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 even reported): March 1, 2013

TRANSOCEAN LTD.

(Exact name of registrant as specified in its charter)

+41 (22) 930-9000

(Registrant’s telephone number, including area code)

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)

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

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

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

Item 7.01.  Regulation FD Disclosure

Furnished as Exhibit 99.1 to this Current Report on Form 8-K is the Company’s standalone Swiss statutory financial statements which comprise the statement of operations, balance sheet and notes pages for the year ended December 31, 2012, which financial statements and reports thereon are incorporated herein by reference.

Item 9.01. Financial Statements and Exhibits

(d) Exhibits

The exhibit to this report furnished pursuant to Item 7.01 is as follows:

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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, on March 1, 2013.

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Index to Exhibit

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Exhibit 99.1

To the Annual General Meeting of

Transocean Ltd., Steinhausen

Zurich, March 1, 2013

Report of the statutory auditor on the financial statements

As statutory auditor, we have audited the financial statements of Transocean Ltd., which comprise the statement of operations, balance sheet and notes pages (SR-2 to SR-20), for the year ended December 31, 2012.

Board of Directors’ responsibility

The Board of Directors is responsible for the preparation of the financial statements in accordance with the requirements of Swiss law and the company’s articles of incorporation. This responsibility includes designing, implementing and maintaining an internal control system relevant to the preparation of financial statements that are free from material misstatement, whether due to fraud or error. The Board of Directors is further responsible for selecting and applying appropriate accounting policies and making accounting estimates that are reasonable in the circumstances.

Auditor’s responsibility

Our responsibility is to express an opinion on these financial statements based on our audit. We conducted our audit in accordance with Swiss law and Swiss Auditing Standards. Those standards require that we plan and perform the audit to obtain reasonable assurance whether the financial statements are free from material misstatement.

An audit involves performing procedures to obtain audit evidence about the amounts and disclosures in the financial statements. The procedures selected depend on the auditor’s judgment, including the assessment of the risks of material misstatement of the financial statements, whether due to fraud or error. In making those risk assessments, the auditor considers the internal control system relevant to the entity’s preparation of the financial statements in order to design audit procedures that are appropriate in the circumstances, but not for the purpose of expressing an opinion on the effectiveness of the entity’s internal control system. An audit also includes evaluating the appropriateness of the accounting policies used and the reasonableness of accounting estimates made, as well as evaluating the overall presentation of the financial statements. We believe that the audit evidence we have obtained is sufficient and appropriate to provide a basis for our audit opinion.

Opinion

In our opinion, the financial statements for the year ended December 31, 2012 comply with Swiss law and the company’s articles of incorporation.

Report on other legal requirements

We confirm that we meet the legal requirements on licensing according to the Auditor Oversight Act (AOA) and independence (article 728 CO and article 11 AOA) and that there are no circumstances incompatible with our independence.

In accordance with article 728a paragraph 1 item 3 CO and Swiss Auditing Standard 890, we confirm that an internal control system exists, which has been designed for the preparation of financial statements according to the instructions of the Board of Directors.

We further confirm that the proposed appropriation of available earnings complies with Swiss law and the company’s articles of incorporation. We recommend that the financial statements submitted to you be approved.

TRANSOCEAN LTD.

STATEMENT OF OPERATIONS

(in CHF thousands)

See accompanying notes.

SR-2

TRANSOCEAN LTD.
BALANCE SHEET

(in CHF thousands)

See accompanying notes.

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TRANSOCEAN LTD.

NOTES TO STATUTORY FINANCIAL STATEMENTS

Note 1 — General

Transocean Ltd. (“Transocean,” the “Company,” the “Group”, “we,” “us”, or “our”) is the parent company of Transocean Inc., Transocean Management Ltd., and Transocean Services AS. The statutory financial statements are of overriding importance for the purpose of the economic and financial assessment of the Company. The unconsolidated statutory financial statements of the Company are prepared in accordance with Swiss law.

The financial statements of Transocean Ltd. have been prepared in accordance with the requirements of the Swiss Code of Obligations. Transocean Ltd. is listed on the New York Stock Exchange and on the SIX Swiss Exchange, and is registered with the commercial register in the canton of Zug.

Note 2 — Summary of Significant Accounting Policies

Exchange rate differences — The Company keeps its accounting records in U.S. Dollars (“USD”) and translates them into Swiss Francs (“CHF”) for statutory reporting purposes. Assets and liabilities denominated in foreign currencies are translated into CHF using the year-end rates of exchange, except investments in affiliates and the Company’s equity (other than current-year transactions), which are translated at historical rates. Income statement transactions are translated into Swiss Francs at the average rate of the year. Exchange differences arising from business transactions and net unrealized losses are recorded in the income statement. Net unrealized gains are deferred and recorded in other current liabilities on the balance sheet.

