RIG Transocean Ltd

TABLE OF CONTENTS

QUESTIONS AND ANSWERS

The following are answers to some questions that you may have regarding the proposed transaction between Transocean and Ocean Rig and the other proposals being considered at the Transocean Extraordinary General Meeting and the Ocean Rig Extraordinary General Meeting.  Transocean and Ocean Rig urge you to read carefully this entire joint proxy statement/prospectus, including the Appendices, and the documents incorporated by reference into this joint proxy statement/prospectus, because the information in this section does not provide all the information that might be important to you.  See “Where You Can Find More Information.”

All references in this joint proxy statement/prospectus to:

All references in this joint proxy statement/prospectus to “we,” “us,” and “our” refer to Transocean and Ocean Rig, collectively, unless the context otherwise requires. All references in this joint proxy statement/prospectus to “$” are to United States dollars, and all references to “CHF” are to Swiss francs.

Q: What is the proposed transaction?

A: Transocean and Ocean Rig are proposing a business combination transaction pursuant to which, among other things, Merger Sub will merge with and into Ocean Rig, with Ocean Rig continuing as the surviving entity and a wholly-owned, indirect subsidiary of Transocean. A copy of the Merger Agreement is attached as Appendix A to this joint proxy statement/prospectus. At the effective time of the Merger (the “ Effective Time ”), Transocean will be the indirect holder of all of the assets of Ocean Rig.

Q: What will happen in the proposed transaction?

A: Transocean, Ocean Rig, Holdco and Merger Sub have entered into the Merger Agreement pursuant to which, among other things, Merger Sub will merge with and into Ocean Rig, with Ocean Rig continuing its corporate existence as the surviving entity in the Merger and as a wholly-owned indirect subsidiary of Transocean. At the Effective Time, each issued and outstanding Ocean Rig share will be cancelled and automatically converted into the right to receive 1.6128 Transocean shares (the “ Share Consideration ”) and $12.75 in cash (the “ Cash Consideration ” and, together with the Share Consideration, the “ Merger Consideration ”). Any resulting fractional Transocean shares will be rounded down to the nearest whole number of Transocean shares and paid in cash .

Q: Why am I receiving this joint proxy statement/prospectus?

A: Each of Transocean and Ocean Rig will hold separate extraordinary general meetings of their respective shareholders to obtain the required shareholder approvals and to consider other proposals as described elsewhere in this joint proxy statement/prospectus. The Transocean board of directors (the “ Transocean Board ”) and the Ocean Rig board of directors (“ Ocean Rig Board ”) are using this joint proxy statement/prospectus to solicit proxies from the shareholders of Transocean and Ocean Rig, respectively, in connection with the respective extraordinary general meetings being held in connection with the Merger and the other related transactions.

In addition, Transocean is using this joint proxy statement/prospectus as a prospectus for Ocean Rig shareholders because Transocean shares will be issued as the Share Consideration in the Merger.

This joint proxy statement/prospectus contains important information about the Merger Agreement, the Merger and the other transactions contemplated by the Merger Agreement as well as information about the proposals begin voted on at the extraordinary general meeting and you should read it carefully. The enclosed voting materials allow you to vote your Transocean shares or Ocean Rig shares, as applicable, without attending the extraordinary general meetings .

Q: What are Transocean shareholders being asked to vote on and why is this approval necessary?

A: Transocean shareholders are being asked to approve an amendment to Transocean’s Articles of Association to create additional authorized share capital, pursuant to which the Transocean Board is authorized to issue, subject to and upon completion of the Merger, and on a non-preemptive rights basis, up to 147,700,195 new Transocean shares to pay the Share Consideration in the Merger (the “ Authorized Share Capital Proposal ”). In addition, Transocean shareholders are being asked to approve the issuance of up to 147,700,195 new Transocean shares to pay the Share Consideration in the Merger, as required by the rules of the New York Stock Exchange (the “ Share Issuance Proposal ”). The approval of each of these proposals is a condition to completion of the Merger.

