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QUESTIONS AND ANSWERS ABOUT THE MERGER AND THE SPECIAL MEETING

Set forth below are questions that you, as a common unitholder of Transocean Partners, may have regarding the merger and the special meeting, and brief answers to those questions. You are urged to read carefully this proxy statement/prospectus and the other documents referred to in this proxy statement/prospectus in their entirety, including the merger agreement, which is attached as Annex A to this proxy statement/prospectus, and the documents incorporated by reference into this proxy statement/prospectus, because this section may not provide all of the information that is important to you with respect to the merger and the special meeting. The documents incorporated by reference into this proxy statement/prospectus are listed in the section titled “Where You Can Find More Information.”

Q.      What is the proposed transaction and why am I receiving this proxy statement/prospectus?

A.      Transocean and Transocean Partners have agreed to combine by merging Merger Sub, a recently formed subsidiary of Transocean, with and into Transocean Partners under the terms of the merger agreement that is described in this proxy statement/prospectus and attached as Annex A.  You are receiving this proxy statement/prospectus because the merger cannot be completed without the approval of the Transocean Partners common unitholders.

This proxy statement/prospectus serves as the proxy statement through which Transocean Partners will solicit proxies to obtain the necessary common unitholder approval for the merger and the merger agreement. It also serves as the prospectus by which Transocean will issue shares constituting the merger consideration.

This document contains important information about the merger, the merger agreement and the special meeting, and you should read it carefully. The voting materials allow you to submit your proxy and cause your common units to be voted without attending the special meeting.

Q.      Who is soliciting my proxy?

A.      Your proxy is being solicited by Transocean Partners.

Q.      Why are Transocean and Transocean Partners proposing the merger?

A.      Transocean and Transocean Partners believe that the merger will benefit Transocean Partners common unitholders and Transocean shareholders.  See “The Merger—Transocean’s Reasons for the Merger” and “The Merger—Transocean Partners Conflicts Committee and Transocean Partners Board Reasons for the Merger.”

Q.      What will Transocean Partners common unitholders receive in the merger?

A.      If the merger is completed, each outstanding Transocean Partners common unit not owned by Transocean or its subsidiaries will be converted into the right to receive 1.1427 Transocean shares (such consideration, the “Merger Consideration” and such ratio, the “Exchange Ratio”). Based on the closing price of Transocean shares on July 29, 2016, the last trading day before the public announcement of the merger, the aggregate value of the Merger Consideration was approximately $250 million.  We estimate, based upon such closing price and the number of outstanding Transocean shares and Transocean Partners common units as of such date, that, as a result of the merger, the public common unitholders of Transocean Partners immediately prior to the merger will hold approximately 5.8 percent of the aggregate number of Transocean shares outstanding immediately after the merger.  The Exchange Ratio is fixed and will not be adjusted on account of any change in price of either Transocean shares or Transocean Partners common units prior to completion of the merger.  If the Exchange Ratio would result in a Transocean Partners common unitholder being entitled to receive a fraction of a Transocean share, such fractional interest will be rounded up to the nearest whole Transocean share.  However, with respect to common units held in street name, DTC participants will not be required to round up fractional share and such participants may make certain adjustments to account for fractional shares, which could result in the payment of cash in lieu of such fractional shares.

Q.      Where will the Transocean shares and Transocean Partners common units be traded after the merger?

A.      Transocean shares will continue to trade on the New York Stock Exchange under the ticker symbol “RIG.” Transocean Partners common units will no longer be publicly traded after the completion of the merger.

Q.      What happens to the third quarter and other distributions of former Transocean Partners common unitholders?

A.      Once the merger is completed and Transocean Partners common units are exchanged for Transocean shares, when and if distributions are approved by Transocean’s shareholders and paid by Transocean, former Transocean Partners common unitholders who become and remain Transocean shareholders will receive distributions on the Transocean shares they receive in the merger in accordance with Transocean’s then current distribution policy. Transocean has not paid any distributions on Transocean shares since September 2015 and provides no assurance as to whether it will pay any distributions in the future.  Transocean Partners common unitholders will receive distributions on their Transocean Partners common units for the quarter ended June 30, 2016 and for any future quarter for which the record date with respect to a distribution approved by the board of directors or Transocean Partners (the “Transocean Partners Board”) in accordance with the terms of the merger agreement occurs prior to the effective time of the merger. Under the merger agreement, the parties have agreed to coordinate the timing of the closing of the merger to facilitate the payment of the regular quarterly cash distribution on the Transocean Partners common units for the quarter ending September 30, 2016, the record date for which will occur prior to the closing of the merger.  See “Summary—Comparative Per Share and Per Unit Market Price and Dividend Information.”

As soon as practicable after September 30, 2016, the Transocean Partners Board will determine and declare the regular quarterly distribution for the third quarter of 2016 in accordance with its limited liability company agreement and the merger agreement; provided, however, that such distribution will not be less than $0.3625 per Transocean Partners common unit without the separate determination and approval of the conflicts committee of the Transocean Partners Board (the “Transocean Partners Conflicts Committee”).

Q.      When and where will be the Transocean Partners special meeting be held?

A.      The Transocean Partners special meeting will be held at 40 George Street, 4th Floor, London, England W1U 7DW, United Kingdom.

Q.      Who is entitled to vote at the Transocean Partners special meeting?

A.      Holders of Transocean Partners common units as of the close of business on September 22, 2016, the record date, will be entitled to vote at the special meeting.

