Ownership Submission
FORM 3
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
  Tonnel David A
2. Date of Event Requiring Statement (Month/Day/Year)
03/01/2012
3. Issuer Name and Ticker or Trading Symbol
Transocean Ltd. [RIG]
(Last)
(First)
(Middle)
4 GREENWAY PLAZA
4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
SVP, Finance & Controller
5. If Amendment, Date Original Filed(Month/Day/Year)
(Street)

HOUSTON, TX 77046
6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Beneficially Owned
1.Title of Security
(Instr. 4)
2. Amount of Securities Beneficially Owned
(Instr. 4)
3. Ownership Form: Direct (D) or Indirect (I)
(Instr. 5)
4. Nature of Indirect Beneficial Ownership
(Instr. 5)
Registered Shares 5,622
D
 
Registered Shares 987
I
By Issuer Employee Savings Plan

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly. SEC 1473 (7-02)
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Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 4)
2. Date Exercisable and Expiration Date
(Month/Day/Year)
3. Title and Amount of Securities Underlying Derivative Security
(Instr. 4)
4. Conversion or Exercise Price of Derivative Security 5. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 5)
6. Nature of Indirect Beneficial Ownership
(Instr. 5)
Date Exercisable Expiration Date Title Amount or Number of Shares
Stock Options 07/09/2009 07/08/2018 Registered Shares 3,401 $ 144.32 D  
Stock Options 09/01/2010(1) 08/31/2019 Registered Shares 2,729 $ 74.93 D  
Stock Options 02/18/2011(2) 02/17/2020 Registered Shares 11,792 $ 83.32 D  
Stock Options 02/10/2012(3) 02/09/2021 Registered Shares 8,731 $ 78.76 D  
Stock Options 02/17/2013(4) 02/16/2022 Registered Shares 22,999 $ 50.79 D  
Deferred Units   (5)   (5) Registered Shares 529 $ (5) D  
Deferred Units   (6)   (6) Registered Shares 5,229 $ (6) D  
Deferred Units   (7)   (7) Registered Shares 2,959 $ (7) D  
Deferred Units   (8)   (8) Registered Shares 9,442 $ (8) D  

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
Tonnel David A
4 GREENWAY PLAZA
HOUSTON, TX 77046
      SVP, Finance & Controller  

Signatures

Eric J. Christ by Power of Attorney 03/02/2012
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 5(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) On September 1, 2009, the reporting person was awarded 2,729 stock options which vest as follows: 909 on September 1, 2010; 910 on September 1, 2011; and 910 on September 1, 2012.
(2) On February 18, 2010, the reporting person was awarded 11,792 stock options which vest as follows: 3,930 on February 18, 2011; 3,931 on February 18, 2012; and 3,931 on February 18, 2013.
(3) On February 10, 2011, the reporting person was awarded 8,731 stock options which vest as follows: 2,910 on February 10, 2012; 2,910 on February 10, 2013; and 2,911 on February 10, 2014.
(4) On February 17, 2012, the reporting person was awarded 22,999 stock options which vest as follows: 7,666 on February 17, 2013; 7,666 on February 17, 2014; and 7,667 on February 17, 2015.
(5) Deferred Units, which are 1-for-1 share equivalents, were acquired on September 1, 2009 pursuant to the Issuer's long-term incentive plan. Outstanding deferred units vest as follows: 529 shares on September 1, 2012.
(6) Deferred Units, which are 1-for-1 share equivalents, were acquired on November 17, 2010, pursuant to the Issuer's long-term incentive plan. Outstanding deferred units vest as follows: 2,614 shares on November 17, 2012 and 2,615 shares on November 17, 2013.
(7) Deferred Units, which are 1-for-1 share equivalents, were acquired on February 10, 2011, pursuant to the Issuer's long-term incentive plan. Outstanding deferred units vest as follows: 1,479 shares on February 10, 2013 and 1,480 shares on February 10, 2014.
(8) Deferred Units, which are 1-for-1 share equivalents, were granted on March 1, 2012, pursuant to the Issuer's long-term incentive plan and will vest as follows: 3,147 on March 1, 2013; 3,147 on March 1, 2014; and 3,148 on March 1, 2015.

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