In addition, Transocean shareholders are being asked to vote on a proposal to amend Transocean’s Articles of Association to delete the special purpose authorized share capital included in Article 5 bis of Transocean’s Articles of Association (the “ Clean-Up Proposal ”). The approval of this proposal is not a condition to the Merger.

Q: How does the Transocean Board recommend that Transocean shareholders vote on the proposals?

A: The Transocean Board recommends that Transocean shareholders vote “ FOR ” all proposals.

Q: What are Ocean Rig shareholders being asked to vote on and why is this approval necessary?

A: The Merger cannot be completed unless the Ocean Rig shareholders vote to approve the Merger Agreement and the other transactions contemplated by the Merger Agreement (the “ Merger Agreement Proposal ”). This approval is a condition to completion of the Merger.

In addition, Ocean Rig shareholders are being asked to vote on a proposal to adjourn the Ocean Rig Extraordinary General Meeting if necessary or advisable, to solicit additional proxies in favor of the Merger or to take any other action in connection with the Merger Agreement (the “ Adjournment Proposal ”). Approval of this proposal is not a condition to the Merger.

Q: How does the Ocean Rig Board recommend that Ocean Rig shareholders vote on the proposals?

A: The Ocean Rig Board unanimously recommends that Ocean Rig shareholders vote “ FOR ” all proposals.

Q: How will Transocean shareholders be affected by the Merger and the issuance of shares to Ocean Rig shareholders in the Merger?

A: After the Merger, each Transocean shareholder will continue to own the same number of Transocean shares that the shareholder held immediately prior to the Merger. However, because Transocean will be issuing new shares to Ocean Rig shareholders in the Merger, each outstanding Transocean share immediately prior to the Merger will represent a smaller percentage of the aggregate number of shares of Transocean outstanding after the Merger. Upon the completion of the Merger, based on the number of Transocean shares and Ocean Rig shares outstanding as of September  ,  2018, the latest practicable trading day before the date of this joint proxy statement/prospectus, we estimate that continuing Transocean shareholders will own approximately 76%  of the issued and outstanding Transocean shares, and former Ocean Rig shareholders will own approximately 24%  of the issued and outstanding Transocean shares.

Q: What happens if the market prices of Transocean shares or Ocean Rig shares change before the closing of the Merger?

A: No change will be made to the Merger Consideration as a result of changes in the market price of Transocean shares or Ocean Rig shares before the Merger. The Merger Consideration was fixed in the Merger Agreement and will not be adjusted for changes in the market prices of either Transocean shares or Ocean Rig shares. Because of this, the implied value of the Merger Consideration will fluctuate between now and the completion of the Merger.

Q: Why are Transocean and Ocean Rig proposing the Merger?

A: The Transocean Board and the Transaction Committee of the Transocean Board (the “ Transaction Committee ”), in consultation with Transocean’s legal and financial advisors and Transocean’s management, considered various factors before unanimously determining that a strategic business combination with Ocean Rig was advisable and in the best interests of Transocean. The Ocean Rig Board, after consultation with Ocean Rig’s legal and financial advisors and consideration of a number of factors, unanimously determined that the Merger is in the best interests of Ocean Rig and its shareholders. See the sections titled “The Merger—Transocean’s Reasons for the Merger” and “The Merger—Recommendation of the Ocean Rig Board and Its Reasons for the Merger” for more information.

Q: Will there be any changes to the board of directors and management of Transocean or Ocean Rig after the Merger?

A: Transocean .  There will be no changes to the Transocean Board or to the management of Transocean as a result of the Merger.

Ocean Rig .  At the Effective Time, the members of the Ocean Rig Board will resign and management will cease to perform any services for either Ocean Rig or Transocean. TMS Offshore Ltd. (“ TMS ”), a company which provides certain management services to Ocean Rig and its subsidiaries pursuant to management services agreements (the “ Management Services Agreements ”) and which may be deemed to be beneficially owned by Ocean Rig’s Chairman, George Economou, has agreed in principle to use commercially reasonable efforts to negotiate and execute a transition services agreement with Ocean Rig at the closing of the Merger. The transition

services agreement will provide for certain services currently provided by TMS to Ocean Rig under the Management Services Agreements for an interim period after the closing of the Merger on terms reasonably consistent with industry standards.