Q.      What will constitute a quorum at the special meeting?

A.      Pursuant to the Transocean Partners limited liability company agreement, a quorum for the special meeting will be constituted by the presence in person or by proxy at the special meeting of holders of the same number of Transocean Partners common units needed to approve the merger and the merger agreement, which is a number of outstanding Transocean Partners common units equal to or exceeding the sum of:

Under the above calculation, as of the record date, presence in person or by proxy of the holders of a total of 31,084,637 outstanding common units will constitute a quorum. As of the record date, there were 40,914,962 common units outstanding, of which 21,254,310 were owned by Transocean Holdings. Transocean Holdings has agreed to vote all of its common units “FOR” the merger and the merger agreement. Therefore, the presence in

person or by proxy of holders of an additional 9,830,327 common units, or approximately 50.1% of the outstanding common units not owned by Transocean Holdings, will be necessary for a quorum. Abstentions are counted for the purpose of determining the presence of a quorum. Broker non-votes will not be counted as represented in person or by proxy at the special meeting for the purpose of determining the presence of a quorum.

Q.      What is the vote required to approve the merger and the merger agreement?

A.      Approval of the merger and the merger agreement requires the affirmative vote of a unit majority.  Under the definition of unit majority, as of the record date, the holders of a total of 31,084,637 outstanding common units will be required to approve the merger and the merger agreement. As of the record date, there were 40,914,962 common units outstanding, of which 21,254,310 were owned by Transocean Holdings. Transocean Holdings has agreed to vote all of its common units “FOR” the merger and the merger agreement. Therefore, the affirmative vote of the holders of an additional 9,830,327 outstanding common units, or approximately 50.1% of the outstanding common units not owned by Transocean Holdings, is required to approve the proposal.

Abstentions, failures to vote and broker non-votes will have the same effect as votes against the merger proposal.

The affirmative vote of holders of at least a majority of the outstanding subordinated units and the approval of Transocean Holdings, in its capacity as the Transocean Member (as defined in Transocean Partners’ limited liability company agreement), is also required to approve the merger and the merger agreement.  Transocean Holdings owns all of the outstanding subordinated units and has voted those units to approve the merger agreement and the merger.  Transocean Holdings, in its capacity as the Transocean Member, has also approved the merger agreement and the merger.

Q.      Does my vote matter?

A.      Yes, your vote is very important. We encourage you to vote as soon as possible.

The merger cannot be completed unless the holders of at least a unit majority vote to approve the merger and the merger agreement.  Transocean does not own enough common units to approve the merger and the merger agreement. 

If you fail to submit a proxy or vote in person at the special meeting, or vote to abstain, or you do not provide your broker, bank or other nominee with instructions, as applicable, this will have the same effect as a vote “AGAINST” the proposal to approve the merger and the merger agreement.

Q.      What vote does the Transocean Partners Board and Transocean Partners Conflicts Committee recommend?

A.      The Transocean Partners Board and the Transocean Partners Conflicts Committee unanimously recommend that Transocean Partners common unitholders vote “FOR” the approval of the merger and the merger agreement.

On July 31, 2016, the Transocean Partners Conflicts Committee determined unanimously that the merger agreement and the transactions contemplated thereby, including the merger, are fair and reasonable to and in the best interest of Transocean Partners common unitholders not affiliated with Transocean, and Transocean ‎Partners and its subsidiaries, approved the merger agreement and the transactions contemplated thereby, including the merger, and recommended that the merger and the merger agreement be approved by the Transocean Partners common unitholders.  Also on July 31, 2016, the Transocean Partners Board determined unanimously that ‎the merger agreement and the transactions contemplated thereby, including the merger, are fair ‎and reasonable to and in the best interest of the members of Transocean Partners (including the Transocean Partners common unitholders) and Transocean ‎Partners and its subsidiaries, approved the merger agreement and the transactions contemplated thereby, including the merger, and recommended that the merger and the merger agreement be approved by Transocean Partners common unitholders.‎

For more information regarding the recommendation of the Transocean Partners Conflicts Committee and the Transocean Partners Board, see “The Merger—Recommendation of the Transocean Partners Conflicts Committee and Transocean Partners Board.”

Some directors and the executive officer of Transocean Partners may have interests in the merger that are different from, or in addition to, the interests they may have as Transocean Partners common unitholders.  See “The Merger—Interests of Directors and the Executive Officer of Transocean Partners in the Merger.”

Q.      How do Transocean and the directors and the executive officer of Transocean Partners intend to vote?

A.      As of September 22, 2016, the record date, Transocean and its subsidiaries held and were entitled to vote, in the aggregate, 21,254,310 Transocean Partners common units, representing approximately 52.0% of the outstanding Transocean Partners common units.  The directors and the executive officer of Transocean Partners held and were entitled to vote, in the aggregate, Transocean Partners common units representing less than one percent of the outstanding Transocean Partners common units.  We believe that the directors and the executive officer of Transocean Partners intend to vote all of their Transocean Partners common units “FOR” the proposal to approve the merger agreement and the merger.  Pursuant to the merger agreement, each of Transocean and Transocean Holdings has agreed to vote the Transocean Partners common units owned by it or any of its subsidiaries “FOR” the proposal to approve the merger agreement and the merger.  Accordingly, we believe approximately 21,267,147 of the outstanding Transocean Partners common units will be voted “FOR” the merger proposal by Transocean and its subsidiaries and the directors and the executive officer of Transocean Partners.

