Company: RIG
Filing Date: 2025-09-26
Form Type: 424B5
Source: 0001451505-25-000102
Chunk: 7

Company: Transocean Ltd.
Filing Date: 2025-09-26
Form: 424B5
Chunk 7
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 this prospectus supplement, the accompanying base prospectus, and our Annual Report on Form 10-K for the year ended December 31, 2024, our Quarterly Report on Form 10-Q for the quarterly period ended March 31, 2025 or our Quarterly Report on Form 10-Q for the quarterly period ended June 30, 2025 for a discussion of the factors you should carefully consider before making a decision to invest in our shares.                                                                                                                                                                                                                                                                                                                                                                                                                                         |

Unless otherwise indicated or the context otherwise requires, all information in this prospectus supplement reflects and assumes no exercise by the underwriters of their option to purchase up to an additional 18,750,000 shares at the public offering price, less underwriting discounts and commissions. Please read “Underwriting (Conflicts of Interest).”

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The number of shares is based upon 957,242,035 shares outstanding as of September 22, 2025 and excludes:

| ● | all shares that may be issuable upon the exchange of our $37 million outstanding aggregate principal amount of 4.0% Senior Guaranteed Exchangeable Bonds due 2025 in the event Transocean elects to settle such exchange by delivering shares, which are exchangeable at an initial implied conversion price of $5.25 per share, subject to adjustment upon the occurrence of certain events; |

| ● | all shares that may be issuable upon the exchange of our $259 million outstanding aggregate principal amount of 4.625% Senior Guaranteed Exchangeable Bonds due 2029 in the event Transocean elects to settle such exchange by delivering shares, which are exchangeable at an initial implied conversion price of $3.44 per share, subject to adjustment upon the occurrence of certain events; |

| ● | all shares that may be issuable upon the exercise of the 22.2 million warrants to purchase our shares in the event Transocean elects to settle such exchange by delivering shares, which may be exercised by holders at any time prior to the close of business on March 13, 2026 at an exercise price equal to $3.71 per share, subject to certain anti-dilutive adjustments; and |

| ● | 37,103,314 shares reserved as of August 31, 2025, for future issuance pursuant to our 2015 Long-Term Incentive Plan, as amended and restated effective May 30, 2025. |

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### RISK FACTORS
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