Q: When and where are the extraordinary general meetings ?

A: Transocean .  The Transocean Extraordinary General Meeting will be held at Transocean’s offices in Steinhausen, Switzerland, on [  ], 2018 commencing at [  ], Swiss time.

Ocean Rig .  The Ocean Rig Extraordinary General Meeting will be held at [  ], on [  ], 2018 commencing at [  ] p.m. (EST).

Q: Who can vote at the extraordinary general meetings ?

A: Transocean .  All Transocean shareholders of record as of the close of business on [  ], 2018, the record date for determining shareholders entitled to notice of and to vote at the Transocean Extraordinary General Meeting, are entitled to receive notice of and to vote at the Transocean Extraordinary General Meeting.  As of the date of this joint proxy statement/prospectus, there were [  ]  Transocean shares outstanding and entitled to vote at the Transocean Extraordinary General Meeting, held by approximately [  ] holders of record. Each Transocean share is entitled to one vote on each proposal presented at the Transocean Extraordinary General Meeting.

Ocean Rig .  All Ocean Rig shareholders of record as of the close of business on [  ], 2018, the record date for determining shareholders entitled to notice of and to vote at the Ocean Rig Extraordinary General Meeting, are entitled to receive notice of and to vote at the Ocean Rig Extraordinary General Meeting. As of the record date, there were [  ]  Ocean Rig shares outstanding and entitled to vote at the Ocean Rig Extraordinary General Meeting, held by approximately [  ] holders of record. Each Ocean Rig share is entitled to one vote on each proposal presented at the Ocean Rig Extraordinary General Meeting.

Q: What constitutes a quorum?

A: Transocean .  Transocean’s Articles of Association provide that the presence of shareholders, in person or by proxy, holding at least a majority of all the shares entitled to vote at the meeting constitutes a quorum for purposes of convening the Transocean Extraordinary General Meeting and voting on all of the matters described in the notice of meeting.

Ocean Rig .  Ocean Rig's Articles of Association provide that there must be present either in person or by proxy shareholders of record holding at least one-third of the shares issued and outstanding and entitled to vote at the Ocean Rig Extraordinary General Meeting in order to constitute a quorum.

Q: What vote by the Transocean shareholders is required to approve the proposals to be considered at the Transocean Extraordinary General Meeting?

A: The affirmative vote of at least two-thirds of the votes present or represented at the Transocean Extraordinary General Meeting and entitled to vote, is required to approve the Authorized Share Capital Proposal. The affirmative votes of a majority of the votes cast in person or by proxy at the Transocean Extraordinary General Meeting is required to approve the Share Issuance Proposal and the Clean-Up Proposal.

Q: What vote by the Ocean Rig shareholders is required to approve the proposals to be considered at the Ocean Rig Extraordinary General Meeting?

A: The affirmative vote of holders of Ocean Rig shares representing two-thirds of the Ocean Rig shares present and voting in person or by proxy as a single class at the Ocean Rig Extraordinary General Meeting is required to approve the Merger Agreement Proposal.

The affirmative vote of holders of Ocean Rig shares representing a majority of the Ocean Rig shares present and voting in person or by proxy as a single class at the Ocean Rig Extraordinary General Meeting is required to approve the Adjournment Proposal.

Q: Are there any conditions to closing of the Merger that must be satisfied for the Merger to be completed?

A: Closing of the Merger is contingent upon, among other things, the approval (1) by Transocean’s shareholders of the Authorized Share Capital Proposal and the Share Issuance Proposal, and (2) by Ocean Rig shareholders of the Merger Agreement.