Q.      When do you expect the merger to be completed?

A.      We currently expect the merger to close in the fourth quarter of 2016.  Pursuant to the merger agreement, the parties have agreed to coordinate the timing of the closing of the merger to facilitate the payment of the regular quarterly distribution on the Transocean Partners common units for the quarter ending September 30, 2016, the record date for which will be prior to the closing of the merger.  A number of conditions must be satisfied before Transocean and Transocean Partners can complete the merger, including the approval of the merger agreement and the merger by the Transocean Partners common unitholders.  Although Transocean and Transocean Partners cannot be sure when or if all of the conditions to the merger will be satisfied, Transocean and Transocean Partners expect to complete the merger as soon as practicable following the Transocean Partners special meeting (assuming the proposal to approve the merger agreement and the merger is approved by the Transocean Partners common unitholders), which will be held on [     ], 2016. See “The Merger Agreement—Conditions to Completion of the Merger” and “Risk Factors—Risks Relating to the Merger—Failure to complete, or delays in completing, the merger could negatively impact the market price of Transocean shares and Transocean Partners common units and financial results of Transocean and Transocean Partners.”

Q.      Is completion of the merger contingent upon approval by holders of Transocean shares?

A.      No.  A vote of holders of Transocean’s shares is not required to complete the merger.

Q.      What happens if I sell my Transocean Partners common units after the record date for the special meeting but before the date of the special meeting?

A.      If you transfer your Transocean Partners common units after the record date for the special meeting but before the date of the special meeting, you will retain your right to vote at the special meeting, but you will not have the right to receive the merger consideration.  In order to receive the merger consideration, you must hold your Transocean Partners common units through the completion of the merger.

Q.      What do I need to do to vote if I hold my common units in my own name?

A.      You must be present, or represented by proxy, at the special meeting in order to vote your units. Because many common unitholders are unable to attend the special meeting in person, you may submit your proxy in the following ways:

If you plan to attend the special meeting in person and need directions to the meeting site, please contact Transocean Partners at: info@deepwater.com.

If your common units are held by a broker, bank or other nominee, you will receive from that nominee a voting instructions form to vote your common units. Your broker, bank or other nominee may permit you to provide voting instructions by telephone or by Internet.

Q.      If my common units are held in “street name” by my broker, will my broker vote my common units for me without my instructions?

A.      We recommend that you contact your broker.  Your broker can give you directions on how to instruct the broker to vote your common units.  Your broker will not be able to vote your common units unless the broker receives appropriate instructions from you.  If your common units are held by a broker, bank or other nominee, you will receive from that broker, bank or nominee a voting instructions form to vote your common units.  Your broker, bank or other nominee may permit you to provide voting instructions by telephone or by Internet. Under NYSE rules, the proposal to approve the merger and the merger agreement is not considered a routine matter for which the broker, bank or other nominee would have discretionary authority.  Therefore, if you do not instruct your broker, bank or other nominee how to vote, your broker, bank or other nominee cannot vote your common units, which will have the same effect as a vote against the merger and the merger agreement.  You are urged to respond to your broker, bank or other nominee so that your common units will be voted.

Q.      What if I do not vote?

A.      If you do not vote in person or by proxy or if you abstain from voting, or a broker non-vote is made, it will have the same effect as a vote “AGAINST” the proposal to approve the merger agreement and the merger for purposes of the vote required under Transocean Partners’ limited liability company agreement. If you sign and return your proxy card but do not indicate how you want to vote, your proxy will be counted as a vote “FOR” the merger proposal.

Q.      What should I do if I want to change my vote?

A.      If you are a common unitholder of record, you may change or revoke your proxy instructions at any time before the special meeting by:

If you hold your common units through a broker, bank or other nominee, you should contact your broker, bank or other nominee for instructions on how to change or revoke your proxy instructions.

Q.      What if I plan to attend the special meeting in person?

A.      We recommend that you submit your proxy anyway.  If you are a holder of record, you may still attend the special meeting and vote in person. Your common units will not be voted if you do not submit your proxy or do not vote in person at the special meeting.

Q.      What should I do if I receive more than one set of voting materials for the special meeting?

A.      You may receive more than one set of voting materials for the special meeting of Transocean Partners and the materials may include multiple proxy cards or voting instruction cards. For example, you will receive a separate voting instruction card for each brokerage account in which you hold common units. If you are a holder of record registered in more than one name, you will receive more than one proxy card. Please complete, sign, date and return each proxy card and voting instruction card that you receive according to the instructions on it.

Q.      What are the U.S. federal income tax consequences of the merger?

A.      Except in certain circumstances described in “The Merger—Material U.S. Federal Income Tax Consequences,” a  U.S. Holder (as defined below) generally will not recognize any gain or loss for U.S. federal income tax purposes upon the exchange of Transocean Partners common units for Transocean shares in the merger.  A Non-U.S. Holder (as defined below) generally will not recognize any gain or loss for U.S. federal income tax purposes upon the exchange of Transocean Partners common units for Transocean shares in the merger.

Please refer to “The Merger—Material U.S. Federal Income Tax Consequences” beginning on page [   ] of this proxy statement/prospectus for a description of the material U.S. federal income tax consequences of the merger.  Determining the actual tax consequences of the merger to you may be complex and will depend on your specific situation.  You should consult your tax advisor for a full understanding of the tax consequences of the merger to you.

Q.      Do Transocean Partners common unitholders have appraisal rights?

A.      Under applicable law and Transocean Partners’ limited liability company agreement, common unitholders of Transocean Partners do not have any right to receive an appraisal of the value of their common units in connection with the merger.

Q.      Are there any risks in the merger that I should consider?

A.      Yes. There are risks associated with all business combinations, including the merger.  These risks are discussed in more detail in the section “Risk Factors.”

