UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

PURSUANT TO SECTION 13 OR 15(d) OF THE

SECURITIES EXCHANGE ACT OF 1934

Date of Report (Date of earliest event reported): May 2, 2012

TRANSOCEAN LTD.

(Exact name of registrant as specified in its charter)

Registrant’s telephone number, including area code: +41 (22) 930-9000

(Former name or former address, if changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

o    Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o    Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o    Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o    Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Item 2.02.  Results of Operations and Financial Condition.

Our press release dated May 2, 2012, concerning financial results for the first quarter ended March 31, 2012, furnished as Exhibit 99.1 to this report, is incorporated by reference herein.

Item 9.01.  Financial Statements and Exhibits.

(d)  Exhibits.

2

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

3

Index to Exhibits

4

Exhibit 99.1

TRANSOCEAN LTD. REPORTS FIRST QUARTER 2012 RESULTS

·                  First quarter 2012 revenues were $2.331 billion compared with $2.422 billion in the fourth quarter 2011,

·                  First quarter 2012 net income attributable to controlling interest was $42 million, which included $184 million of net unfavorable items.   This compares with the fourth quarter 2011 net loss attributable to controlling interest of $6.119 billion, which included $6.176 billion of net unfavorable items,

·                  Revenue efficiency(1) was 90.4 percent in the first quarter, compared with 91.9 percent in the fourth quarter 2011,

·                  Fleet utilization(2) was 61 percent in the first quarter, unchanged from the fourth quarter 2011,

·                  First quarter 2012 operating and maintenance expenses were $1.410 billion.  Excluding $1.0 billion for estimated loss contingencies associated with the Macondo Well incident, fourth quarter 2011 operating and maintenance expenses were $1.565 billion,

·                  Cash flows from operating activities were $540 million in the first quarter, which compares with $563 million in the fourth quarter 2011,

·                  First quarter 2012 Annual Effective Tax Rate(3) was 25.5 percent compared with 59.6 percent in the fourth quarter 2011, and

·                  New contracts totaling $834 million were secured in the Fleet Status Report periods February 14, 2012 through April 18, 2012.  Since April 18, 2012, additional contracts totaling $430 million were secured.

ZUG, SWITZERLAND — Transocean Ltd. (NYSE: RIG) (SIX: RIGN) today reported net income attributable to controlling interest of $42 million, or $0.12 per diluted share, for the three months ended March 31, 2012. First quarter 2012 results include net unfavorable items of $184 million, or $0.52 per diluted share.  The results compare with net income attributable to controlling interest of $310 million, or $0.96 per diluted share, for the three months ended March 31, 2011.  First quarter 2011 results included net favorable items of $139 million, or $0.43 per diluted share, primarily associated with the gain on sale of the Trident 20, partially offset by charges mainly related to unfavorable discrete tax items.

Net unfavorable items, after tax, impacting the first quarter of 2012 include the following:

·                  $118 million, or $0.34 per diluted share, increase in the charge associated with the completion of the measurement of the estimated goodwill impairment recorded in the fourth quarter 2011 for the contract drilling services reporting unit,

·                  $62 million, or $0.17 per diluted share, impairment of the intangible assets of ADTI, the drilling management services reporting unit,

·                  $29 million, or $0.08 per diluted share, of favorable discrete tax items,

·                  $17 million, or $0.05 per diluted share, impairment charge associated with the sale of GSF Rig 136,

·                  $15 million, or $0.04 per diluted share, loss associated with the sale of Challenger Minerals (North Sea) Limited and the impairment of the properties of Challenger Minerals Inc., and

·                  $1 million associated with the company’s acquisition of Aker Drilling.

Operations Quarterly Review

Revenues for the three months ended March 31, 2012 were $2.331 billion, compared with revenues of $2.422 billion during the three months ended December 31, 2011.  Contract drilling revenues decreased $35 million due mainly to lower revenue efficiency primarily on Deepwater and Midwater Floaters.  Total fleet revenue efficiency was 90.4 percent for the first quarter, compared with 91.9 percent in the fourth quarter 2011.  Other revenues decreased $54 million to $117 million for the first quarter 2012, compared with $171 million in the prior quarter, primarily due to decreased levels of low-margin drilling management services activity.

Operating and maintenance expenses totaled $1.410 billion for the first quarter 2012.  This compares with $1.565 billion in the fourth quarter 2011, which excludes $1.0 billion for estimated loss contingencies associated with the Macondo Well incident.  The sequential decline in operating and maintenance expenses relates to the timing of certain projects and various other items.  These include approximately $70 million in net lower costs incurred on rigs undergoing shipyard, maintenance, repair and equipment certification projects during the period; approximately $40 million associated with reduced activity in the company’s low-margin drilling management services reporting unit; and approximately $35 million related to the fourth quarter 2011 termination of the Deepwater Expedition contract.

Depreciation and amortization expense was $351 million in the first quarter 2012 compared with $374 million in the prior quarter.  The $23 million decrease was due mainly to assets that are now fully depreciated and the impact of Standard Jackups classified as held for sale or sold.

General and administrative expenses were $69 million for the first quarter 2012 compared with $88 million in the previous quarter, including $1 million and $17 million, respectively, associated with the Aker Drilling acquisition.

Annual Effective Tax Rate

Transocean’s Annual Effective Tax Rate (3) for the first quarter 2012, which excludes various discrete items, was 25.5 percent.  This compares with 59.6 percent for the prior quarter.