Additional conditions to the Merger include: (1) that no applicable law prohibits the consummation of the Merger; (2) that all applicable waiting periods related to the antitrust laws of Brazil and Norway have expired or been terminated, and all pre-closing approvals reasonably required have been obtained; (3) that the authorized share capital approved by shareholders at the Transocean Extraordinary General Meeting under the Authorized Share Capital Proposal, the issuance of Transocean shares as Share Consideration in the Merger and the related amendments to Transocean’s Articles of Association have each been registered with the commercial register in the Canton of Zug, Switzerland; (4) that the Form S-4 has been declared effective, no stop order suspending the effectiveness of the Form S-4 is in effect and no proceedings for such purpose are pending before or threatened by the SEC; and (5) that the Transocean shares being issued as Share Consideration in the Merger have been approved for listing on the NYSE, subject to official notice of issuance.

Additionally, the obligations of Transocean and its subsidiaries party to the Merger Agreement to effect the Merger and to consummate the other transactions contemplated by the Merger Agreement are subject to the satisfaction at or prior to the Effective Time of each of the following conditions: (1) the accuracy of the representations and warranties made by Ocean Rig in the Merger Agreement, subject to certain materiality thresholds; (2) performance (or cure of any non-performance) in all material respects by Ocean Rig of the covenants and agreements required to be performed by it prior to completion of the Merger; (3) since the date of the Merger Agreement, there has not occurred a willful breach of Ocean Rig’s covenants and agreements to provide assistance in connection with the Financing; (4) since the date of the Merger Agreement, no circumstances have occurred that have had or would reasonably be expected to have a Material Adverse Effect (as defined in the Merger Agreement) on Ocean Rig; (5) certain Ocean Rig management services agreements having been terminated; and (6) Ocean Rig will have delivered to Transocean a certificate certifying that certain of the closing conditions have been satisfied.

The obligations of Ocean Rig to effect the Merger and to consummate the other transactions contemplated by the Merger Agreement are subject to the satisfaction at or prior to the Effective Time of each of the following conditions: (1) the accuracy of the representations and warranties made by Transocean in the Merger Agreement, subject to certain materiality thresholds; (2) performance (or cure of any non-performance) in all material respects by Transocean of the covenants and agreements required to be performed by it prior to completion of the Merger; (3) since the date of the Merger Agreement, no circumstances have occurred that have had or would reasonably be expected to have a Material Adverse Effect (as defined in the Merger Agreement) on Transocean; and (4) Transocean will have delivered to Ocean Rig a certificate certifying that certain of the closing conditions have been satisfied.

See “The Merger Agreement—Conditions to Completion of the Merger” for further information about the conditions that must be satisfied to complete the Merger.

Q: Are there risks associated with the Merger that I should consider in deciding how to vote?

A: Yes. There are a number of risks related to the Merger that are discussed in this joint proxy statement/prospectus described in the section entitled “Risk Factors.”

Q: If my Transocean shares or my Ocean Rig shares are held in “street name” by my broker, bank or other nominee, will my broker, bank or other nominee vote my Transocean shares or my Ocean Rig shares for me?

A: Transocean .  If you hold your shares in the name of a bank, broker or other nominee, you should follow the instructions provided by your bank, broker or nominee for voting your shares. Many Transocean shareholders hold their shares in more than one account and may receive more than one proxy card or voting instruction form. To ensure that all of your shares are represented at the Transocean Extraordinary General Meeting, please submit voting instructions for each account.

Under NYSE rules, brokers who hold shares in “street name” for customers, such that the shares are registered on the books of Transocean as being held by the brokers, have the authority to vote on “routine” proposals when they have not received instructions from beneficial owners, but are precluded from exercising their voting discretion with respect to proposals for “non-routine” matters. The Authorized Share Capital Proposal and the Share Issuance Proposal being considered at the Transocean Extraordinary General Meeting are “non-routine” matters under NYSE rules, but the Clean-Up Proposal is a “routine” matter under NYSE rules. If you hold your shares in “street name,” your broker will not be able to vote your shares on the Authorized Share Capital Proposal and the Share Issuance Proposal unless your broker receives appropriate instructions from you. We recommend that you contact your broker to exercise your right to vote your shares.

