Company: RIG
Filing Date: 2025-09-24
Form Type: 424B5
Source: 0001451505-25-000097
Chunk: 11

Company: Transocean Ltd.
Filing Date: 2025-09-24
Form: 424B5
Chunk 11
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 of stock in this offering) and other sales or exchanges of our stock could trigger an ownership change and, thus, a limitation on our subsidiaries’ ability to utilize NOL carryforwards under Section 382. Such limitation could result in an increase in our subsidiaries’ U.S. federal income tax liability.**

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### USE OF PROCEEDS
We estimate that the net proceeds from the sale of our shares in this offering will be approximately $ million (or approximately $ million if the underwriters exercise in full their option to purchase additional shares), after deducting discounts and commissions payable to the underwriters as well as our expenses related to this offering. The Company intends to use the net proceeds from the offering for the repayment or redemption of indebtedness, including the repayment or redemption of a portion of the $655 million aggregate principal amount of the 8.00% Senior Notes due February 2027 issued by Transocean International Limited, a wholly owned subsidiary of the Company, to the extent such principal is not otherwise refinanced, repaid or redeemed. Any proceeds from the offering that are not used promptly for such purposes will be used for general corporate purposes.

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#### DESCRIPTION OF TRANSOCEAN LTD. SHARES
The following description of the share capital of Transocean Ltd. is a summary. This summary is subject to the complete text of our articles of association, which are incorporated by reference into the registration statement of which this prospectus forms a part. We encourage you to read the articles of association carefully. In this section, references to “we,” “our,” “us,” and “Transocean” mean Transocean Ltd.

General

Issued Share Capital.As of September 22, 2025, the share capital of Transocean registered shares in the commercial register, which reflects Transocean’s total issued share capital, was USD 120,400,968.10, divided into 1,204,009,681 registered shares, par value USD 0.10 per share. The issued Transocean shares are fully paid, non-assessable, and rank pari passu with each other and all other Transocean shares.

Capital Band (Capital Authorization).Article 5 of our articles of association provided for a general capital band ranging from USD 99,984,390.10 (lower limit) to USD 120,400,968.10 (upper limit), which could be used by