144/A 0001950047-25-009413 0001240666 XXXXXXXX LIVE 0001451505 Transocean Ltd. 001-38373 TURMSTRASSE 30 STEINHAUSEN V8 6312 41 41 749 0500 THIGPEN JEREMY D Director 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 Common 04/22/2017 RSU Vesting under a Registered Plan Issuer N 14493 04/22/2017 Services Rendered Common 02/06/2020 Performance Stock Units Issuer N 792 02/06/2020 Services Rendered Common 02/08/2024 Performance Stock Units Issuer N 249093 02/08/2024 Services Rendered Common 02/08/2024 Performance Stock Units Issuer N 235622 02/08/2024 Services Rendered Y 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. 12/01/2025 /s/ Jeremy D.Thigpen