Ocean Rig .  If you hold your shares in the name of a bank, broker or other nominee, you should follow the instructions provided by your bank, broker or nominee for voting your shares. Many Ocean Rig shareholders hold their shares in more than one account and may receive more than one proxy card or voting instruction form. To ensure that all of your shares are represented at the Ocean Rig Extraordinary General Meeting, please submit voting instructions for each account.

If you hold your shares in “street name,” only your broker will be able to vote your shares on the Merger Agreement Proposal. Please follow the voting instructions provided by your broker, bank, trust or other nominee. Please note that you may not vote shares held in street name by returning a proxy card or voting instruction directly to Ocean Rig or by voting in person at the Ocean Rig Extraordinary General Meeting or special meetings unless you provide a “legal proxy,” which you must obtain from your broker, bank, trust or other nominee. We recommend that you contact your broker to exercise your right to vote your shares.

Q: What happens if I do not vote for a proposal?

A: Transocean .  Because the affirmative vote of at least two-thirds of the votes, each as present or represented at the Transocean Extraordinary General Meeting and entitled to vote, is required to approve the Authorized Share Capital Proposal, an abstention or invalid vote cast at the Transocean Extraordinary General Meeting will have the effect of a vote “against” this proposal. The affirmative votes of a majority of the votes cast in person or by proxy at the Transocean Extraordinary General Meeting is required to approve the Share Issuance Proposal and the Clean-Up Proposal, therefore abstentions or invalid votes do not have any effect on the outcome of those proposals. Broker non-votes do not have any effect on the outcome of the vote on any of the proposals.

Ocean Rig .  If you abstain from voting, fail to cast your vote in person, fail to complete and return your proxy card in accordance with the instructions set forth on the proxy card, or fail to give voting instructions to your broker, bank or other nominee, your vote will not be counted at the Ocean Rig Extraordinary General Meeting. Abstentions and broker non-votes are counted as present and entitled to vote at the Ocean Rig Extraordinary General Meeting for purposes of determining a quorum.  A broker non-vote occurs when a nominee holding shares for a beneficial owner does not vote on a particular proposal because the nominee does not have discretionary voting power for that particular item and has not received instructions from the beneficial owner.

Q: Will my rights as a shareholder change as a result of the Merger?

A: The rights of Transocean shareholders will be substantially unchanged as a result of the Merger. Ocean Rig shareholders will have different rights following completion of the Merger due to the differences between the governing documents of Transocean and Ocean Rig. For more information regarding the differences in shareholder rights, see “Comparison of Rights of Shareholders of Transocean and Shareholders of Ocean Rig.”

Q: When is the Merger expected to be completed?

A: Transocean and Ocean Rig expect to complete the Merger as soon as reasonably practicable following satisfaction of all of the required conditions.  If all conditions to closing the Merger are satisfied or waived, we expect that the Merger will be completed in first quarter of 2019. However, there is no guarantee that the conditions to the Merger will be satisfied by this time or at all or that the Merger will close.

The Merger Agreement contains an end date of March 31, 2019 for the completion of the Merger (which, subject to certain conditions, may be extended until September 3, 2019 as set forth in the Merger Agreement). For a discussion of the conditions to the completion of the Merger, see the section “The Merger Agreement—Conditions to Completion of the Merger Agreement.”

Q: Do I need to do anything with my share certificates or book-entry shares now?

A: No. If you are an Ocean Rig shareholder, you should not submit or attempt to exchange your share certificates or book-entry shares at this time. After the Merger is complete, if you held Ocean Rig shares, the exchange agent for the Merger will send you a letter of transmittal and instructions for exchanging your Ocean Rig shares for the Merger Consideration pursuant to the terms of the Merger Agreement. Upon surrender of a certificate or book-entry share for cancellation along with the executed letter of transmittal and other required documents described in the instructions, an Ocean Rig shareholder will receive the Merger Consideration pursuant to the terms of the Merger Agreement. The value of any fractional shares to which a holder would otherwise be entitled will be paid in cash.

Q: What are the anticipated tax consequences to me of the Merger?