Current assets and liabilities — Current assets and liabilities are recorded at cost less adjustments for impairment of value.

Financial assets—Financial assets are recorded at acquisition cost less adjustments for impairment of value.

Cash—Cash consists of cash in the bank.

Property and equipment — Property and equipment consists primarily of office equipment and is recorded at historical cost net of accumulated depreciation. We generally provide for depreciation under the straight-line method. The estimated original useful life of our office equipment is four years.

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TRANSOCEAN LTD.

NOTES TO STATUTORY FINANCIAL STATEMENTS - Continued

Note 3 — Investment in Affiliates

Principal indirect investments in affiliates include:

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TRANSOCEAN LTD
NOTES TO STATUTORY FINANCIAL STATEMENTS - Continued

Note 4 — Shareholders’ Equity

(in CHF thousands except share data)

(a)              The reserve for treasury shares represents the cost of treasury shares held directly by Transocean Ltd. and indirectly by Transocean Inc.  During 2012, our affiliate, Transocean Inc., purchased 269,082 treasury shares in connection with share-based compensation valued at CHF 12.2 million. During 2011, our affiliate purchased 224,121 treasury shares in connection with share-based compensation valued at CHF 15.5 million. See Note 5—Treasury Shares.

Conditional share capital — Our articles of association provide for conditional capital that allows the issuance of 167,617,649 additional registered shares without obtaining additional shareholder approval.  The conditional shares may be issued:

(1)         Through the exercise of conversion, exchange, option, warrant or similar rights for the subscription of shares granted in connection with bonds, options, warrants or other securities newly or already issued in national or international capital markets or new or already existing contractual obligations convertible into or exercisable or exchangeable for Transocean Ltd. registered shares or shares of one of its group companies or any of their respective predecessors ; or

(2)         In connection with the issuance of registered shares, options or other share-based awards to directors, employees, contractors, consultants or other persons providing services to Transocean Ltd. or one of its subsidiaries.

In connection with the issuance of bonds, notes, warrants or other financial instruments or contractual obligations convertible into or exercisable or exchangeable for Transocean Ltd. registered shares, the board of directors is authorized to withdraw or limit the advance subscription rights of shareholders in certain circumstances.

Authorized share capital — At the annual general meeting on May 13, 2011, our shareholders approved an authorized share capital in the amount of CHF 1,005,705,855, authorizing the issuance of a maximum of 67,047,057 fully paid-in shares with a par value of CHF 15 each, which expires on May 13, 2013.  On November 18, 2011, our board of directors resolved, based on our authorized share capital contained in our articles of association dated May 13, 2011, to increase our share capital through the issuance of up to 30,000,000 new, fully paid in shares.  In December 2011, we completed a public offering of 29.9 million shares at a share price of USD 40.50, equivalent to CHF 37.32 using an exchange rate of USD 1.00 to CHF 0.9215.  On December 5, 2011, we received proceeds of CHF 1.1 billion, net of underwriting discounts and commissions, estimated issuance costs and the Swiss Federal Issuance Stamp Tax.  These issuance costs totaling CHF 48 million were expensed and are included in general and administrative expenses. At December 31, 2011, the authorized share capital amounted to CHF 557,205,855, authorizing the issuance of a maximum of 37,147,057 fully paid-up shares with a par value of CHF 15 each at any time until May 13, 2013.

On May 31, 2012, we issued 8.7 million shares to Transocean Pacific Drilling Holdings Limited, for delivery to Quantum Pacific Management Limited, a third-party interest holder in Transocean Pacific Drilling Inc. (“TPDI”), in exchange for its 50%-ownership interest in TPDI. At December 31, 2012, the authorized share capital amounted to CHF 426,775,590, authorizing the issuance of a maximum 28,451,706 full paid-up shares with a par value of CHF 15 each at any time until May 13, 2013.

