ability to exercise significant influence over the entity that (a) does not meet the variable interest entity criteria or (b) meets the variable interest entity criteria, but for which we are not deemed to be the primary beneficiary. We measure other equity investments at fair value if the investment has a fair value that is readily determinable; otherwise, we measure the investment at cost, less any impairment. We separately present within equity on our consolidated balance sheets the ownership interests attributable to parties with noncontrolling interests in our consolidated subsidiaries, and we separately present net income attributable to such parties on our consolidated statements of operations. See Note 4—Unconsolidated Affiliates and Note 13—Equity.

Functional currency—We consider the U.S. dollar to be the functional currency for all of our operations since the majority of our revenues and expenditures are denominated in U.S. dollars. Consequently, our exposure to currency exchange rate fluctuations is limited.

We recognize currency exchange rate gains and losses in other, net. In the years ended December 31, 2025, 2024 and 2023, we recognized a net loss of $13 million, a net gain of $16 million and a net gain of $10 million, respectively, related to currency exchange rates.

Revenues and related pre-operating costs—We recognize revenues earned under our drilling contracts based on variable dayrates, which range from a full operating dayrate to lower rates or zero rates for periods when drilling operations are interrupted or restricted, based on the specific activities we perform during the contract on an hourly, or more frequent, basis. Such dayrate consideration is attributed to the distinct time period to which it relates within the contract term, and therefore, is recognized as we perform the services. When the operating dayrate declines over the contract term, we recognize revenues on a straight-line basis over the estimated contract period. We recognize reimbursement revenues and the corresponding costs as we provide the customer-requested goods and services, when such reimbursable costs are incurred while performing drilling operations. Prior to performing drilling operations, we may receive pre-operating revenues, on either a fixed lump-sum or variable dayrate basis, for mobilization, contract preparation, customer-requested goods and services or capital upgrades, for which we record a contract liability and recognize as revenues on a straight-line basis over the estimated contract period. We recognize losses for loss contracts as such losses are incurred. We recognize revenues for demobilization over the contract period unless otherwise constrained. We recognize revenues from contract terminations as we fulfill our obligations and all contingencies have been resolved. We apply the optional exemption that permits us to exclude disclosure of the estimated transaction price related to the variable portion of unsatisfied performance obligations at the end of the reporting period, as our transaction price is typically based on a single performance obligation consisting of a series of distinct hourly, or more frequent, periods, the variability of which will be resolved at the time of the future services.

To obtain contracts with our customers, we incur pre-operating costs to prepare a rig for contract and mobilize a rig to the drilling location. We defer such pre-operating contract preparation and mobilization costs for recognition in operating and maintenance costs over the estimated contract period on a straight-line basis, consistent with the general pace of activity. See Note 5—Revenues.

Income taxes—We provide for income taxes based on expected taxable income, statutory rates and tax laws in the jurisdictions in which we operate or have a taxable presence. We recognize the effect of changes in tax laws as of the date of enactment. We recognize potential global intangible low-taxed income inclusions as a period cost.

We establish liabilities for estimated tax exposures, and we recognize the provisions and benefits resulting from changes to those liabilities, together with related interest and penalties, in income tax expense or benefit. Income tax exposure items include potential challenges to permanent establishment positions, intercompany pricing, disposition transactions, and withholding tax rates and their applicability. Such tax exposures may be affected by changes in applicable tax law or other factors, which could cause us to revise our prior estimates, and are generally resolved through the settlement of audits within the tax jurisdictions or by judicial means.

We measure deferred tax assets and liabilities using enacted tax rates that will apply in the years in which the deferred tax assets and liabilities are expected to be recovered or paid. To evaluate our ability to realize deferred tax assets, we consider all available positive and negative evidence, including projected future taxable income and the existence of cumulative losses in recent years. We record a valuation allowance for deferred tax assets when it is more likely than not that some or all of the benefit from the deferred tax asset will not be realized. For example, we may record a valuation allowance for deferred tax assets resulting from net operating losses incurred during the year in certain jurisdictions for which the benefit of the losses will not be realized or for foreign tax credit carryforwards that may expire prior to their utilization. See Note 10—Income Taxes.

Cash and cash equivalents—We consider cash equivalents to include highly liquid debt instruments with original maturities of three months or less, such as time deposits with commercial banks that have high credit ratings, U.S. Treasury and government securities, Eurodollar time deposits, certificates of deposit and commercial paper. We may also invest excess funds in no-load, open-ended, management investment trusts. Such management trusts invest exclusively in high-quality money market instruments.

Restricted cash and cash equivalents—We maintain restricted cash and cash equivalents that are either pledged for debt service under certain bond indentures, as required under certain bank credit arrangements, or held in accounts that are subject to restrictions due to legislation, regulation or court order. We classify such restricted cash and cash equivalents in current assets if the restriction is expected to expire or otherwise be resolved within one year or if such funds are considered to correspond to liabilities that are properly classified as current liabilities. See Note 8—Debt.

Materials and supplies—We record materials and supplies at their average cost less an allowance for excess items. We estimate the allowance for excess items based on historical experience and expectations for future use of the materials and supplies. At December 31, 2025 and 2024, our allowance for excess items was $140 million and $178 million, respectively. The decrease was primarily due to the disposal of materials and supplies associated with rigs and related assets sold or classified as held for sale.

Assets held for sale—We classify an asset as held for sale when the facts and circumstances meet the criteria for such classification, including the following: (a) we have committed to a plan to sell the asset, (b) the asset is available for immediate sale, (c) we have initiated actions to complete the sale, including locating a buyer, (d) the sale is expected to be completed within one year, (e) the asset is being actively marketed at a price that is reasonable relative to its fair value, and (f) the plan to sell is unlikely to be subject to significant changes or termination. The carrying amount of our assets held for sale is measured at the lower of its carrying amount or fair value less

cost to sell. We consider a held-for-sale asset to be impaired to the extent its carrying amount exceeds its estimated fair value less cost to sell. See Note 6—Long-Lived Assets.

Property and equipment—We apply judgment to account for our property and equipment, consisting primarily of offshore drilling rigs and related equipment, related to estimates and assumptions for cost capitalization, useful lives and salvage values. We base our estimates and assumptions on historical experience and expectations regarding future industry conditions and operations. At December 31, 2025, the aggregate carrying amount of our property and equipment represented 80 percent of our total assets.

We capitalize expenditures for newbuilds, renewals, replacements and improvements, including capitalized interest, if applicable, and we recognize the expense for maintenance and repair costs as incurred. For newbuild construction projects, we also capitalize the initial preparation, mobilization and commissioning costs incurred until the drilling unit is placed into service. Upon sale or other disposition of an asset, we recognize a net gain or loss on disposal of the asset, which is measured as the difference between the net carrying amount of the asset and the net proceeds received. We compute depreciation using the straight-line method after allowing for salvage values.

The estimated original useful life of our drilling units is 35 years, our buildings and improvements range from three to 30 years and our machinery and equipment range from four to 20 years. We reevaluate the remaining useful lives and salvage values of our rigs when certain events occur that directly impact the useful lives and salvage values of the rigs, including changes in operating condition, functional capability and market and economic factors. When evaluating the remaining useful lives of rigs, we also consider major capital upgrades required to perform certain contracts and the long-term impact of those upgrades on future marketability.