A: Certain U.S. Federal Income Tax Considerations. A U.S. Holder (as defined in “Material U.S. Federal Income Tax Consequences”) of Ocean Rig shares that exchanges Ocean Rig shares for Transocean shares and cash in the Merger will generally recognize taxable gain or loss for U.S. federal income tax purposes equal to the difference between (i) the sum of the cash plus the fair market value of Transocean shares received (determined as of the date the shares are issued pursuant to the Merger) and (ii) the U.S. holder’s adjusted tax basis in the Ocean Rig shares surrendered in the Merger in exchange for Transocean shares and cash.

A Non-U.S. Holder (as defined in “Material U.S. Federal Income Tax Consequences”) will generally not be subject to U.S. federal income tax on any gain recognized on the exchange of Ocean Rig shares for Transocean shares and cash pursuant to the Merger unless (i) the gain is “effectively connected” with the Non-U.S. Holder’s conduct of a trade or business in the United States (and, if required by an applicable income tax treaty, attributable to a permanent establishment maintained by the Non-U.S. Holder in the United States) or (ii) the Non-U.S. Holder is an individual present in the United States for 183 or more days in the taxable year of the exchange, and certain other requirements are met.

The foregoing is a brief summary of U.S. federal income tax consequences only and is qualified by the description of U.S. federal income tax considerations in “Material U.S. Federal Income Tax Consequences.”  Tax matters are very complicated, and the tax consequences of the Merger to a particular holder will depend in part on such holder’s circumstances. Accordingly, holders of Ocean Rig shares are urged to consult their own tax advisors for a full understanding of the tax consequences of the Merger to them, including the applicability of U.S. federal, state, local and foreign income and other tax laws.

Certain Swiss Tax Considerations. Swiss resident individuals who hold their Ocean Rig shares as private assets should not be subject to any Swiss federal, cantonal or communal income tax in connection with the Merger, if the Merger is classified as a tax-neutral quasi-merger ( Quasifusion ). The exchange of Ocean Rig shares for Transocean shares for Domestic Commercial Shareholders (as defined in “ Material Swiss Tax Consequences ”), and who, in each case, hold their Ocean Rig shares as part of a trade or business carried on in Switzerland should not be subject to any Swiss federal, cantonal or communal income tax provided the Transocean shares will carry over the (tax) book value of the Ocean Rig shares in the books of such Domestic Commercial Shareholder since the Merger should classify as a tax neutral quasi-merger ( Quasifusion ) for Swiss tax purposes. Domestic Commercial Shareholders are on the other hand required to recognize a gain or loss realized on the cash component of the Merger Consideration in their income statement for the respective taxation period and are subject to Swiss federal, cantonal and communal individual or corporate income tax, as the case may be, on any net taxable earnings (including the gain or loss realized on the cash component of the Merger Consideration) for such taxation period. Non-Swiss Shareholders (as defined in “ Material Swiss Tax Consequences ”) will not be subject to any Swiss federal, cantonal or communal income tax in connection with the Merger.

Certain Cayman Islands Tax Considerations.  At present, there are no income or profits taxes, withholding taxes, levies, registration taxes, or other duties or similar taxes or charges imposed on Cayman Islands corporations or their shareholders. The Cayman Islands currently have no form of corporate or capital gains tax and no estate duty, inheritance tax or gift tax.  Therefore, there will be no Cayman Islands tax consequences to Transocean and Ocean Rig shareholders with respect to the Merger.  This is a general summary of present law, which is subject to prospective and retroactive change. It is not intended as tax advice, does not consider any shareholder’s particular circumstances, and does not consider tax consequences other than those arising under Cayman Islands law.

Q: Are Transocean or Ocean Rig shareholders entitled to appraisal or dissenters’ rights?

A: Transocean .  Transocean shareholders are not entitled to appraisal or dissenters’ rights.