Q.      Whom do I call if I have questions about the special meeting or the merger?

A.      You should contact one of the following:

Corporate Secretary
Transocean Partners LLC
40 George Street
London, England, W1U 7DW
United Kingdom
Phone:  +44 (20) 3675-8410

the proxy solicitor:

Innisfree M&A Incorporated
501 Madison Avenue, 20th Floor
New York, New York 10022
(888) 750-5834 (toll free from U.S. and Canada)
+(412) 232-3651 (from other countries)

SUMMARY

This summary highlights selected information from this proxy statement/prospectus. You are urged to read carefully the entire proxy statement/prospectus and the other documents referred to in this proxy statement/prospectus to understand fully the merger agreement and the merger and for a more complete description of the terms of the merger agreement.  A copy of the merger agreement is attached as Annex A to this proxy statement/prospectus and is incorporated by reference into this proxy statement/prospectus.  See “Where You Can Find More Information.” Where appropriate, the items in this summary refer to the page of this proxy statement/prospectus on which the applicable subject is discussed in more detail. This proxy statement/prospectus refers to Transocean Ltd. as “Transocean,” and Transocean Partners LLC as “Transocean Partners.” Unless the context indicates otherwise, “Transocean” means Transocean Ltd. and its subsidiaries (other than Transocean Partners) and “Transocean Partners” means Transocean Partners LLC and its subsidiaries.

The Companies

Transocean Ltd.
10 Chemin de Blandonnet
Vernier, Switzerland 1214
Phone: +41 (22) 930-9000

Transocean is a leading international provider of offshore contract drilling services for oil and gas wells.  As of September 20, 2016, Transocean owned or had partial ownership interests in and operated 58 mobile offshore drilling units, including 29 ultra-deepwater floaters, seven harsh environment floaters, four deepwater floaters, eight midwater floaters, and 10 high-specification jackups.  At September 20, 2016, Transocean also had five ultra-deepwater drillships and five high-specification jackups under construction or under contract to be constructed.

Transocean provides contract drilling services in a single, global operating segment, which involves contracting its mobile offshore drilling fleet, related equipment and work crews primarily on a dayrate basis to drill oil and gas wells.  Transocean specializes in technically demanding regions of the offshore drilling business with a particular focus on deepwater and harsh environment drilling services.  Transocean believes its drilling fleet is one of the most versatile fleets in the world, consisting of floaters and high‑specification jackups used in support of offshore drilling activities and offshore support services on a worldwide basis.

Transocean’s contract drilling services operations are 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.  Transocean’s fleet operates in a single, global market for the provision of contract drilling services.  The location of Transocean’s rigs and the allocation of resources to operate, build or upgrade its rigs are determined by the activities and needs of its customers.

For further information on Transocean, see “Business of Transocean” on page [   ].

Transocean Partners LLC
40 George Street
London, England, W1U 7DW
United Kingdom
Phone:  +44 (20) 3675-8410

Transocean Partners is a limited liability company formed by Transocean to own, operate and acquire modern, technologically advanced offshore drilling rigs.  The drilling units in Transocean Partners’ fleet are the ultra‑deepwater drillships Discoverer Inspiration and Discoverer Clear Leader and the ultra‑deepwater semisubmersible Development Driller III, which are located in the United States (“U.S.”) Gulf of Mexico.  Transocean Partners generates revenues through contract drilling services.

Transocean Partners owns a 51 percent interest in each of the entities that owns and/or operates the drilling units in its fleet (each individually, a “RigCo”, and collectively, the “RigCos”).  Transocean Holdings, an indirect wholly owned subsidiary of Transocean, owns the remaining 49 percent noncontrolling interest in each of the RigCos.  Transocean Partners controls each RigCo through its ownership of the majority of each RigCo’s shares or limited liability company interests.  Transocean Partners is entitled to only 51 percent of the RigCos’ distributions, if any.  Transocean Partners’ interest in the RigCos represents its only cash‑generating asset.  Transocean Partners depends on Transocean affiliates to operate its drilling units, manage its customer relationships, renew existing and obtain new drilling contracts and to perform other administrative support activities.

For further information on Transocean Partners, see “Business of Transocean Partners” on page [   ].

Transocean Partners Holdings Limited
70 Harbour Drive, Floor 4
P.O. Box 10342
George Town, Grand Cayman
Cayman Islands, KY-1003
Phone: (345)-745-4500

Transocean Holdings is an indirect wholly owned subsidiary of Transocean that holds common units, subordinated units and incentive distribution rights of Transocean Partners and, as the Transocean Member (as such term is defined in Transocean Partners’ limited liability company agreement), the Transocean Member Interest. Transocean Holdings also holds a 49 percent noncontrolling interest in each RigCo.

TPHL Holdings LLC
Deepwater House
Kingswells Causeway
Prime Four Business Park
Aberdeen AB15 8PU
Scotland, U.K.
Phone: +44 20 3675 8410

Merger Sub is a direct wholly owned subsidiary of Transocean Holdings recently formed for the sole purpose of effecting the merger.

Relationship of Transocean and Transocean Partners (page [  ])

Transocean formed Transocean Partners in 2014 and following Transocean Partners’ initial public offering, which closed on August 5, 2014, Transocean retained a significant interest in Transocean Partners through its indirect ownership of common and subordinated units, representing an aggregate 71.3 percent limited liability company interest in Transocean Partners, as of September 20, 2016, and all of the Transocean Partners incentive distribution rights. These interests are wholly owned by a subsidiary of Transocean, Transocean Holdings, which also holds the Transocean Member Interest in Transocean Partners, a non-economic interest that includes the right to appoint three of the seven members of the Transocean Partners Board.

Transocean Partners entered into various agreements with Transocean in relation to its initial public offering on August 5, 2014, including an omnibus agreement, master services agreements and support and secondment agreements.  These agreements were not the result of arm’s-length negotiations and neither the agreements nor any of the transactions that they provide for were effected on terms at least as favorable to the parties to these agreements as they could have obtained from unaffiliated third parties.  See “Relationship of the Parties to the Merger” for more information on these agreements and related transactions.