Long-lived asset impairment—We review the carrying amounts of long-lived assets, including property and equipment and right-of-use assets, for potential impairment when events occur or circumstances change that indicate that the carrying amount of such assets may not be recoverable. For assets classified as held and used, we determine recoverability by evaluating the estimated undiscounted future net cash flows based on projected dayrates and utilization of the asset group under review. We consider our asset groups to be ultra-deepwater floaters and harsh environment floaters. When an impairment of an asset group is indicated, we measure an impairment as the amount by which the carrying amount of the asset group exceeds its estimated fair value. We estimate the fair value of an asset group by applying a variety of valuation methods, incorporating a combination of income, market and cost approaches, using projected discounted cash flows and estimates of the exchange price that would be received for the assets in the principal or most advantageous market for the assets in an orderly transaction between market participants as of the measurement date. See Note 6—LongLived Assets.

Equity investments and impairment—We review our equity-method investments, and other equity investments for which a readily determinable fair value is not available, for potential impairment when events or changes in circumstances indicate that the carrying amount of the investment might not be recoverable in the near term. If we determine that an impairment that is other than temporary exists, we recognize an impairment loss, measured as the amount by which the carrying amount of the investment exceeds its estimated fair value. To estimate the fair value of the investment, we apply valuation methods that rely primarily on the income and market approaches. We amortize the basis difference caused by such impairments using the straight-line method over the estimated life of the asset. See Note 4—Unconsolidated Affiliates.

Pension and other postemployment benefit plans—We use a measurement date of January 1 to determine net periodic benefit costs and December 31 to determine plan benefit obligations and the fair values of plan assets. We determine our net periodic benefit costs based on a market-related value of assets that reduces year-to-year volatility by including investment gains or losses subject to amortization over a five-year period from the year in which they occur. We calculate investment gains or losses for this purpose as the difference between the expected return calculated using the market-related value of assets and the actual return based on the market-related value of assets. If gains or losses exceed 10 percent of the greater of plan assets or plan liabilities, we amortize such gains or losses over the average expected future lifetime of the participants.

We measure the actuarially determined obligations and related costs for our defined benefit pension and other postemployment benefit plans, retiree life insurance and medical benefits, by applying assumptions, the most significant of which include long-term rate of return on plan assets, discount rates and mortality rates. For the long-term rate of return, we develop our assumptions regarding the expected rate of return on plan assets based on projected long-term investment returns, and we weight the assumptions based on each plan’s asset allocation. For the discount rate, we base our assumptions on a yield curve approach using Aa-rated corporate bonds and the expected timing of future benefit payments. At December 31, 2025 and 2024, the funded status of our pension and other postemployment benefit plans represented an aggregate liability of $105 million and $104 million, respectively, and an aggregate asset of $78 million and $73 million, respectively. See Note 9—Benefit Plans.

Share-based compensation—To measure the fair values of granted or modified service-based restricted share units, we use the market price of our shares on the grant date or modification date. To measure the fair values of granted or modified performance-based restricted share units subject to market factors, we use an average price at the performance start date and project performance based on a Monte Carlo simulation model under a risk-neutral approach and apply assumptions for the expected life, risk-free interest rate, expected volatility and dividend yield. To measure the fair values of granted or modified performance-based restricted share units that are subject to performance targets, we use the market price of our shares on the grant date or modification date and adjust the value for the projected performance rate expected to be achieved at the end of the measurement period. We recognize share-based compensation expense in the

same financial statement line item as cash compensation paid to the respective employees or non-employee directors. We recognize such compensation expense on a straight-line basis over the service period through the date the employee or non-employee director is no longer required to provide service to earn the award. See Note 14—ShareBased Compensation.

Contingencies—We assess our contingencies on an ongoing basis to evaluate the appropriateness of our liabilities and disclosures for such contingencies. We establish liabilities for estimated loss contingencies when we believe a loss is probable and the amount of the probable loss can be reasonably estimated. Once established, we adjust the carrying amount of a contingent liability upon the occurrence of a recognizable event when facts and circumstances change, altering our previous assumptions with respect to the likelihood or amount of loss. We recognize corresponding assets for those loss contingencies that we believe are probable of being recovered through insurance. We recognize expense for legal costs as they are incurred, and we recognize a corresponding asset for such legal costs only if we expect such legal costs to be recovered through insurance.

Income Taxes (Tax Provision and Rate) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Effective Income Tax Rate Reconciliation [Line Items]
Loss before income tax benefit	$ 2,948	$ 523	$ 941
Effective tax rate (as a percent)	1.13%	2.20%	(1.40%)
Components of provision (benefit) for income taxes
Current tax expense (benefit)	$ 78	$ 31	$ (5)
Deferred tax expense (benefit)	(111)	(42)	18
Income tax expense (benefit)	(33)	$ (11)	$ 13
Switzerland (Domicile)
Effective Income Tax Rate Reconciliation [Line Items]
Loss before income tax benefit	2,010
Components of provision (benefit) for income taxes
Income tax expense (benefit)	(21)
Switzerland cantons
Components of provision (benefit) for income taxes
Income tax expense (benefit)	(13)
Non-Switzerland
Effective Income Tax Rate Reconciliation [Line Items]
Loss before income tax benefit	937
Components of provision (benefit) for income taxes
Income tax expense (benefit)	$ 1

Share-Based Compensation

12 Months Ended

Dec. 31, 2025

Share-Based Compensation

Share-Based Compensation

Note 14—Share-Based Compensation

Overview

We have a long-term incentive plan (the “Long-Term Incentive Plan”) for executives, key employees and non-employee directors under which awards can be granted in the form of restricted share units, restricted shares, stock options, stock appreciation rights and cash performance awards. Awards may be granted as service awards that are earned over a defined service period or as performance awards that are earned based on the achievement of certain market factors or performance targets or a combination of market factors and performance targets. The compensation committee of our board of directors determines the terms and conditions of the awards granted under the Long-Term Incentive Plan. At December 31, 2025, we had 154.2 million shares authorized and 37.3 million shares available to be granted under the Long-Term Incentive Plan. At December 31, 2025, the total unrecognized compensation cost related to our unvested share-based awards was $33 million, which we expect to recognize over a weighted-average period of 1.7 years.

Service awards typically vest either in three equal annual installments beginning on the first anniversary date of the grant or in an aggregate installment at the end of the stated vesting period. Service-based stock options, once fully vested, are typically exercisable during a seven-year period. Performance awards are typically subject to a three-year measurement period and typically vest in one aggregate installment following the ultimate determination date.

Service awards

Restricted share units—A restricted share unit subject to service requirements is a notional unit that is equivalent to one share but has no voting rights until the underlying share is issued. The following table summarizes unvested activity during the year ended December 31, 2025 for service-based units granted under our incentive plan:


		Number		Weighted-average
		of		grant-date fair value
		units		per unit
Unvested at January 1, 2025		7,659,028		$	5.44
Granted		6,852,828			3.47
Vested		(5,280,936)			4.72
Forfeited		(113,268)			4.46
Unvested at December 31, 2025		9,117,652		$	4.23

In the year ended December 31, 2025, the service-based units that vested had an aggregate grant-date fair value of $25 million. In the years ended December 31, 2024 and 2023, we granted 5,116,762 and 3,744,049 service-based units, respectively, with a per unit weighted-average grant-date fair value of $5.29 and $7.23, respectively. In the years ended December 31, 2024 and 2023, we had 6,727,943 and 6,200,155 service-based units, respectively, that vested with an aggregate grant-date fair value of $32 million and $18 million, respectively.