Ocean Rig .  Ocean Rig shareholders who dissent from the Merger will have the right to receive payment of the fair value of their Ocean Rig shares if the Merger is completed, but only if they deliver to Ocean Rig, before the vote on the Merger is taken at the Ocean Rig Extraordinary General Meeting , a written objection to the Merger and they subsequently comply with all procedures and requirements of Section 238 of the Cayman Islands Companies Law (2018 Revision) (the “ Cayman Companies Law ”) for the exercise of dissenter rights, an extract of which is attached as Appendix G to the joint proxy statement/prospectus. The fair value of their Ocean Rig shares as determined under that statute could be more than, the same as, or less than the Merger Consideration they would receive pursuant to the Merger Agreement if they did not exercise dissenter rights with respect to their shares.

Ocean Rig’s Memorandum and Articles of Association contain certain Drag-Along Provisions (as defined herein) that, if invoked in connection with the Merger, would require all Ocean Rig shareholders to take actions necessary to waive all dissenter’s rights, appraisal rights and similar rights in connection with the Merger. See “Risk Factors—Risks Relating to the Merger— Ocean Rig’s Memorandum and Articles of Association contain certain drag-along provisions that, if invoked, would require all Ocean Rig shareholders to support the Merger and may deter Ocean Rig from receiving proposals for alternative transactions.” At this time, neither Transocean nor Ocean Rig intends to seek to cause the Merger to be subject to these Drag-Along Provisions.

Q: What happens if the Merger is not completed?

A: If the Merger and the other transactions contemplated by the Merger Agreement are not approved by the Transocean shareholders and the Ocean Rig shareholders, or if the Merger is not completed for any other reason, Ocean Rig shareholders will not receive any form of consideration in connection with the Merger. Instead, Ocean Rig will remain an independent public company, and the Ocean Rig Class A shares will continue to be listed on Nasdaq. See “Risk Factors—Risks Relating to the Merger.”

In addition, if the Merger Agreement is terminated under specified circumstances, Ocean Rig may be required to pay Transocean a termination fee of $90 million, and under certain other specified circumstances, Transocean may be required to pay Ocean Rig $60 million, representing a reasonable estimate of Ocean Rig’s Expenses (as defined in the Merger Agreement) incurred in connection with the Merger and the transactions contemplated thereby, or a termination fee of $132.5 million. See “The Merger Agreement—Termination of the Merger Agreement—Termination Fees and Expenses.”

Q: What do I need to do now?

A: After you have carefully read this joint proxy statement/prospectus, please respond by completing, signing and dating your proxy card or voting instruction card and returning it in the enclosed preaddressed postage-paid envelope or, if available, by submitting your proxy by one of the other methods specified in your proxy card or voting instruction card as promptly as possible so that your Transocean shares or Ocean Rig shares will be represented and voted at the Transocean Extraordinary General Meeting or the Ocean Rig Extraordinary General Meeting, as applicable.

If your Transocean shares or Ocean Rig shares are held in an account at a broker, bank or other nominee, please refer to your proxy card or voting instruction card forwarded by your broker, bank or other nominee to see which voting options are available to you.

The method by which you submit a proxy will in no way limit your right to vote at the Transocean Extraordinary General Meeting or the Ocean Rig Extraordinary General Meeting, as applicable, if you later decide to attend the Transocean Extraordinary General Meeting or the Ocean Rig Extraordinary General Meeting in person.  However, if your Transocean shares or Ocean Rig shares are held in the name of a broker, bank or other nominee, you must obtain a legal proxy, executed in your favor, from your broker, bank or other nominee, to be able to vote in person at the Transocean Extraordinary General Meeting or the Ocean Rig Extraordinary General Meeting, as applicable.

Q: How will my proxy be voted if I return my proxy card without indicating how to vote?

A: Transocean .  If holders of Transocean shares have timely submitted their proxy but have not specifically indicated how to vote their Transocean shares, such Transocean shares will be voted in accordance with the recommendations of the Transocean Board with regard to the items listed in the notice of meeting.  In addition, if there are any modifications to the agenda items or proposals identified in this joint proxy statement/prospectus or other matters on which voting is permissible under Swiss law are properly presented at the Transocean Extraordinary General Meeting for consideration, you instruct the independent proxy, in the absence of other specific instructions, to vote in accordance with the recommendations of the Transocean Board.