The Merger (page [  ])

Subject to the terms and conditions of the merger agreement and in accordance with Marshall Islands law, the merger agreement provides for the merger of Transocean Partners with Merger Sub. Transocean Partners will survive the merger and become a wholly owned subsidiary of Transocean Holdings. Upon completion of the merger, Transocean will have indirectly acquired all of the outstanding interests in Transocean Partners that it does not already own, and the Transocean Partners common units will cease to be publicly traded.

The Merger Agreement (page [  ])

Transocean, Transocean Holdings, Merger Sub and Transocean Partners have entered into an Agreement and Plan of Merger dated as of July 31, 2016, which, as it may be amended from time to time, we refer to as the merger agreement.  Pursuant to the terms and subject to the conditions of the merger agreement, at the effective time of the merger, Merger Sub will merge with and into Transocean Partners, with Transocean Partners surviving the merger. Transocean Partners as the surviving entity of the merger is sometimes referred to as the surviving entity. Upon completion of the merger, Transocean Partners will be an indirect wholly owned subsidiary of Transocean, and Transocean Partners’ common units will no longer be publicly traded.  You should read the entire merger agreement carefully before making any decisions regarding the merger, including approval of the merger and the merger agreement, because it is the legal document that governs the merger.

The Merger Consideration (page [  ])

At the effective time of the merger, each Transocean Partners common unit issued and outstanding will be converted into the right to receive 1.1427 Transocean shares, other than the Transocean Partners common units that are held by Transocean Partners, Transocean, Transocean Holdings or Merger Sub or by any subsidiary of Transocean immediately prior to the effective time, which will remain outstanding as limited liability company interests in Transocean Partners, unaffected by the merger.

Transocean will not issue any fractional shares in the merger. Instead all fractional Transocean shares that a Transocean Partners common unitholder would otherwise be entitled to receive will be aggregated and then, if a fractional share results from that aggregation, will be rounded up to the nearest whole share of Transocean.  However, with respect to common units held in street name, DTC participants will not be required to round up fractional shares and such participants may make certain adjustments to account for fractional shares, which could result in the payment of cash in lieu of such fractional shares.

Because the Exchange Ratio was fixed at the time the merger agreement was executed and because the market value of Transocean shares and Transocean Partners common units will fluctuate during the pendency of the merger, Transocean Partners common unitholders cannot be sure of the value of the merger consideration they receive relative to the value of the Transocean Partners common units that they are exchanging.  See “Risk Factors—Risks Relating to the Merger—The value of the Transocean shares to be received in the merger will fluctuate.”

Treatment of Subordinated Units, Transocean Member Interest and Incentive Distribution Rights (page [  ])

The Transocean Partners subordinated units, the Transocean Member Interest and the Transocean Partners incentive distribution rights will all remain outstanding as membership interests in Transocean Partners, unaffected by the merger.

Treatment of Transocean Partners Equity Awards (page [  ])

Generally, immediately prior to the effective time, each outstanding Transocean Partners phantom award that is subject to time-based vesting conditions and each Transocean Partners phantom award granted prior to January 1, 2016 that is subject to performance-based vesting conditions will become fully vested, and each holder of such phantom units will receive, immediately prior to the effective time, a number of Transocean Partners common units as determined in accordance with the terms of the Transocean Partners long-term incentive plan and applicable award agreement.  In

addition, immediately prior to the effective time, each outstanding Transocean Partners phantom unit granted on or after January 1, 2016 that is subject to performance-based vesting conditions will become vested at the target level, and each holder of such phantom units will receive, immediately prior to the effective time, such number of Transocean Partners common units. Such common units received will be treated, at the effective time, the same as all other Transocean Partners common units.

In certain circumstances where the settlement of Transocean Partners phantom awards as described above would result in adverse U.S. tax treatment to the holder, such award will become fully vested and assumed by Transocean, and the holder will receive a replacement award with respect to a number of Transocean shares equal to the number of vested Transocean Partners phantom units multiplied by the Exchange Ratio, rounded down to the nearest whole share.  Settlement of such award of Transocean shares will be made as soon as practicable after such settlement would not result in adverse U.S. tax consequences to the holder.

The Special Meeting; Common Units Entitled to Vote; Required Vote (page [  ])

The special meeting of Transocean Partners’ common unitholders will be held on [    ], 2016, at [  ]:[  ] [a.m./p.m.], local time. At the special meeting, Transocean Partners common unitholders will be asked to vote on approving the merger and the merger agreement, a copy of which is attached as Annex A to this proxy statement/prospectus.

Only Transocean Partners common unitholders of record at the close of business on September 22, 2016 will be entitled to receive notice of and to vote at the special meeting. At the close of business on the record date of September 22, 2016, there were approximately 40,914,962 Transocean Partners common units outstanding and entitled to be voted at the meeting. Each holder of Transocean Partners common units is entitled to one vote for each common unit owned as of the record date.

Approval of the merger agreement and the merger under the Transocean Partners limited liability company agreement requires the affirmative vote of a unit majority.  Under the definition of “unit majority,” as of the record date, the holders of a total of 31,084,637 outstanding common units will be required to approve the merger and the merger agreement.  As of the record date, there were 40,914,962 common units outstanding, of which 21,254,310 were owned by Transocean Holdings. Transocean Holdings has agreed to vote all of its common units “FOR” the merger and the merger agreement. Therefore, the affirmative vote of the holders of an additional 9,830,327 outstanding common units, or a majority of the outstanding common units not owned by Transocean Holdings, is required to approve the proposal to approve the merger agreement and the merger.  Transocean Partners cannot complete the merger unless its common unitholders approve the merger agreement and the merger. A Transocean Partners common unitholder’s abstention, failure to vote or the failure of a Transocean Partners common unitholder who holds his or her units in “street name” through a broker, bank or other nominee to give voting instructions to such broker, bank or other nominee will have the same effect as votes “AGAINST” approval of the merger agreement and the merger.

Pursuant to the merger agreement, Transocean and Transocean Holdings have each agreed to vote, or cause to be voted, all equity interests, including all common units, of Transocean Partners then owned beneficially or of record by it or any of its subsidiaries “FOR” the approval of the merger agreement and the merger. Transocean, Transocean Holdings and their subsidiaries beneficially own approximately 52% of the outstanding Transocean Partners common units as of the record date. The affirmative vote of holders of at least a majority of the outstanding subordinated units and the approval of Transocean Holdings, as the Transocean Member, is also required to approve the merger and the merger agreement.  Transocean Holdings owns all of the outstanding subordinated units and has voted those units to approve the merger agreement and the merger.  Transocean Holdings, as the Transocean Member, has also approved the merger agreement and the merger.

It is expected that Transocean Partners’ directors and executive officer will vote their common units “FOR” the approval of the merger agreement and the merger, although none of them has entered into any agreement requiring them to do so. On the record date, directors and the executive officer of Transocean Partners and their affiliates beneficially owned 0.03% of the outstanding Transocean Partners common units.

Recommendation of the Transocean Partners Conflicts Committee and the Transocean Partners Board and Their Reasons for the Merger (page [  ])

The Transocean Partners Conflicts Committee and the Transocean Partners Board each recommend that Transocean Partners common unitholders vote “FOR” approval of the merger agreement and the merger.

In the course of reaching its decision to approve the merger agreement and the transactions contemplated thereby, including the merger, each of the Transocean Partners Conflicts Committee and the Transocean Partners Board considered a number of factors in its deliberation. For a more complete discussion of these factors, see “The Merger—Transocean Partners Conflicts Committee and Transocean Partners Board Reasons for the Merger” and “The Merger—Recommendation of the Transocean Partners Conflicts Committee and Transocean Partners Board.”

No Transocean Shareholder Approval Required

Transocean shareholders are not required to approve the merger agreement or the merger or the issuance of Transocean shares in connection with the merger.

Opinion of Evercore Group L.L.C.—Financial Advisor to the Transocean Partners Conflicts Committee (page [ ])

At the request of the Transocean Partners Conflicts Committee at a meeting of the Transocean Partners Conflicts Committee held on July 31, 2016, Evercore Group L.L.C. (“Evercore”) rendered its oral opinion to the Transocean Partners Conflicts Committee that, as of July 31, 2016, based upon and subject to the assumptions, qualifications, limitations and other matters considered by Evercore in connection with the preparation of its opinion, the Exchange Ratio provided for pursuant to the merger agreement is fair, from a financial point of view, to Transocean Partners Public Unitholders. Evercore subsequently confirmed its oral opinion in writing dated July 31, 2016 to the Transocean Partners Conflicts Committee (the “Written Opinion”). In the sections of this proxy statement/prospectus regarding Evercore’s opinion and related analyses, references to the “Transaction” means the merger and the related transactions contemplated by the merger agreement.

Evercore’s opinion was directed to the Transocean Partners Conflicts Committee (in its capacity as such), and only addressed the fairness from a financial point of view, as of the date of the opinion, to the Transocean Partners Public Unitholders of the Exchange Ratio provided for pursuant to the merger agreement. Evercore’s opinion did not address any other term or aspect of the merger agreement or the Transaction. The full text of the Written Opinion, which describes the assumptions made, procedures followed, matters considered, and qualifications and limitations of the review undertaken by Evercore in rendering its opinion, is attached as Annex B to this proxy statement/prospectus. The summary of Evercore’s opinion set forth in this proxy statement/prospectus is qualified in its entirety by reference to the full text of the Written Opinion. However, neither the Written Opinion nor the summary of such opinion and the related analyses set forth in this proxy statement/prospectus are intended to be, and they do not constitute, a recommendation as to how unitholders of Transocean Partners or any other person should act or vote with respect to any matter relating to the Transaction or any other matter.

Ownership of Transocean After the Merger

Based on the number of Transocean Partners common units and Transocean Partners phantom units outstanding as of September 20, 2016, Transocean expects to issue approximately 22.7 million Transocean shares to former Transocean Partners common unitholders pursuant to the merger. Based on the number of Transocean shares outstanding as of the date of this proxy statement/prospectus, immediately following the completion of the merger, Transocean expects to have approximately 388.1 million Transocean shares outstanding.  Former Transocean Partners public common unitholders are therefore expected to hold approximately 5.8% of the aggregate number of Transocean shares outstanding immediately after the merger.

Interests of Directors and the Executive Officer of Transocean Partners in the Merger (page [  ])

Transocean Partners’ directors and executive officer have interests in the merger that are different from, or in addition to, the interests of Transocean Partners common unitholders generally. The members of the Transocean Partners Board and Transocean Partners Conflicts Committee were aware of and considered these interests, among other matters, in evaluating and negotiating the merger agreement and the merger, and in recommending to Transocean Partners common unitholders that the merger and the merger agreement be approved.

These interests include:

Please see “The Merger—Interests of Directors and the Executive Officer of Transocean Partners in the Merger” for more information.

Listing of Transocean Shares; Delisting and Deregistration of Transocean Partners Common Units (page [  ])

Transocean shares are currently listed on the NYSE under the ticker symbol “RIG.” Transocean will apply to list the Transocean shares to be issued in the merger on the NYSE, subject to official notice of issuance.

Transocean Partners common units are currently listed on the NYSE under the ticker symbol “RIGP.” If the merger is completed, Transocean Partners common units will cease to be listed on the NYSE and will be deregistered under the Exchange Act.

No Appraisal Rights

Appraisal rights are not available in connection with the merger under Marshall Islands law or under the Transocean Partners limited liability company agreement.

Conditions to Completion of the Merger (page [  ])

The respective obligations of each party to effect the merger is subject to the satisfaction or, to the extent permitted by law, waiver of certain conditions, including, but not limited to, the following:

In addition, Transocean Partners’ obligation to effect the merger is subject to, among other things, the receipt by Transocean of an opinion of Baker Botts L.L.P., counsel to Transocean, or another nationally recognized law firm experienced in such matters, to the effect that for U.S. federal income tax purposes, the merger will be treated as a reorganization under Section 368(a) of the Internal Revenue Code of 1986, as amended.

No Solicitation by Transocean Partners (page [  ])

Under the merger agreement, Transocean Partners has agreed not to (or authorize any of its directors, officers, members, employees, representatives, agents, attorneys, consultants, contractors, accountants, financial advisors and other advisors to), among other things:

However, before the approval of the merger and of the merger agreement by the Transocean Partners common unitholders, Transocean Partners may, under certain circumstances, engage in negotiations with and provide information regarding Transocean Partners to a third party making an unsolicited, written acquisition proposal that the Transocean Partners Board or the Transocean Partners Conflicts Committee concludes in good faith is reasonably likely to be superior to the merger and the failure to take the action would be inconsistent with the directors’ duties under the Transocean Partners limited liability company agreement or applicable Marshall Islands law.

Termination of the Merger Agreement (page [  ])

Either the Transocean Partners Board (upon the recommendation of the Transocean Partners Conflicts Committee) or Transocean may terminate the merger agreement and abandon the merger at any time prior to the effective time of the merger if:

The Transocean Partners Board (upon the recommendation of the Transocean Partners Conflicts Committee) may terminate the merger agreement and abandon the merger at any time, after consultation with its outside legal counsel, if:

Transocean may terminate the merger agreement at any time, after consultation with its outside legal counsel, if:

Termination Fees and Expenses (page [  ])

Transocean Partners will be required to pay to Transocean a termination fee of $15 million if the merger agreement is terminated:

If the merger agreement is terminated by Transocean or Transocean Partners because of a failure to obtain approval of the merger agreement by the Transocean Partners common unitholders, other than in any circumstances where a termination fee is payable as described above, then Transocean Partners would be required to reimburse Transocean for its costs and expenses (including all fees and expenses of counsel, accountants, consultants, financial advisors, financing sources and investment bankers of such party and its affiliates) in connection with the authorization, preparation, negotiation, execution, financing and performance of the merger agreement and all other matters related to the merger, up to a maximum of $2.5 million. 

If Transocean Partners has already reimbursed Transocean for its costs and expenses and a termination fee later becomes payable by Transocean Partners, the amount of such costs and expenses so reimbursed will be offset against the $15 million termination fee payable.

Payment of Cash Distributions (page [  ])

Transocean

Transocean has not paid any cash distributions on Transocean shares since September 2015.

Transocean Partners

Transocean Partners common unitholders will receive distributions on their Transocean Partners common units for the quarter ending June 30, 2016 and will receive distributions for any future quarter for which the record date with respect to a distribution approved by the Transocean Partners Board in accordance with the terms of the merger agreement occurs prior to the effective time of the merger. Under the terms of the merger agreement, Transocean Partners may make quarterly cash distributions not to exceed $0.3625 per unit with declaration, record and payment dates reasonably consistent with past practice; provided that the parties have agreed to coordinate the timing of the closing of the merger to facilitate the payment of the regular quarterly cash distribution on the Transocean Partners common units for the quarter ending September 30, 2016, the record date for which will be prior to the closing of the merger.

Comparison of Rights of Shareholders and Common Unitholders (page [  ])

Transocean Partners common unitholders will own Transocean shares following the completion of the merger, and their rights associated with those Transocean shares will be governed by the Transocean articles of association and Swiss law, which differ in a number of respects from the Transocean Partners limited liability company agreement and Marshall Islands law.

Material U.S. Federal Income Tax Consequences of the Merger (page [  ])

Except in certain circumstances described in “The Merger—Material U.S. Federal Income Tax Consequences,” a  U.S. Holder (as defined below) generally will not recognize any gain or loss for U.S. federal income tax purposes upon the exchange of Transocean Partners common units for Transocean shares in the merger.  A Non-U.S. Holder (as defined below) generally will not recognize any gain or loss for U.S. federal income tax purposes upon the exchange of Transocean Partners common units for Transocean shares in the merger.

Please refer to “The Merger—Material U.S. Federal Income Tax Consequences” beginning on page [  ] of this proxy statement/prospectus for a description of the material U.S. federal income tax consequences of the merger.  Determining the actual tax consequences of the merger to you may be complex and will depend on your specific situation.  You should consult your tax advisor for a full understanding of the tax consequences of the merger to you.

Marshall Islands Tax Consequences of the Merger (page [  ])

Please refer to “The Merger—Marshall Islands Tax Consequences of the Merger” beginning on page [  ] of this proxy statement/prospectus for a description of Marshall Islands tax consequences of the merger.

U.K. Tax Consequences of the Merger (page [  ])

Please refer to “The Merger—U.K. Tax Consequences of the Merger” beginning on page [  ] of this proxy statement/prospectus for a description of United Kingdom (“U.K.”) tax consequences of the merger.

Accounting Treatment of the Merger (page [  ])

Transocean will account for the merger in accordance with accounting standards generally accepted in the U.S. with regard to consolidation and changes in a parent’s ownership interest in a subsidiary.  Because Transocean retains a controlling financial interest in Transocean Partners before and after the transaction, the transaction will be accounted for as an equity transaction.  Therefore, no gain or loss shall be recognized in consolidated net income or total comprehensive income.

Regulatory Approvals Required for the Merger (page [  ])

Transocean and Transocean Partners are not required to make notifications under the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended, and the rules promulgated thereunder by the Federal Trade Commission.

Risk Factors Relating to the Merger and Ownership of Transocean Shares (page [  ])

Transocean Partners common unitholders should consider carefully all the risk factors together with all of the other information included or incorporated by reference in this proxy statement/prospectus before deciding how to vote. Risks relating to the merger and ownership of Transocean shares are described in the section titled “Risk Factors.” Some of these risks include, but are not limited to, those described below:

Selected Historical Consolidated Financial Data of Transocean

The selected financial data of Transocean as of December 31, 2015 and 2014 and for each of the three years in the period ended December 31, 2015 have been derived from the audited consolidated financial statements included in “Item 8. Financial Statements and Supplementary Data” of Transocean’s annual report on Form 10‑K for the year ended December 31, 2015.  The selected financial data as of June 30, 2016 and for each of the six-month periods ended June 30, 2016 and 2015 have been derived from the unaudited condensed consolidated financial statements included in “Item 1. Financial Statements” of Transocean’s quarterly report on Form 10‑Q for the quarterly period ended June 30, 2016.  The selected financial data as of December 31, 2013, 2012 and 2011 and for each of the two years in the period ended December 31, 2012 have been derived from Transocean’s accounting records.

The selected financial data should be read in conjunction with the sections entitled “Management’s Discussion and Analysis of Financial Condition and Results of Operations” and the consolidated financial statements and notes thereto in Transocean’s annual report on Form 10-K for the year ended December 31, 2015, and in Transocean’s quarterly report on Form 10-Q for the quarterly period ended June 30, 2016, and Transocean’s financial statements, related notes and other financial information incorporated by reference in this proxy statement/prospectus. See “Where You Can Find More Information.”

Selected Historical Consolidated Financial Data of Transocean Partners

The selected financial data of Transocean Partners as of December 31, 2015 and 2014 and for each of the three years in the period ended December 31, 2015 have been derived from the audited consolidated financial statements included in “Item 8. Financial Statements and Supplementary Data” of Transocean Partners’ annual report on Form 10‑K for the year ended December 31, 2015.  The selected financial data as of June 30, 2016 and for each of the six-month periods ended June 30, 2016 and 2015 have been derived from the unaudited condensed consolidated financial statements included in “Item 1. Financial Statements” of Transocean Partners’ quarterly report on Form 10‑Q for the quarterly period ended June 30, 2016.  The selected financial data as of December 31, 2013 and 2012 and for the year ended December 31, 2012 have been derived from Transocean Partners’ accounting records.

For periods prior to August 5, 2014, the combined financial information of the Transocean Partners LLC predecessor was derived from Transocean’s accounting records. The combined financial information reflects the combined results of operations, financial position and cash flows of the Transocean Partners LLC predecessor business as if such operations and assets had been combined for all periods presented. For the periods following August 5, 2014, the consolidated financial statements reflect Transocean Partners’ consolidated results of operations, financial position and cash flows.

As a company with less than $1 billion in revenues during its last fiscal year, Transocean Partners qualifies as an emerging growth company as defined in the Jumpstart Our Business Startups Act of 2012. As an emerging growth company, Transocean Partners may, for up to five years after the date of its initial public offering, take advantage of specified exemptions from reporting and other regulatory requirements that are otherwise applicable generally to public companies. Among other exemptions, these include the presentation of only two years of audited financial statements and only two years of related Management’s Discussion and Analysis of Financial Condition and Results of Operations in the registration statement of an initial public offering of common equity securities and the reporting of incremental years in the succeeding years for purposes of providing selected financial data.

The selected financial data should be read in conjunction with the sections entitled “Management’s Discussion and Analysis of Financial Condition and Results of Operations” and the consolidated financial statements and notes thereto in Transocean Partners’ annual report on Form 10-K for the year ended December 31, 2015, and in Transocean Partners’ quarterly report on Form 10-Q for the quarterly period ended June 30, 2016, and Transocean Partners’ financial statements, related notes and other financial information incorporated by reference in this proxy statement/prospectus. See “Where You Can Find More Information.”

Unaudited Comparative Per Share and Per Unit Data

The following table presents the following: (1) historical per share information of Transocean, (2) unaudited pro forma per share information of Transocean after giving pro forma effect to the merger, including the issuance of 1.1427 Transocean shares for each outstanding Transocean Partners common unit not owned by Transocean or its subsidiaries and (3) the historical and equivalent pro forma per share information of Transocean Partners.

The combined company unaudited pro forma per share information was derived from the historical consolidated financial statements of Transocean and Transocean Partners. You should read this information together with the historical consolidated financial statements and related notes of Transocean and Transocean Partners that are filed with the SEC and incorporated by reference into this proxy statement/prospectus. See “Where You Can Find More Information.”

The unaudited pro forma data is for informational purposes only. The companies may have performed differently had they always been combined.  You should not rely on the pro forma data as being indicative of the historical results that would have been achieved had the companies always been combined or the future results that the combined company will experience after completion of the merger.

The calculation for the combined company unaudited pro forma distributions per share was as follows (in millions, except per share data):

The calculation for the combined company unaudited pro forma book value per share was as follows (in millions, except per share data):

Comparative Per Share and Per Unit Market Price And Dividend Information

The following table sets forth, for the periods indicated, the intra-day high and low sales prices per Transocean share and per Transocean Partners common unit as reported on the NYSE, which is the principal trading market for both Transocean shares and Transocean Partners common units, and the cash dividends and distributions declared per Transocean share and per Transocean Partners common unit.