Stock options—The following table summarizes activity during the year ended December 31, 2025 for vested service-based stock options outstanding under our incentive plan:


							Weighted-average
		Number		Weighted-average			remaining		Aggregate
		of shares		exercise price			contractual term		intrinsic value
		under option		per share			(years)		(in millions)
Outstanding at January 1, 2025		4,069,334		$	9.53		2.93		$	—
Forfeited		(17,006)			8.35
Outstanding at December 31, 2025		4,052,328		$	9.54		1.92		$	—

Vested and exercisable at December 31, 2025		4,052,328		$	9.54		1.92		$	—

At December 31, 2025, 2024 and 2023, there were no outstanding unvested stock options to purchase our shares.

Performance awards

Restricted share units—A restricted share unit subject to performance requirements is a notional unit for which the awarded number of shares to be issued per unit remains uncertain until quantified as of the ultimate determination date following completion of the performance period. The following table summarizes unvested activity during the year ended December 31, 2025 for performance-based units under our incentive plan:


		Number		Weighted-average
		of		grant-date fair value
		units		per unit
Unvested at January 1, 2025		3,495,925		$	5.78
Granted		3,138,657			3.35
Vested		(1,439,846)			6.74
Unvested at December 31, 2025		5,194,736		$	4.04

In the year ended December 31, 2025, the performance-based units that vested had an aggregate grant-date fair value of $10 million. In the years ended December 31, 2024 and 2023, we granted 2,687,268 and 1,912,292 performance-based units, respectively, with a per unit weighted-average grant-date fair value of $5.10 and $6.74, respectively. In the years ended December 31, 2024 and 2023 we had 4,429,028 and 3,025,512 performance-based units, respectively, that vested with an aggregate grant-date fair value of $21 million and $11 million, respectively.

Financial Instruments (Tables)

12 Months Ended

Dec. 31, 2025

Financial Instruments

Carrying amounts and fair values of the financial instruments

The carrying amounts and fair values of our financial instruments were as follows (in millions):


		December 31, 2025						December 31, 2024
		Carrying			Fair			Carrying			Fair
		amount			value			amount			value
Cash and cash equivalents		$	620		$	620		$	560		$	560
Restricted cash and cash equivalents			377			377			381			381
Total debt			5,657			5,755			6,881			6,888

Significant Accounting Policies (Pension and Other Postemployment Benefit Plans) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024
Pension and other postretirement benefits
Recognition period of investment gains or losses related to asset valuation for determining net periodic benefit cost	5 years
Conditional amortization gains or losses as percentage of greater of plan assets or liabilities, minimum	10.00%
Pension liability, current and noncurrent	$ 105	$ 104
Pension asset, non-current	$ 78	$ 73

- Definition

Amount of asset, recognized in statement of financial position, for overfunded defined benefit pension and other postretirement plans.

+ References + Details

Benefit Plans (Defined Contribution Plans) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Benefit Plans
Contribution expense	$ 62	$ 63	$ 58

Supplemental Cash Flow Information (Details) - USD ($) shares in Millions, $ in Millions	1 Months Ended				12 Months Ended
	Jun. 30, 2024	Sep. 30, 2023	Jul. 31, 2023	Apr. 30, 2023	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	Oct. 31, 2023
Changes in other operating assets and liabilities
Increase in accounts receivable					$ (30.0)	$ (94.0)	$ (99.0)
(Increase) decrease in other assets					7.0	(92.0)	(91.0)
Increase (decrease) in accounts payable and other current liabilities					(12.0)	(86.0)	144.0
Decrease in other long-term liabilities					(7.0)	(3.0)	(6.0)
Change in income taxes receivable / payable, net					17.0	(19.0)	(36.0)
Change in receivables from / payables to affiliates, net						9.0	(8.0)
Net change in operating assets and liabilities					(25.0)	(285.0)	(96.0)
Certain cash operating activities
Cash payments for interest					538.0	521.0	408.0
Noncash investing and financing activities
Capital additions accrued at end of period					20.0	23.0	36.0
Finance lease installments settled with credits issued to customer					$ 39.0	$ 40.0	$ 44.0
Shares issued in exchanges of exchangeable bonds					201.0		434.0
Shares issued upon conversion (in shares)					73.3		65.1
Number of warrants issued to subscribe					22.2	22.2
Orion/Transocean Norge
Noncash investing and financing activities
Exchange					$ 2.0		$ 37.0
4.50% Shipyard Loans due September 2027
Noncash investing and financing activities
Debt instrument interest rate stated percentage					4.50%
4.625% Senior Guaranteed Exchangeable Bonds due September 2029
Noncash investing and financing activities
Shares issued in exchanges of exchangeable bonds					75.3
Debt instrument interest rate stated percentage					4.625%		4.625%	4.625%
4.00% Senior Guaranteed Exchangeable Bonds due December 2025
Noncash investing and financing activities
Shares issued upon conversion (in shares)					73.3
Debt instrument interest rate stated percentage					4.00%		4.00%	4.00%
2.50% Senior Guaranteed Exchangeable Bonds due January 2027
Noncash investing and financing activities
Shares issued upon conversion (in shares)			4.0	34.6
Debt instrument interest rate stated percentage			2.50%				2.50%
8.00% Senior Notes due February 2027
Noncash investing and financing activities
Debt instrument interest rate stated percentage	8.00%				8.00%	8.00%
Liquila/Deepwater Aquila
Noncash investing and financing activities
Acquisition of outstanding ownership interests in exchange for shares		$ 99.0				$ 431.0	$ 99.0
Newly issued shares in asset acquisition (in shares)		11.9
Orion/Transocean Norge
Noncash investing and financing activities
Acquisition of outstanding ownership interests in exchange for shares	$ 297.0
Newly issued shares in asset acquisition (in shares)	55.5
Orion/Transocean Norge \| 8.00% Senior Notes due February 2027
Noncash investing and financing activities
Debt instrument face value	$ 130.0
Debt instrument interest rate stated percentage	8.00%