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TRANSOCEAN LTD
NOTES TO STATUTORY FINANCIAL STATEMENTS - Continued

Dividend distribution — In May 2011, at our annual general meeting, our shareholders approved a dividend of USD 3.16 per outstanding share, payable in four equal installments of USD 0.79 per outstanding share, subject to certain limitations.  In May 2011, we transferred CHF 1,937 million out of General Legal Reserve — Reserve from Capital Contribution to Dividend Reserve from Capital Contribution and recognized a dividend payable in the amount of approximately CHF 935 million, recorded in other current liabilities, with the corresponding entry to Dividend Reserve.  On June 15, 2011, September 21, 2011 and December 21, 2011 we paid the first three installments, in the aggregate amount of CHF 676 million, to shareholders of record as of May 20, 2011, August 26, 2011 and November 25, 2011, respectively.  At December 31, 2011, the carrying amount of the unpaid distribution payable was CHF 259 million. On March 21, 2012, we paid the fourth and final installment of CHF 253 million and transferred the remaining CHF 6.1 million back to Dividend Reserve from Capital Contribution. The aggregate amount of the Dividend Reserve from Capital Contribution that was not used for the dividend payments, i.e., CHF 1,007,793, was transferred back to General Legal Reserve - Reserve from Capital Contribution.

Note 5 — Treasury Shares

(a)         2010 share percentage is based on 335,235,298 shares issued. 2011 share percentage is based on 365,135,298 shares issued which included the 29.9 million authorized share capital increase in December 2011. 2012 share percentage is based on 373,830,649 shares issued, which includes the 8,695,351 authorized share capital increase in May 2012.

Shares held by subsidiary — In 2012 and 2011 1,004,107 and 825,115 treasury shares, respectively, were transferred to satisfy obligations under share-based compensation plans from the treasury shares issued to Transocean Inc. as part of the Redomestication Transaction in connection with obligations under share-based compensation plans.  The proceeds of the treasury share transfers in connection with exercises of options amounted to CHF 9 million and CHF 8.7 million for 2012 and 2011, respectively.  Transfers under restricted share awards schemes were at book value.

Share repurchase program — During the year ended December 31, 2010, following the authorization by our Board of Directors, we repurchased 2,863,267 of our shares under the share repurchase program for an aggregate purchase price of CHF 257 million.  There were no repurchases under this program in 2011 or 2012.  These shares have not been marked to market because they are to be cancelled.

Note 6 — Significant Shareholders

As of December 31, 2012 and 2011 we had no shareholders that, to the knowledge of the Company, were beneficial owners of more than 5% of the Company’s issued share capital.

Transocean held directly and indirectly through its affiliate, Transocean Inc., 14,315,398 and 15,319,505 treasury shares representing 3.83% and 4.20% of the issued share capital at December 31, 2012 and 2011, respectively, as outlined in Note 5 — Treasury Shares.

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TRANSOCEAN LTD.

NOTES TO STATUTORY FINANCIAL STATEMENTS - Continued

Note 7 — Board of Directors Compensation

Directors who are employees of the Company do not receive compensation for Board service.  At present, all of the directors except Steven L. Newman are non-employees and receive compensation.

We use a combination of cash and equity incentive compensation to attract and retain qualified candidates to serve on our Board.  The Corporate Governance Committee annually reviews the compensation paid to non-executive directors and makes a recommendation to the Board regarding its determinations. When making its recommendations to the Board, the Corporate Governance Committee can exercise its discretion as to the level and mix of compensation paid to the directors.  In February 2012, based upon its review of director compensation and the advice of our former compensation consultant, the Corporate Governance Committee, in exercising its discretion, concluded that the total compensation received by non-executive directors was within a competitive range relative to members of the Company’s peer group generally used for the consideration of executive compensation and that the mix of cash and equity incentive compensation was appropriate and in line with current market competitive practice and recommended no change. Based on this recommendation, the Board exercised its discretion and left the compensation levels unchanged from those paid in 2011.

Non-employee director compensation is listed in the table below:

(a)                                 Non-employee director compensation is paid in USD and did not change from 2011 to 2012.  The fees fluctuation from 2011 in the table above is due to the difference in exchange rate used for the presentation of the Swiss statutory financial statements.

(b)                                 The board meeting attendance fee is paid for those meetings that were attended in excess of the four regularly scheduled board meetings.

(c)                                  The committee meeting attendance fee is only paid for those meetings that were attended in excess of four regularly scheduled committee meetings.

Since May 2011, J. Michael Talbert has served the Company as its non-executive Chairman of the Board, in which capacity he has received a CHF 248,480 annual retainer, paid quarterly, in lieu of the annual retainer the other non-employee directors receive.  Until his retirement in May 2011, our former Chairman, Robert E. Rose, received a CHF 294,335 annual retainer, paid quarterly.  Prior to May 2011, Mr. Talbert served the Company as its non-executive Vice-Chairman of the Board, in which capacity he received a CHF 44,328 annual retainer, paid quarterly, in addition to the annual retainer the other non-employee directors received. Mr. Rose and Mr. Talbert also received the same meeting fees and the grant of deferred units to non-employee directors described above. All retainers are paid on a quarterly basis and are only paid for quarters in which the director actually served.