Ocean Rig .  If holders of Ocean Rig shares have timely submitted their proxy but have not specifically indicated how to vote their Ocean Rig shares, such Ocean Rig shares will be voted in accordance with the recommendations of the Ocean Rig Board with regard to the items listed in the Ocean Rig Notice of Extraordinary General Meeting.  In addition, if there are any modifications to the agenda items or proposals identified in this joint proxy statement/prospectus or other matters on which voting is permissible under Cayman Islands law that are properly presented at the Ocean Rig Extraordinary General Meeting for consideration, the independent proxy will vote in accordance with the recommendations of the Ocean Rig Board in the absence of other specific instructions.

Q: Can I revoke my proxy or change my vote after I have delivered my proxy?

A: Transocean .  You may revoke your proxy card at any time prior to its exercise by:

-or-

-or-

Your presence without voting at the meeting will not automatically revoke your proxy, and any revocation during the meeting will not affect votes in relation to agenda items that have already been voted on. If you hold your shares in the name of a bank, broker or other nominee, you should follow the instructions provided by your bank, broker or nominee in revoking your previously granted proxy.

Ocean Rig .  Yes. If you are a holder of Ocean Rig shares, you may change your vote in one of the following three ways:

Q: What happens if I sell my shares after the record date but before the applicable extraordinary general meeting?

A: The record dates for both the Transocean Extraordinary General Meeting and the Ocean Rig Extraordinary General Meeting are earlier than both the date of the extraordinary general meetings and the date that the Merger is expected to be completed.  If you sell or otherwise transfer your Transocean shares or Ocean Rig shares after the record date for the applicable extraordinary general meeting , you will retain your right to vote at the applicable extraordinary general meeting. However, if you are an Ocean Rig shareholder and transfer your shares after the record date, you will not have the right to receive the Merger Consideration to be received by Ocean Rig’s shareholders.  In order to receive the Merger Consideration, you must own your Ocean Rig shares through the completion of the Merger.

Q: What does it mean if I receive more than one set of voting materials for the Transocean Extraordinary General Meeting or the Ocean Rig Extraordinary General Meeting?

A: You may receive more than one set of voting materials for the Transocean Extraordinary General Meeting or the Ocean Rig Extraordinary General Meeting, as applicable, including multiple copies of this joint proxy statement/prospectus and multiple proxy cards or voting instruction cards.  For example, if you hold your Transocean shares or Ocean Rig shares in more than one brokerage account, you will receive a separate voting instruction card for each brokerage account in which you hold Transocean shares or Ocean Rig shares.  If you are a holder of record and your Transocean shares or Ocean Rig shares are registered in more than one name, you

may receive more than one proxy card.  Please complete, sign, date and return each proxy card and voting instruction card that you receive or, if available, please submit your proxy by telephone or over the Internet.

Q: What happens if I am a shareholder of both Transocean and Ocean Rig?

A: You will receive separate proxy cards for each entity and must complete, sign and date each proxy card and return each proxy card in the appropriate pre-addressed postage-paid envelope or, if available, by submitting a proxy by one of the other methods specified in your proxy card or voting instruction card for each entity.

Q: What happens if the Transocean Extraordinary General Meeting is postponed or adjourned?

A: If the Transocean Extraordinary General Meeting is postponed or adjourned, your proxy will no longer be in effect and will be not voted.

Q: What happens if the Ocean Rig Extraordinary General Meeting is postponed or adjourned?

A: If the Ocean Rig Extraordinary General Meeting is postponed or adjourned, your proxy will still be in effect and will be voted at such postponed or adjourned meeting. You will be able to change or revoke your proxy until the commencement of the rescheduled meeting.

Q: Who can answer any additional questions I have?

A: If you have any questions about the Merger or the other matters to be voted on at the extraordinary general meetings or how to submit your proxy or need additional copies of this joint proxy statement/prospectus, the enclosed proxy card or voting instructions, you should contact: