Company: RIG
Filing Date: 2025-09-26
Form Type: 424B5
Source: 0001451505-25-000102
Chunk: 6

Company: Transocean Ltd.
Filing Date: 2025-09-26
Form: 424B5
Chunk 6
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 deploying our high-specification fleet in a single, global market that is geographically dispersed in oil and gas exploration and development areas throughout the world. Although rigs can be moved from one region to another, the cost of moving rigs and the availability of rig-moving vessels may cause the supply and demand balance to fluctuate somewhat between regions. Still, significant variations between regions do not tend to persist long term because of rig mobility. The location of our rigs and the allocation of resources to operate, build or upgrade our rigs are determined by the activities and needs of our customers.

#### Corporate Information
We are a Swiss corporation with our registered office in Steinhausen, Canton of Zug and with our principal executive offices located at Turmstrasse 30, 6312 Steinhausen, Switzerland. Our telephone number at that address is +41 (41) 749-0500.

#### Offering Shares
Our board of directors has authorized the issuance of shares in connection with this offering on a non-preemptive basis pursuant to the capital bands set forth in our articles of association as previously approved by our shareholders. The board has determined that all prerequisites under our articles of association, the board resolutions pursuant to which the shares were initially issued into “treasury,” as well as the applicable requirements of Swiss law for the withdrawal of shareholders’ preemptive rights in respect of the shares offered hereby, have been met.

Please read “Description of Transocean Ltd. Shares—Preemptive Rights and Advance Subscription Rights.”

#### ​

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THE OFFERING

| ​                                           | ​ | ​                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
| Issuer                                      | ​ | Transocean Ltd.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| ​                                           | ​ | ​                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
| Shares offered                              | ​ | 125,000,000 shares. An affiliate of one of our directors, Frederik Mohn, has provided an indication of interest in purchasing up to an aggregate of 4,000,000 shares from the underwriters at the public offering price.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
| ​                                           | ​ | ​                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
| Option to purchase additional shares        | ​ | We have granted the underwriters an option to purchase up to an additional 18,750,000 shares at the public offering price, less underwriting discounts and commissions. The underwriters may exercise their option at any time within 30 days from the date