144/A: Issuer Information

Name of Issuer

Transocean Ltd.

SEC File Number

001-38373

Address of Issuer

TURMSTRASSE 30
STEINHAUSEN
SWITZERLAND
6312

Phone

41 41 749 0500

Name of Person for Whose Account the Securities are To Be Sold

THIGPEN JEREMY D

See the definition of "person" in paragraph (a) of Rule 144. Information is to be given not only as to the person for whose account the securities are to be sold but also as to all other persons included in that definition. In addition, information shall be given as to sales by all persons whose sales are required by paragraph (e) of Rule 144 to be aggregated with sales for the account of the person filing this notice.

Relationship to Issuer

Director

144/A: Securities Information

Title of the Class of Securities To Be Sold

Name and Address of the Broker

Number of Shares or Other Units To Be Sold

Aggregate Market Value

Number of Shares or Other Units Outstanding

Approximate Date of Sale

Name the Securities Exchange

Common

Morgan Stanley Smith Barney LLC Executive Financial Services
1 New York Plaza 8th Floor
New York NY 10004

500000

2159400.00

1101441205

11/26/2025

NYSE

Furnish the following information with respect to the acquisition of the securities to be sold and with respect to the payment of all or any part of the purchase price or other consideration therefor:

144/A: Securities To Be Sold

Title of the Class

Date you Acquired

Nature of Acquisition Transaction

Name of Person from Whom Acquired

Is this a Gift?

Date Donor Acquired

Amount of Securities Acquired

Date of Payment

Nature of Payment *

Common

04/22/2017

RSU Vesting under a Registered Plan

Issuer

14493

04/22/2017

Services Rendered

Common

02/06/2020

Performance Stock Units

Issuer

792

02/06/2020

Services Rendered

Common

02/08/2024

Performance Stock Units

Issuer

249093

02/08/2024

Services Rendered

Common

02/08/2024

Performance Stock Units

Issuer

235622

02/08/2024

Services Rendered

* If the securities were purchased and full payment therefor was not made in cash at the time of purchase, explain in the table or in a note thereto the nature of the consideration given. If the consideration consisted of any note or other obligation, or if payment was made in installments describe the arrangement and state when the note or other obligation was discharged in full or the last installment paid.

Furnish the following information as to all securities of the issuer sold during the past 3 months by the person for whose account the securities are to be sold.

144/A: Securities Sold During The Past 3 Months

Nothing to Report

144/A: Remarks and Signature

Remarks

This amendment is being filed due to an administrative error with respect to the Form 144 filed on November 26, 2025. This amendment corrects the number of shares sold from 499,940 shares to 500,000 shares.

Date of Notice

12/01/2025

ATTENTION:

The person for whose account the securities to which this notice relates are to be sold hereby represents by signing this notice that he does not know any material adverse information in regard to the current and prospective operations of the Issuer of the securities to be sold which has not been publicly disclosed. If such person has adopted a written trading plan or given trading instructions to satisfy Rule 10b5-1 under the Exchange Act, by signing the form and indicating the date that the plan was adopted or the instruction given, that person makes such representation as of the plan adoption or instruction date.

Signature

/s/ Jeremy D.Thigpen

144/A: Filer Information

Submission Contact Information

144/A: Issuer Information

144/A: Securities Information

144/A: Securities To Be Sold

144/A: Securities Sold During The Past 3 Months

144/A: Remarks and Signature

ATTENTION:

ATTENTION: Intentional misstatements or omission of facts constitute Federal Criminal Violations (See 18 U.S.C. 1001)