Company: RIG
Filing Date: 2025-09-26
Form Type: 424B5
Source: 0001451505-25-000102
Chunk: 58

Company: Transocean Ltd.
Filing Date: 2025-09-26
Form: 424B5
Chunk 58
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 superseded, to constitute a part of this prospectus supplement. A copy of these filings will be provided upon oral or written request, other than an exhibit to these filings unless we have specifically incorporated that exhibit by reference into the filing, at no cost. You may request such copies by writing or calling: Transocean Ltd. c/o Transocean Offshore Deepwater Drilling Inc. 1414 Enclave Parkway Houston, Texas 77077 Attn: Investor Relations +1 (713) 232-7500

S-36

PROSPECTUS

<div align='center'>Transocean Ltd.

SharesWarrantsPurchase ContractsRightsUnitsGuarantees

Transocean Inc.

Debt SecuritiesWarrantsPurchase ContractsRightsUnits</div>

Transocean Ltd. or Transocean Inc. will provide the specific terms of the securities in supplements to this prospectus. The securities may be offered separately or together in any combination or as separate series. You should read this prospectus and any supplement carefully before you invest.

Transocean Ltd.’s shares are traded on the New York Stock Exchange under the trading symbol “RIG.”

Transocean Ltd.’s principal executive offices are located at Turmstrasse 30, 6312 Steinhausen, Switzerland, and its telephone number at that address is +41 (41) 749 0500. Transocean Inc.’s principal executive offices are located at 36C Dr. Roy’s Drive, Bermuda House, 4th Floor, George Town, Grand Cayman, Cayman Islands KY1-1003, and its telephone number at that address is +1 (345) 745 4500.

INVESTING IN OUR SECURITIES INVOLVES RISKS. SEE “RISK FACTORS” ON PAGE3OF THIS PROSPECTUS AND ANY SIMILAR SECTION CONTAINED IN THE APPLICABLE PROSPECTUS SUPPLEMENT AND THE DOCUMENTS THAT ARE INCORPORATED BY REFERENCE INTO THIS PROSPECTUS CONCERNING FACTORS YOU SHOULD CONSIDER BEFORE INVESTING IN OUR SECURITIES.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined whether this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

<div align='center'>The date of this prospectus is June 28, 2024.</div>

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