Transocean LTD : . Provides Fleet Update Summary

ZUG, SWITZERLAND--(Marketwire - March 15, 2012) - Transocean Ltd. (NYSE: RIG:
http://marketwire.com/news_room/stock?ticker=RIG) (SIX: RIGN) today issued a monthly fleet update summary which includes newly signed contracts, significant changes to existing contracts, and changes in estimated planned out of service time of 15 days or longer for all rig classifications since the previously issued comprehensive fleet status report or fleet update summary. Significant highlights include the following:

• Deepwater Expedition - Awarded a two-year contract with an undisclosed customer commencing December 2012 at an initial dayrate of $650,000 ($475 million contract backlog). Additionally, the contract includes three priced eight-month option periods.
• Discoverer Seven Seas - Awarded a three-well contract (approximately 180 days) for work offshore Indonesia at a dayrate of $445,000 ($80 million contract backlog). The rig's prior dayrate was $295,000.
• GSF Arctic III - Awarded a three-month contract extension in the U.K. sector of the North Sea at a dayrate of $315,000 ($28 million contract backlog). The rig's prior dayrate was $280,000.
• Planned 2012 out of service time increased by a net 284 days, including 140 days associated with preparing the Deepwater Expedition, Discoverer Seven Seas, and Trident XIV for new or anticipated contracts.
• As previously disclosed, the Deepwater Millennium and the GSF Grand Banks shipyards were completed and the rigs are currently operating. In addition, since the previous fleet update summary, the GSF Rig 140 has left the shipyard and is en route to India.

The fleet update summary can be accessed at www.deepwater.com:
http://www.deepwater.com/ by clicking on the Fleet Status Report link found in the toolbar.

Forward-Looking Statements

Statements regarding the estimated duration of customer contracts, contract dayrate amounts, future contract commencement dates and locations, planned shipyard projects and other out of service time, as well as any other statements that are not historical facts in the report, are forward-looking statements that involve certain risks, uncertainties and assumptions. These include but are not limited to operating hazards and delays, risks associated with international operations, actions by customers and other third parties, the future prices of oil and gas and other factors detailed in the company's most recent Form 10-K and other filings with the Securities and Exchange Commission. Should one or more of these risks or uncertainties materialize, or should underlying assumptions prove incorrect, actual results may vary materially from those indicated.

About Transocean

Transocean is a leading international provider of offshore contract drilling services for oil and gas wells. Transocean owns or has partial ownership interests in and operates a fleet of 132 mobile offshore drilling units consisting of 50 High-Specification Floaters (Ultra-Deepwater, Deepwater and Harsh-Environment semisubmersibles and drillships), 25 Midwater Floaters, nine High-Specification Jackups, 47 Standard Jackups and one swamp barge. In addition, we have two Ultra-Deepwater Drillships and four High-Specification Jackups under construction. Transocean specializes in technically demanding sectors of the global offshore drilling business with a particular focus on deepwater and harsh environment drilling services. We believe we operate one of the most versatile offshore drilling fleets in the world.

For more information about Transocean, please visit the website at www.deepwater.com:
http://www.deepwater.com/.

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