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Cash flows from operating activities
Net loss	$ (2,915.0)	$ (512.0)	$ (954.0)
Adjustments to reconcile to net cash provided by operating activities:
Amortization of contract intangible asset		4.0	52.0
Depreciation and amortization	659.0	739.0	744.0
Share-based compensation expense	35.0	47.0	40.0
Loss on impairment of assets	3,049.0	772.0	57.0
(Gain) loss on disposal of assets, net	(7.0)	17.0	183.0
Amortization of debt-related balances, net	48.0	53.0	51.0
(Gain) loss on adjustment to bifurcated compound exchange feature	(10.0)	(214.0)	127.0
(Gain) loss on retirement of debt	(3.0)	(161.0)	31.0
Loss on conversion of debt to equity	99.0		27.0
Loss on impairment of investment in unconsolidated affiliate		5.0	5.0
Deferred income tax expense (benefit)	(111.0)	(42.0)	18.0
Other, net	14.0	(19.0)	(1.0)
Changes in contract liabilities, net	(170.0)	45.0	70.0
Changes in deferred costs, net	86.0	(2.0)	(190.0)
Changes in other operating assets and liabilities, net	(25.0)	(285.0)	(96.0)
Net cash provided by operating activities	749.0	447.0	164.0
Cash flows from investing activities
Capital expenditures	(123.0)	(254.0)	(427.0)
Investment in loans to unconsolidated affiliates		(3.0)	(3.0)
Investment in equity of unconsolidated affiliate			(10.0)
Proceeds from disposal of assets, net of costs to sell	84.0	101.0	10.0
Proceeds from disposal of equity investment in unconsolidated affiliate	6.0
Cash acquired in acquisition of unconsolidated affiliates		5.0	7.0
Net cash used in investing activities	(33.0)	(151.0)	(423.0)
Cash flows from financing activities
Repayments of debt	(1,556.0)	(2,103.0)	(1,717.0)
Proceeds from issuance of debt, net of issue costs	492.0	1,770.0	1,983.0
Proceeds from issuance of shares, net of issue costs	421.0
Other, net	(17.0)	(17.0)	(3.0)
Net cash provided by (used in) financing activities	(660.0)	(350.0)	263.0
Net increase (decrease) in unrestricted and restricted cash and cash equivalents	56.0	(54.0)	4.0
Unrestricted and restricted cash and cash equivalents, beginning of period	941.0	995.0	991.0
Unrestricted and restricted cash and cash equivalents, end of period	$ 997.0	$ 941.0	$ 995.0

Cybersecurity Risk Management and Strategy Disclosure	12 Months Ended
Cybersecurity Risk Management and Strategy Disclosure	Dec. 31, 2025
Cybersecurity Risk Management, Strategy, and Governance [Line Items]
Cybersecurity Risk Management Processes for Assessing, Identifying, and Managing Threats [Text Block]	Our approach to managing cybersecurity risk and safeguarding information across our organization embeds data protection and cybersecurity risk management throughout our enterprise and daily operations. We maintain processes for identifying, assessing and managing material risks, including such risks from cybersecurity threats, and such processes are integrated into our overall risk management system. Our enterprise risk register inventories significant risks to our company, including significant cybersecurity risks, and we maintain a separate functional risk register, specifically focusing on potential cybersecurity risks. Within these risk registers, we record each identified risk, describe its likelihood of occurrence and assess its potential impact, including the materiality thereof. As part of this exercise, mitigating measures are planned and implemented into action as necessary. As an additional feature of our cybersecurity risk management process, we have engaged an external service provider to support our cybersecurity team by performing penetration tests and periodic external security evaluations. We undertake to align our cybersecurity program, which encompasses both enterprise security and operational security, with the standards of the National Institute of Standards and Technology Cybersecurity Framework. We maintain continuous cyber threat-detection systems and have established an incident response plan, which contains playbooks for addressing and recovering from potential material cyberattacks and breaches of data security. In addition to establishing security measures for vendors, we require onboarding orientation and periodic training for all employees and board members that focuses on cybersecurity and information management, and we conduct regular cybersecurity awareness campaigns.
Cybersecurity Risk Management Processes Integrated [Flag]	true
Cybersecurity Risk Management Processes Integrated [Text Block]	We maintain processes for identifying, assessing and managing material risks, including such risks from cybersecurity threats, and such processes are integrated into our overall risk management system
Cybersecurity Risk Management Third Party Engaged [Flag]	true
Cybersecurity Risk Third Party Oversight and Identification Processes [Flag]	true
Cybersecurity Risk Materially Affected or Reasonably Likely to Materially Affect Registrant [Flag]	false
Cybersecurity Risk Board of Directors Oversight [Text Block]	Our board of directors oversees our enterprise risk register and cybersecurity program, including related policies and procedures. As part of this oversight, the audit committee of our board of directors receives regular status reports and updates from our management team and conducts periodic executive sessions with our Vice President, Information Technology. Such status reports and executive sessions cover cybersecurity matters, such as developments to our program, key risk indicators, emerging risks, and identified incidents.
Cybersecurity Risk Board Committee or Subcommittee Responsible for Oversight [Text Block]	audit committee
Cybersecurity Risk Process for Informing Board Committee or Subcommittee Responsible for Oversight [Text Block]	As part of this oversight, the audit committee of our board of directors receives regular status reports and updates from our management team and conducts periodic executive sessions with our Vice President, Information Technology.
Cybersecurity Risk Role of Management [Text Block]	In addition, our Vice President, Information Technology, who has more than 20 years of industry experience and over 25 years of experience with the development, training and controls of effective global enterprise cybersecurity programs, oversees the implementation and compliance of our cybersecurity program and mitigation of information security related risks. Such oversight includes (i) reviewing our enterprise risk register, (ii) maintaining adequate processes to manage the identified risks under our cybersecurity program, (iii) regularly analyzing logs of cybersecurity threats and vulnerabilities and (iv) overseeing prevention, detection, mitigation and remediation efforts in general, including the development and maintenance of the above-mentioned incident response plan. Additionally, we maintain an experienced information technology team at the employee level that supports our Vice President, Information Technology in implementing our cybersecurity program and internal reporting, security and mitigation functions.
Cybersecurity Risk Management Positions or Committees Responsible [Flag]	true
Cybersecurity Risk Management Positions or Committees Responsible [Text Block]	the audit committee of our board of directors receives regular status reports and updates from our management team and conducts periodic executive sessions with our Vice President, Information Technology
Cybersecurity Risk Management Expertise of Management Responsible [Text Block]	Vice President, Information Technology, who has more than 20 years of industry experience and over 25 years of experience with the development, training and controls of effective global enterprise cybersecurity programs
Cybersecurity Risk Process for Informing Management or Committees Responsible [Text Block]	Such oversight includes (i) reviewing our enterprise risk register, (ii) maintaining adequate processes to manage the identified risks under our cybersecurity program, (iii) regularly analyzing logs of cybersecurity threats and vulnerabilities and (iv) overseeing prevention, detection, mitigation and remediation efforts in general, including the development and maintenance of the above-mentioned incident response plan.
Cybersecurity Risk Management Positions or Committees Responsible Report to Board [Flag]	true

Leases (Finance lease) (Details)	12 Months Ended
Leases (Finance lease) (Details)	Dec. 31, 2025 USD ($)
Leases
Implicit interest rate (as a percent)	7.80%
End of lease obligation	$ 1

Long-Lived Assets (Assets held for sale) (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Assets held for sale
Assets held for sale	$ 24	$ 343
Cash deposits received for the sale of assets	$ 3

Equity

12 Months Ended

Dec. 31, 2025

Equity

Equity

Note 13—Equity

Share issuance in public offering—In September 2025, we issued 143.8 million Transocean Ltd. shares in a public offering, including 4.0 million Transocean Ltd. shares issued to Perestroika. In connection with the issuance, we received $421 million aggregate cash proceeds, net of issue costs, including $12 million from Perestroika.

We maintain an at-the-market equity offering program (the “ATM Program”). We may use the net proceeds from our ongoing ATM Program for general corporate purposes, which may include, among other things, the repayment or refinancing of indebtedness and the funding of working capital, capital expenditures, investments and additional balance sheet liquidity. In June 2021, we entered into an equity distribution agreement with a sales agent for the offer and sale of our shares, with a maximum aggregate net offering price of up to $400 million, under the ATM Program. In August 2022, we entered into an equity distribution agreement with a sales agent for the offer and sale of our shares, with a maximum aggregate net offering price of up to $435 million, under the ATM Program. In the three years in the period ended December 31, 2025, we did not issue any shares under the ATM Program.

Share issuance in debt exchanges—In the year ended December 31, 2025, we issued 73.3 million Transocean Ltd. shares with an aggregate fair value of $201 million to certain holders that elected to exchange the 4.00% Exchangeable Bonds pursuant to the Exchange Agreements. In the year ended December 31, 2023, we issued 65.1 million shares with an aggregate fair value of $434 million to certain holders that elected to exchange the 2.50% Exchangeable Bonds, the 4.00% Exchangeable Bonds and the 4.625% Exchangeable Bonds under terms of the governing indentures. See Note 8—Debt.

Share issuance in acquisitions—In June 2024, we issued 55.5 million Transocean Ltd. shares with an aggregate fair value of $297 million as partial consideration to acquire the outstanding 67.0 percent ownership interest in Orion. In September 2023, we issued 11.9 million Transocean Ltd. shares with an aggregate fair value of $99 million to acquire the outstanding 80.0 percent ownership interests in Liquila. See Note 4—Unconsolidated Affiliates and Note 6—Long-Lived Assets.

Shares held by us—We and one of our subsidiaries hold Transocean Ltd. shares for future use to deliver shares in connection with sales under the ATM Program and in connection with awards granted under our incentive plans or other rights to acquire our shares. At December 31, 2025, we and our subsidiary held 82.9 million and 19.6 million shares, respectively, and at December 31, 2024, we and our subsidiary held 22.5 million and 42.5 million shares, respectively.

Share capital currency change—In May 2024, at our annual general meeting, shareholders approved (a) redenominating the currency of our share capital from Swiss francs to U.S. dollars and (b) reducing the par value of our shares for purposes of such redenomination. As a result of the redenomination and reduction, made effective as of January 1, 2024, the par value of each of our shares was changed to $0.10 from CHF 0.10.

Warrants—At December 31, 2025 and 2024, we had 22.2 million outstanding warrants to purchase Transocean Ltd. shares. The warrants may be exercised by holders at any time prior to the close of business on March 13, 2026 at an exercise price equal to $3.71 per share, subject to certain anti-dilutive adjustments, and at our election, such exercise may be settled by delivering cash, Transocean Ltd. shares or a combination of cash and shares. At December 31, 2025 and 2024, the carrying amount of the warrants, recorded as a component of additional paid-in capital, was $16 million, net of issue costs, which represented the initial estimated fair value on the date of issuance.

- Definition

The entire disclosure for equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-8A

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-13

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-13

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-14

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 235
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477968/946-235-50-2

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 235
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477968/946-235-50-2

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 505
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478448/946-505-50-6

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480237/815-40-50-6

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480008/505-10-S99-1

Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 505
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/505/tableOfContent

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-13

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (g)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-13

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-13

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-14

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-14

Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 16
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-16

Reference 17: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-18

Reference 18: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-18

Reference 19: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-18

+ Details

Long-Lived Assets (Impairments) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Long-Lived Assets.
Aggregate loss on impairment of assets held for sale	$ 3,049	$ 772	$ 57
Aggregate loss on impairment of assets held for sale, net of tax	$ 3,040	$ 755
Loss associated with impairment, net of tax (per share)	$ 3.16	$ 0.82	$ 0.07
Aggregate loss on impairment of assets held for sale, tax effect		$ 0	$ 0

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2025

Income Taxes

Components of the provision (benefit) for income taxes

The components of our income tax provision (benefit) were as follows (in millions):


		Years ended December 31,
		2025			2024			2023
Current tax expense (benefit)		$	78		$	31		$	(5)
Deferred tax expense (benefit)			(111)			(42)			18
Income tax expense (benefit)		$	(33)		$	(11)		$	13

Reconciliation of the differences between income tax expense computed at the Swiss holding company statutory rate and the reported provision for income taxes


	Year ended
	December 31, 2025
Switzerland, federal statutory tax rate	$	(220)	7.48%
Switzerland, cantonal taxes		(13)	0.44%
Switzerland, changes in valuation allowance		131	(4.46)%

Non-Switzerland tax effects
Bermuda, changes in valuation allowance		212	(7.21)%
Bermuda, tax rate differential		(107)	3.64%
Bermuda, other, net		13	(0.42)%
United States, tax rate differential		65	(2.21)%
United States, changes in valuation allowance		20	(0.68)%
United States, other, net		(15)	0.51%
Luxembourg, changes due to operational restructuring		43	(1.46)%
Luxembourg, changes in valuation allowance		(20)	0.68%
Luxembourg, other, net		8	(0.27)%
Norway, changes in currency exchange		(17)	0.56%
Norway, other, net		24	(0.82)%
Hungary, changes in valuation allowance		26	(0.88)%
Hungary, changes in currency exchange		(25)	0.85%
Hungary, other, net		1	(0.02)%
Brazil, tax rate differential		16	(0.54)%
Brazil, other, net		(19)	0.65%
United Kingdom, changes in valuation allowance		(36)	1.22%
United Kingdom, other, net		(5)	0.15%
Other, net		9	(0.30)%

Changes in unrecognized tax benefits		(123)	4.18%

Other adjustments
Switzerland, changes due to operational restructuring		(13)	0.44%
Switzerland, other, net		12	(0.40)%
Effective tax rate	$	(33)	1.13%


			Years ended December 31,
			2024			2023
Income tax benefit at Swiss federal statutory rate			$	(40)		$	(74)
Earnings subject to rates different than the Swiss federal statutory rate				74			129
Changes in valuation allowance				208			(23)
Tax attribute expirations				185			—
Deemed profits taxes				12			11
Withholding taxes				4			5
Changes in unrecognized tax benefits, net				(4)			(37)
Changes due to organizational restructuring				(452)			—
Other, net				2			2
Income tax expense (benefit)			$	(11)		$	13

Schedule of reconciliation of unrecognized tax benefits, excluding interest and penalties

The changes to unrecognized tax benefits, excluding interest and penalties that we recognize as a component of income tax expense, were as follows (in millions):


		Years ended December 31,
			2025			2024			2023
Balance, beginning of period		$	407		$	449		$	444
Additions for current year tax positions			49			13			45
Additions for prior year tax positions			39			11			5
Reductions due to settlements			(203)			(30)			(5)
Reductions related to statute of limitation expirations and changes in law			(8)			(19)			(14)
Reductions for prior year tax positions			—			(17)			(26)
Balance, end of period		$	284		$	407		$	449

Schedule of unrecognized tax benefits, including related interest and penalties

Our unrecognized tax benefits were as follows (in millions):


	December 31,
		2025			2024
Unrecognized tax benefits, excluding interest and penalties	$	284		$	407
Interest and penalties		18			7
Unrecognized tax benefits, including interest and penalties	$	302		$	414

Schedule of components of income taxes paid, net of refunds received, disaggregated by country

The components of our income taxes paid, net of refunds received, disaggregated by country, were as follows (in millions):


		Year ended
		December 31,
		2025
Switzerland, federal		$	2
Switzerland, cantonal			2
Total Switzerland			4

Brazil			17
United States			14
Angola			9
Australia			5
India			5
Hungary			4
Other countries (a)			3
Total tax payments, net of refunds received		$	61

(a)

The aggregate income taxes paid, net of refunds received, in other countries that individually represented less than 5 percent of total income taxes paid, net.

Significant components of deferred tax assets and liabilities

The significant components of our deferred tax assets and liabilities were as follows (in millions):


		December 31,
		2025			2024
Deferred tax assets
Net operating loss carryforwards		$	1,985		$	1,541
Swiss historic depreciation and financing asset costs			1,034			1,053
Interest expense limitation			54			87
United Kingdom charter limitation			53			53
Accrued costs and expenses			33			20
Contract liabilities			6			22
Accrued payroll costs not currently deductible			11			12
Other			69			69
Valuation allowance			(2,479)			(2,089)
Total deferred tax assets, net of allowance			766			768

Deferred tax liabilities
Depreciation			(1,068)			(1,214)
Other			(41)			(8)
Total deferred tax liabilities			(1,109)			(1,222)

Deferred tax liabilities, net		$	(343)		$	(454)

Leases (Lease Costs) (Details) - USD ($) $ in Millions	12 Months Ended
Leases (Lease Costs) (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Leases
Short-term lease costs	$ 15	$ 10	$ 4
Operating lease costs	10	16	14
Finance lease costs, amortization of right-of-use asset	20	20	20
Finance lease costs, interest on lease liability	20	24	27
Total lease costs	$ 65	$ 70	$ 65

Debt (Credit Agreements) (Details) $ in Millions	12 Months Ended
Debt (Credit Agreements) (Details) $ in Millions	Dec. 31, 2025 USD ($)	Dec. 31, 2024 USD ($)
Debt
Aggregate principal amount outstanding	$ 5,686	$ 6,944
Restricted cash and cash equivalents	377	381
Five-Year Revolving Credit Facility
Debt
Borrowing capacity, maximum	$ 510
Commitment fee (as a percent)	0.625%
Credit facility amount outstanding	$ 0
Letters of credit issued and outstanding	48
Credit facility available borrowing capacity	$ 462
Variable rate spread adjustment (as a percent)	0.10%
Spread on variable rate basis (as a percent)	2.875%
Debt Instrument, Variable Interest Rate, Type [Extensible Enumeration]	us-gaap:SecuredOvernightFinancingRateSofrMember
Early maturity trigger, principal due within 91 days	$ 325
Early maturity trigger available cash	250
Permitted commitment increase	$ 250
Minimum guarantee coverage ratio	3
Minimum collateral coverage ratio.	2.1
Debt to capitalization ratio	0.6
Minimum liquidity	$ 200
Aggregate carrying amount assets pledged	4,180
Cross default trigger under credit facility	$ 125
Five-Year Revolving Credit Facility \| Minimum
Debt
Commitment fee (as a percent)	0.375%
Five-Year Revolving Credit Facility \| Maximum
Debt
Commitment fee (as a percent)	1.00%
Senior Secured Notes
Debt
Aggregate carrying amount assets pledged	$ 5,190
Restricted cash and cash equivalents	358
4.50% Shipyard Loans due September 2027
Debt
Aggregate principal amount outstanding	209	329
4.50% Shipyard Loans due September 2027 \| Deepwater Atlas
Debt
Aggregate principal amount outstanding	159
4.50% Shipyard Loans due September 2027 \| Deepwater Titan
Debt
Aggregate principal amount outstanding	50
7.35% Senior Notes due December 2041
Debt
Aggregate principal amount outstanding	$ 88	$ 177
Interest rate, as adjusted (as a percent)	9.35%

Debt (Tables)

12 Months Ended

Dec. 31, 2025

Debt

Schedule of debt

The aggregate principal amounts and aggregate carrying amounts, including a bifurcated compound exchange feature and unamortized debt-related balances, such as discounts, premiums and issue costs, were as follows (in millions):


		Principal amount					Carrying amount
		December 31,			December 31,		December 31,			December 31,
		2025			2024		2025			2024
4.00% Senior Guaranteed Exchangeable Bonds due December 2025	(a)	$	—		$	234	$	—		$	227
6.875% Senior Secured Notes due February 2027	(b)		—			330		—			328
8.00% Senior Notes due February 2027	(c)		—			655		—			653
7.45% Notes due April 2027	(d)		52			52		52			52
8.00% Debentures due April 2027	(d)		22			22		22			22
4.50% Shipyard Loans due September 2027	(e)		209			329		202			310
8.375% Senior Secured Notes due February 2028	(b)		425			525		421			518
7.00% Notes due June 2028	(e)		209			261		210			263
8.00% Senior Secured Notes due September 2028	(b)		235			295		233			292
8.25% Senior Notes due May 2029	(c)		900			900		889			887
4.625% Senior Guaranteed Exchangeable Bonds due September 2029	(c)		259			259		292			286
8.75% Senior Secured Notes due February 2030	(f)		881			999		868			981
7.50% Notes due April 2031	(d)		396			396		395			395
8.50% Senior Notes due May 2031	(c)		900			900		888			886
7.875% Senior Guaranteed Notes due October 2032	(a)		500			—		493			—
6.80% Senior Notes due March 2038	(d)		610			610		605			605
7.35% Senior Notes due December 2041	(d)		88			177		87			176
Total debt			5,686			6,944		5,657			6,881

Less debt due within one year
4.00% Senior Guaranteed Exchangeable Bonds due December 2025	(a)		—			234		—			227
6.875% Senior Secured Notes due February 2027	(b)		—			83		—			82
4.50% Shipyard Loans due September 2027	(e)		136			120		129			108
8.375% Senior Secured Notes due February 2028	(b)		135			100		133			97
8.00% Senior Secured Notes due September 2028	(b)		70			60		69			59
8.75% Senior Secured Notes due February 2030	(f)		117			117		114			113
Total debt due within one year			458			714		445			686
Total long-term debt		$	5,228		$	6,230	$	5,212		$	6,195

(a)

(b)

(c)

(d)	Transocean International Limited is the issuer of the notes and debentures (the “Legacy Guaranteed Notes”). The Legacy Guaranteed Notes are fully and unconditionally, jointly and severally, guaranteed by Transocean Ltd.

(e)	The subsidiary borrowers under the Shipyard Loans and the subsidiary issuer of the registered notes are wholly owned indirect subsidiaries of Transocean International Limited. The loans and notes are fully and unconditionally guaranteed by Transocean International Limited.

(f)	Transocean International Limited is the issuer of the unregistered notes. The senior secured notes are fully and unconditionally guaranteed on an unsecured basis by Transocean Ltd. and on a limited senior secured basis by each of the wholly owned subsidiary owners of the collateral rigs.