In addition, we pay or reimburse our directors’ travel and incidental expenses incurred for attending Board, committee and shareholder meetings and for other Company business-related purposes.

At our Board meeting held immediately after the 2012 annual general meeting of our shareholders, the Board granted 5,742 deferred units to each non-employee director equal in aggregate value to CHF 245,814 based upon the average price of the high and low sales prices of our shares for the 10 trading days immediately prior to the date of our Board meeting (calculated at CHF 42.81 per share).  The terms of the deferred units included vesting in equal installments over three years, on the first, second and third anniversaries of the date of grant, and a requirement that each director hold the vested deferred units or the shares attributable to such units until they leave the Board.  Vesting of the deferred units is not subject to any performance measures.

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TRANSOCEAN LTD.

NOTES TO STATUTORY FINANCIAL STATEMENTS - Continued

The following table summarizes the compensation of our non-employee directors for 2012:

(a)                                  Compensation for the period of Board membership from January 1, 2012 to December 31, 2012.

(b)                                  Fees earned from January 1, 2012 to December 31, 2012 include the retainer, meeting fees, and dividends earned on shares.

(c)                                   Deferred units are based on the fair value granted during the year.

(d)                                  Members of the Finance/Benefits Committee

(e)                                   Members of the Audit Committee

(f)                                    Members of Executive Compensation Committee

(g)                                   Members of Corporate Governance Committee

(h)                                  Members of Health, Safety, and Environment Committee

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TRANSOCEAN LTD.

NOTES TO STATUTORY FINANCIAL STATEMENTS - Continued

The following table summarizes the compensation of our non-employee directors for 2011:

(a)                                  Compensation for the period of Board membership from January 1, 2011 to December 31, 2011.

(b)                                  Fees earned from January 1, 2011 to December 31, 2011 include the retainer, meeting fees, and dividends earned on shares.

(c)                                   Deferred units are based on the fair value granted during the year.

(d)                                  Members of the Finance/Benefits Committee

(e)                                   Members of the Audit Committee

(f)                                    Members of Executive Compensation Committee

(g)                                   Members of Corporate Governance Committee

(h)                                  Members of Health, Safety, and Environment Committee

(i)                                      Richard Anderson resigned on June 30, 2011 and forfeited his 2011 annual deferred units totaling CHF 228,440.

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TRANSOCEAN LTD.

NOTES TO STATUTORY FINANCIAL STATEMENTS - Continued

Note 8 — Executive Management Compensation

The total compensation of the executive officers of the Company is summarized in the table below.  In accordance with its authority under the Company’s organizational regulations, the Board of Directors determined that all officers who meet the definition of officers under Section 16 of the Securities and Exchange Act of 1934, as amended, are members of the Company’s executive management (a). The table below reflects the determination by the Board of Directors of the composition of executive management.

(a)                                   The Board of Directors has determined that the officers who had assumed the responsibilities of General Counsel from October 23, 2012 until November 16, 2012 were not members of the Company’s executive management.

(b)                                   On January 5, 2012, Transocean Ltd. announced that Ricardo Rosa had stepped down as Executive Vice President and Chief Financial Officer effective January 9, 2012. Mr. Rosa subsequently retired from Transocean effective April 30, 2012. Effective January 9, 2012 until November 15, 2012 Greg L. Cauthen served as Interim Chief Financial Officer. Effective November 15, 2012, Esa Ikaheimonen joined Transocean as Executive Vice President and Chief Financial Officer.

(c)                                    On January 25, 2012, Robert Shaw notified Transocean Ltd. of his resignation as Vice President, Controller and Principal Accounting Officer. Effective immediately, Greg L. Cauthen was appointed Interim Controller and Principal Accounting Officer. On February 17, 2012 the Board of Directors appointed David Tonnel as Senior Vice President, Finance and Controller and Principal Accounting Officer, effective March 1, 2012.

(d)                                   On October 23, 2012, Transocean Ltd. announced that Nick Deeming had stepped down as Senior Vice President and General Counsel, effective immediately. Effective November 17, 2012 and until a replacement is named, Allen Katz will serve as Interim General Counsel.

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TRANSOCEAN LTD.

NOTES TO STATUTORY FINANCIAL STATEMENTS - Continued

The following tables show the gross payments (i.e. compensation before deduction of employee social insurance and pension contributions) that were made to or on behalf of the executive officers of the Company in 2012 and 2011 but excluding share-based compensation, which is shown in separate tables below. The bonus is presented on an accrual basis and the tax equalization payments to the executive officers are presented on a cash basis.

For the year 2012