Ownership Submission
FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN 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 *
Perestroika
  2. Issuer Name and Ticker or Trading Symbol
Transocean Ltd. [RIG]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
__X__ Director __X__ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
(Last)
(First)
(Middle)
TURMSTRASSE 30
3. Date of Earliest Transaction (Month/Day/Year)
06/15/2018
(Street)

STEINHAUSEN, V8 6312
4. If Amendment, Date Original Filed(Month/Day/Year)
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 Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)
2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code
(Instr. 8)
4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)
5. Amount of Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 3 and 4)
6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)
7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V Amount (A) or (D) Price
Shares               660,000 D  
Shares               32,436,351 I See footnote (1)

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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 3)
2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction Code
(Instr. 8)
5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)
6. Date Exercisable and Expiration Date
(Month/Day/Year)
7. Title and Amount of Underlying Securities
(Instr. 3 and 4)
8. Price of Derivative Security
(Instr. 5)
9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 4)
10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)
11. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares
0.5% Exchangeable Senior Bonds due 2023 (2)             01/30/2018 01/30/2023 Shares (2)   $ 355,611,000 (2) I See footnote (1)

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
Perestroika
TURMSTRASSE 30
STEINHAUSEN, V8 6312
  X   X    

Signatures

 Daniel Ro-Trock By Power of Attorney   06/15/2018
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 4(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 March 16, 2018, Perestroika AS transferred 32,436,351 of its Shares of Transocean Ltd. (the "Company") and its 0.5% Exchangeable Senior Bonds due 2023 (the "Exchangeable Bonds") to Perestroika (Cyprus) Ltd. Perestroika (Cyprus) Ltd. is a wholly owned subsidiary of Perestroika AS. Mr. Mohn is the sole owner and director of Perestroika AS and is the beneficial owner of all securities owned by Perestroika AS and Perestroika (Cyprus) Ltd. While this change in the form of Perestroika AS's indirect beneficial ownership is exempt from reporting, this Form 4 is being voluntarily filed early to report this change.
(2) The Exchangeable Bonds are issued by Transocean Inc., a wholly owned subsidiary of the Company, and fully and unconditionally guaranteed by the Company. The Exchangeable Bonds are exchangeable into Shares of the Company at an initial rate of 97.29756 Shares per $1,000 principal amount of Exchangeable Bonds, which initial rate is subject to adjustment in accordance with the Indenture, dated January 30, 2018, among Transocean Inc., the Company, Computershare Trust Company, N.A. and Computershare Trust Company of Canada. The Exchangeable Bonds are exchangeable at any time prior to and up to the maturity date of January 30, 2023.
 
Remarks:
Perestroika (Cyprus) Ltd. is a wholly owned subsidiary of Perestroika AS.  Due to Perestroika AS's designation of a member of the board of directors of the Company, Perestroika (Cyprus) Ltd. may be deemed to be a director of the Company by deputization.  Perestroika AS's right to designate a member of the Company's board of directors has since terminated.

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