Scheduled maturities and installments of debt

At December 31, 2025, the scheduled repayments were as follows (in millions):


		Total
Years ending December 31,
2026		$	458
2027			435
2028			612
2029			1,277
2030			411
Thereafter			2,493
Total principal amount of debt			5,686
Total unamortized debt-related balances, net			(155)
Bifurcated compound exchange feature, at estimated fair value			126
Total carrying amount of debt		$	5,657

Schedule of convertible debt

We recognized interest expense for our exchangeable bonds as follows (in millions):


		Years ended December 31,
	2025		2024		2023
Contractual interest	$	18	$	21	$	24
Amortization		20		20		19
(Gain) loss on adjustment to bifurcated compound exchange feature		(10)		(214)		127
Total	$	28	$	(173)	$	170

Schedule of debt retirements

During the three years ended December 31, 2025, we retired certain notes for which the aggregate principal amounts, cash payments and recognized gain or loss were as follows (in millions):


	2025						2024						2023
	Redeem or repurchase		Tender		Total		Redeem		Tender		Total		Redeem
5.375% Senior Secured Notes due May 2023	$	—	$	—	$	—	$	—	$	—	$	—	$	243
5.875% Senior Secured Notes due January 2024		—		—		—		—		—		—		311
7.75% Senior Secured Notes due October 2024		—		—		—		—		—		—		240
6.25% Senior Secured Notes due December 2024		—		—		—		—		—		—		250
6.125% Senior Secured Notes due August 2025		—		—		—		—		—		—		336
7.25% Senior Notes due November 2025		—		—		—		105		249		354		—
7.50% Senior Notes due January 2026		—		—		—		569		—		569		—
11.50% Senior Guaranteed Notes due January 2027		—		—		—		91		596		687		—
8.00% Senior Notes due February 2027		655		—		655		87		—		87		—
6.875% Senior Secured Notes due February 2027		248		—		248		—		—		—		—
7.00% Notes due June 2028		36		16		52		—		—		—		—
7.35% Senior Notes due December 2041		1		89		90		—		—		—		—
Aggregate principal amount of debt retired	$	940	$	105	$	1,045	$	852	$	845	$	1,697	$	1,380

Aggregate cash payment	$	939	$	100	$	1,039	$	862	$	886	$	1,748	$	1,402
Aggregate net gain (loss)	$	(1)	$	4	$	3	$	17	$	144	$	161	$	(32)

Schedule II - Valuation and Qualifying Accounts (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Allowance for credit losses
Reserves and allowances deducted from asset accounts
Balance, beginning of period	$ 2	$ 2	$ 2
Balance, end of period	2	2	2
Allowance for excess materials and supplies
Reserves and allowances deducted from asset accounts
Balance, beginning of period	178	198	199
Additions: charged to cost and expenses	17	7	6
Deductions	(55)	(27)	(7)
Balance, end of period	140	178	198
Valuation allowance on deferred tax assets
Reserves and allowances deducted from asset accounts
Balance, beginning of period	2,089	1,884	1,910
Additions: charged to cost and expenses	390	208
Deductions		(3)	(26)
Balance, end of period	$ 2,479	$ 2,089	$ 1,884

Debt (Debt Issuances) (Details) - USD ($) $ in Millions	1 Months Ended				12 Months Ended
Debt (Debt Issuances) (Details) - USD ($) $ in Millions	Oct. 31, 2025	Apr. 30, 2024	Oct. 31, 2023	Jan. 31, 2023	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	Jun. 30, 2024
Debt
Proceeds from issuance of debt		$ 1,770			$ 492	$ 1,770	$ 1,983
Orion/Transocean Norge
Debt
Equity ownership (as a percent)							33.00%
Orion/Transocean Norge \| Orion/Transocean Norge
Debt
Equity ownership (as a percent)								67.00%
8.00% Senior Secured Notes due September 2028
Debt
Debt instrument face value			$ 325
Debt instrument interest rate stated percentage			8.00%
Proceeds from issuance of debt			$ 319
8.00% Senior Notes due February 2027
Debt
Debt instrument interest rate stated percentage					8.00%	8.00%		8.00%
8.00% Senior Notes due February 2027 \| Orion/Transocean Norge
Debt
Debt instrument face value								$ 130
Debt instrument interest rate stated percentage								8.00%
8.25% Senior Notes due May 2029
Debt
Debt instrument face value		$ 900
Debt instrument interest rate stated percentage		8.25%			8.25%
8.25% Senior Notes due May 2029 \| Redemption of all or a portion of principal amount of debt
Debt
Redemption price of debt instrument (as a percent)		100.00%
8.50% Senior Notes due May 2031
Debt
Debt instrument face value		$ 900
Debt instrument interest rate stated percentage		8.50%			8.50%
8.50% Senior Notes due May 2031 \| Redemption of all or a portion of principal amount of debt
Debt
Redemption price of debt instrument (as a percent)		100.00%
7.875% Senior Guaranteed Notes due October 2032
Debt
Debt instrument face value	$ 500
Debt instrument interest rate stated percentage	7.875%				7.875%
Proceeds from issuance of debt	$ 492
7.875% Senior Guaranteed Notes due October 2032 \| Redemption of up to 40% of principal amount of debt
Debt
Redemption price of debt instrument (as a percent)	107.875%
7.875% Senior Guaranteed Notes due October 2032 \| Redemption of all or a portion of principal amount of debt
Debt
Redemption price of debt instrument (as a percent)	100.00%
7.875% Senior Guaranteed Notes due October 2032 \| Maximum \| Redemption of up to 40% of principal amount of debt
Debt
Principal amount of debt redeemed (as a percent)	40.00%
Senior Secured Notes
Debt
Redemption price of debt instrument (as a percent)					100.00%
8.75% Senior Secured Notes due February 2030
Debt
Debt instrument face value				$ 1,175
Debt instrument interest rate stated percentage				8.75%	8.75%
Proceeds from issuance of debt				$ 1,148
8.375% Senior Secured Notes due February 2028
Debt
Debt instrument face value				$ 525
Debt instrument interest rate stated percentage				8.375%	8.375%
Proceeds from issuance of debt				$ 516

Benefit Plans (Defined Benefit Pension and Other Postemployment Plan Assets) (Details) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
	Aug. 31, 2025	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Fair value of plan assets
Total investments		$ 1,381	$ 1,374	$ 1,450
Funding contributions
Employer contributions		8	$ 2	8
Expected defined plan contributions next year		5
Projected pension benefits payments
2026		95
2027		95
2028		95
2029		97
2030		98
2031-2035		$ 499
UNITED STATES
Weighted-average target allocations of the investments
Total target allocation percentage		100.00%	100.00%
Total actual allocation percentage		100.00%	100.00%
UNITED STATES \| Fixed income securities
Weighted-average target allocations of the investments
Total target allocation percentage			99.00%
Total actual allocation percentage			99.00%
UNITED STATES \| Other investments
Weighted-average target allocations of the investments
Total target allocation percentage		100.00%	1.00%
Total actual allocation percentage		100.00%	1.00%
UNITED KINGDOM
Weighted-average target allocations of the investments
Total target allocation percentage		100.00%	100.00%
Total actual allocation percentage		100.00%	100.00%
UNITED KINGDOM \| Equity securities
Weighted-average target allocations of the investments
Total target allocation percentage			20.00%
Total actual allocation percentage			26.00%
UNITED KINGDOM \| Fixed income securities
Weighted-average target allocations of the investments
Total target allocation percentage		95.00%	73.00%
Total actual allocation percentage		90.00%	65.00%
UNITED KINGDOM \| Other investments
Weighted-average target allocations of the investments
Total target allocation percentage		5.00%	7.00%
Total actual allocation percentage		10.00%	9.00%
Transocean Plans
Funding contributions
Expected defined plan contributions next year		$ 3
Transocean Plans \| Level 1
Fair value of plan assets
Total investments		61	$ 1,164
Transocean Plans \| Level 2
Fair value of plan assets
Total investments		217	210
Transocean Plans \| Level 3
Fair value of plan assets
Total investments		1,103
Transocean Plans \| Mutual funds \| Level 1
Fair value of plan assets
Total investments			1,155
Transocean Plans \| Mutual funds \| Level 2
Fair value of plan assets
Total investments		206	191
Transocean Plans \| Non-U.S. equity funds \| Level 1
Fair value of plan assets
Total investments			4
Transocean Plans \| Non-U.S. equity funds \| Level 2
Fair value of plan assets
Total investments		5	55
Transocean Plans \| Bond funds \| Level 1
Fair value of plan assets
Total investments			1,151
Transocean Plans \| Bond funds \| Level 2
Fair value of plan assets
Total investments		201	136
Transocean Plans \| Other investments \| Level 1
Fair value of plan assets
Total investments		61	9
Transocean Plans \| Other investments \| Level 2
Fair value of plan assets
Total investments		11	19
Transocean Plans \| Other investments \| Level 3
Fair value of plan assets
Total investments		1,103
Transocean Plans \| Cash and money market funds \| Level 1
Fair value of plan assets
Total investments		61	9
Transocean Plans \| Cash and money market funds \| Level 2
Fair value of plan assets
Total investments			2
Transocean Plans \| Buy-in contract \| Level 3
Fair value of plan assets
Total investments		1,103
Transocean Plans \| Synthetic leveraged credit fund \| Level 2
Fair value of plan assets
Total investments		11	17
Transocean Plans \| UNITED STATES
Fair value of plan assets
Total investments		1,158	1,164	1,211
Funding contributions
Employer contributions		7
Projected pension benefits payments
2026		85
2027		85
2028		85
2029		86
2030		86
2031-2035		431
Transocean Plans \| UNITED STATES \| Level 1
Fair value of plan assets
Total investments		55	1,162
Transocean Plans \| UNITED STATES \| Level 2
Fair value of plan assets
Total investments			2
Transocean Plans \| UNITED STATES \| Level 3
Fair value of plan assets
Total investments		1,103
Transocean Plans \| UNITED STATES \| Mutual funds \| Level 1
Fair value of plan assets
Total investments			1,153
Transocean Plans \| UNITED STATES \| Mutual funds \| Level 2
Fair value of plan assets
Total investments			2
Transocean Plans \| UNITED STATES \| Non-U.S. equity funds \| Level 1
Fair value of plan assets
Total investments			4
Transocean Plans \| UNITED STATES \| Bond funds \| Level 1
Fair value of plan assets
Total investments			1,149
Transocean Plans \| UNITED STATES \| Bond funds \| Level 2
Fair value of plan assets
Total investments			2
Transocean Plans \| UNITED STATES \| Other investments \| Level 1
Fair value of plan assets
Total investments		55	9
Transocean Plans \| UNITED STATES \| Other investments \| Level 3
Fair value of plan assets
Total investments		1,103
Transocean Plans \| UNITED STATES \| Cash and money market funds \| Level 1
Fair value of plan assets
Total investments		55	9
Transocean Plans \| UNITED STATES \| Buy-in contract \| Level 3
Postemployment Benefit Plans
Defined Benefit Plan, Plan Assets Level 3 Reconciliation, Increase for Purchase	$ 1,107
Fair value of plan assets
Total investments		1,103
Transocean Plans \| UNITED KINGDOM
Fair value of plan assets
Total investments		223	210	$ 239
Projected pension benefits payments
2026		8
2027		8
2028		9
2029		10
2030		11
2031-2035		67
Transocean Plans \| UNITED KINGDOM \| Level 1
Fair value of plan assets
Total investments		6	2
Transocean Plans \| UNITED KINGDOM \| Level 2
Fair value of plan assets
Total investments		217	208
Transocean Plans \| UNITED KINGDOM \| Mutual funds \| Level 2
Fair value of plan assets
Total investments		206	191
Transocean Plans \| UNITED KINGDOM \| Non-U.S. equity funds \| Level 2
Fair value of plan assets
Total investments		5	55
Transocean Plans \| UNITED KINGDOM \| Bond funds \| Level 2
Fair value of plan assets
Total investments		201	136
Transocean Plans \| UNITED KINGDOM \| Other investments \| Level 1
Fair value of plan assets
Total investments		6	2
Transocean Plans \| UNITED KINGDOM \| Other investments \| Level 2
Fair value of plan assets
Total investments		11	17
Transocean Plans \| UNITED KINGDOM \| Cash and money market funds \| Level 1
Fair value of plan assets
Total investments		6	2
Transocean Plans \| UNITED KINGDOM \| Synthetic leveraged credit fund \| Level 2
Fair value of plan assets
Total investments		11	17
OPEB Plans
Funding contributions
Employer contributions		1	$ 2
Expected defined plan contributions next year		2
Projected pension benefits payments
2026		2
2027		2
2028		1
2029		1
2030		1
2031-2035		$ 1

Revenues (Changes in Contract Liabilities) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024
Changes to contract liabilities
Total contract liabilities, beginning of period	$ 443	$ 398
Decrease due to recognition of revenues for goods and services	(260)	(243)
Increase due to goods and services transferred over time	90	288
Total contract liabilities, end of period	$ 273	$ 443

Long-Lived Assets (Tables)

12 Months Ended

Dec. 31, 2025

Long-Lived Assets.

Schedule of long-lived assets of the entity's continuing operations by country

The aggregate carrying amount of our long-lived assets, including our property and equipment and our right-of-use assets, measured net of accumulated depreciation or amortization, disaggregated by country in which they were located, was as follows (in millions):


	December 31,
	2025		2024
Long-lived assets
U.S.	$	6,487	$	6,727
Norway		1,941		2,017
Brazil		1,914		1,993
Greece		611		2,531
Other countries (a)		2,050		3,008
Total long-lived assets	$	13,003	$	16,276

(a)

The aggregate net carrying amount of long-lived assets located in other countries that individually represented less than 10 percent of total long-lived assets on both dates.

Business (Details)		12 Months Ended
Business (Details)	Feb. 09, 2026 $ / shares	Dec. 31, 2025 segment item $ / shares	Dec. 31, 2024 $ / shares	Jan. 01, 2024 $ / shares	Dec. 31, 2023 SFr / shares
Business
Number of mobile offshore drilling units		27
Number of operating segments \| segment		1
Shares, Par value \| (per share)		$ 0.1	$ 0.1	$ 0.1	SFr 0.1
Valaris Limited \| Subsequent Event
Business
Shares, Par value \| $ / shares	$ 0.1
Share exchange ratio	15.235
Valaris Limited \| Valaris Limited \| Subsequent Event
Business
Shares, Par value \| $ / shares	$ 0.01
Ultra-deepwater drillships
Business
Number of mobile offshore drilling units		20
Harsh environment semisubmersibles
Business
Number of mobile offshore drilling units		7