Other Items

For the first quarter, interest expense, net of amounts capitalized, was $180 million, compared with $178 million in the fourth quarter 2011.  Capitalized interest for the first quarter 2012 was $13 million compared with $10 million in the prior quarter.   Interest income decreased to $15 million in the first quarter, compared with $17 million in the fourth quarter 2011.

Cash flows from operating activities decreased $23 million to $540 million for the first quarter 2012 compared with $563 million for the fourth quarter 2011.  Capital expenditures decreased to $260 million for the first quarter compared with $350 million in the fourth quarter of 2011. The lower capital expenditures were primarily due to the timing of shipyard milestone payments associated with the company’s newbuild program.

Forward-Looking Statements

Statements included in this news release, including those regarding estimates of Transocean’s goodwill or long-lived asset impairments and the estimated loss contingencies associated with the Macondo Well incident, are forward-looking statements that involve certain assumptions. These statements are based on currently available competitive, financial, and economic data along with our current operating plans and involve risks and uncertainties including, but not limited to, market conditions, Transocean’s results of operations and other factors detailed in “Risk Factors” and elsewhere in Transocean’s filings with the Securities and Exchange Commission. Should one or more of these risks or uncertainties materialize (or the other consequences of such a development worsen), or should underlying assumptions prove incorrect, actual outcomes may vary materially from those forecasted or expected. Transocean disclaims any intention or obligation to update publicly or revise such statements, whether as a result of new information, future events or otherwise.

Conference Call Information

Transocean will conduct a teleconference call at 10:00 a.m. EDT, 4:00 p.m. CEST, on Thursday, May 3, 2012. To participate, dial +1 800-768-6563 or +1 785-830-7991 and refer to confirmation code 9219164 approximately 10 minutes prior to the scheduled start time of the call.

In addition, the conference call will be simultaneously broadcast over the Internet in a listen-only mode and can be accessed by logging onto Transocean’s website at www.deepwater.com and selecting “Investor Relations.” A file containing three charts that may be discussed during the conference call, titled “1Q12 Charts,” has been posted to Transocean’s website and can also be found by selecting “Investor Relations/Quarterly Toolkit.” The conference call may also be accessed via the Internet at www.CompanyBoardroom.com by typing in Transocean’s New York Stock Exchange trading symbol, “RIG.”

A telephonic replay of the conference call should be available after 1:00 p.m. EDT, 7:00 p.m. CEST, on May 3, 2012, and can be accessed by dialing +1 719-457-0820 or +1 888-203-1112 and referring to the confirmation code 9219164. Also, a replay will be available through the Internet and can be accessed by visiting either of the above-referenced internet addresses. Both replay options will be available for approximately 30 days.

About Transocean

Transocean is a leading international provider of offshore contract drilling services for oil and gas wells.  We own or have partial ownership interests in and operate a fleet of 129 mobile offshore drilling units consisting of 50 High-Specification Floaters (Ultra-Deepwater, Deepwater and Harsh-Environment semisubmersibles and drillships), 25 Midwater Floaters, nine High-Specification Jackups, 44 Standard Jackups and one swamp barge.  In addition, we have two Ultra-Deepwater drillships and four High-Specification Jackups under construction.  The company specializes in technically demanding sectors of the global offshore drilling business with a particular focus on deepwater and harsh environment drilling services.  We believe we operate one of the most versatile offshore drilling fleets in the world.

(1) Revenue efficiency is defined as actual revenue divided by the highest amount of total revenue which could have been earned during the relevant period(s). See the accompanying schedule entitled “Revenue Efficiency.”

(2) Utilization is defined as the total actual number of revenue earning days in the period as a percentage of the total number of calendar days in the period for all drilling rigs in the company’s fleet. See the accompanying schedule entitled “Utilization.”

(3) Annual Effective Tax Rate is defined as income tax expense from continuing operations excluding various discrete items (such as changes in estimates and tax on items excluded from income before income tax expense) divided by income from continuing operations before income tax expense excluding gains on sales and similar items pursuant to the accounting standards for income taxes. See the accompanying schedule entitled “Supplemental Effective Tax Rate Analysis.”

(4) Effective Tax Rate is defined as income tax expense from continuing operations divided by income from continuing operations before income taxes. See the accompanying schedule entitled “Supplemental Effective Tax Rate Analysis.”

For more information about Transocean, please visit the website at www.deepwater.com.

TRANSOCEAN LTD. AND SUBSIDIARIES

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS

(In millions, except per share data)

(Unaudited)

TRANSOCEAN LTD. AND SUBSIDIARIES

CONDENSED CONSOLIDATED BALANCE SHEETS

(In millions, except share data)

(Unaudited)

TRANSOCEAN LTD. AND SUBSIDIARIES

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS

(In millions)

(Unaudited)

TRANSOCEAN LTD. AND SUBSIDIARIES

FLEET OPERATING STATISTICS

(1)          Average daily revenue is defined as contract drilling revenue earned per revenue earning day in the period.  A revenue earning day is defined as a day for which a rig earns dayrate after commencement of operations.

TRANSOCEAN LTD. AND SUBSIDIARIES

FLEET OPERATING STATISTICS (continued)

(2)          Utilization is defined as the total actual number of revenue earning days in the period as a percentage of the total number of calendar days in the period for all drilling rigs in our fleet.

(3)          Revenue efficiency is defined as actual revenue divided by the highest amount of total revenue which could have been earned during the relevant period(s).

TRANSOCEAN LTD. AND SUBSIDIARIES

SUPPLEMENTAL EFFECTIVE TAX RATE ANALYSIS

(In US$ millions, except percentages)