e424b3

Filed Pursuant to Rule 424(b)(3)
File Number 333-172587

To the Shareholders of Ensco plc and the Stockholders of Pride International, Inc.:

The boards of directors of Ensco plc, referred to as Ensco, and Pride International, Inc., referred to as Pride, have each unanimously approved an agreement and plan of merger, which provides for a merger in which Pride will become a wholly owned subsidiary of Ensco. If the merger is completed, with exceptions for certain U.K. residents, for each share of Pride common stock, Ensco will issue and deliver to Pride stockholders 0.4778 American depositary shares, or ADSs, each whole ADS representing one Class A ordinary share of Ensco, nominal value $0.10 per share, and will pay $15.60 in cash. This exchange ratio and cash amount are fixed and will not be adjusted to reflect stock price changes prior to closing of the merger. Based on the closing price of Ensco ADSs on the New York Stock Exchange, referred to as the NYSE, on February 4, 2011, the last trading day before public announcement of the merger, the merger consideration represented approximately $41.60 in aggregate value for each share of Pride common stock. Based on the closing price of Ensco ADSs on the NYSE on April 21, 2011, the latest practicable trading day before the date of this joint proxy statement/prospectus, the merger consideration represented approximately $43.44 in aggregate value for each share of Pride common stock. The merger will be a taxable transaction for Pride stockholders for U.S. federal income tax purposes. A composite copy of the merger agreement, as amended, is attached as Annex A to this joint proxy statement/prospectus.

Holders of Pride common stock who are unable or fail to timely certify that they either are not U.K. residents or, if so, are U.K. resident “qualified investors” (within the meaning of Section 86(7) of the U.K. Financial Services and Markets Act 2000) will not receive Ensco ADSs as part of the merger consideration but will instead receive for each share of Pride common stock an amount of cash equal to the $15.60 cash component of the merger consideration plus an additional amount equal to the net proceeds of the sale by the exchange agent, Citibank, N.A., of 0.4778 Ensco ADSs.

Ensco and Pride will each hold a meeting of its shareholders or stockholders on May 31, 2011 in connection with the proposed merger. At the Ensco general meeting, Ensco shareholders will be asked to consider and vote on a proposal to approve the issuance and delivery of Ensco ADSs pursuant to the merger agreement. At the Pride special meeting, Pride stockholders will be asked to consider and vote on a proposal to adopt the merger agreement.

Ensco ADSs trade on the NYSE under the symbol “ESV.” We estimate that, based on the outstanding shares of Pride common stock and equity awards on March 31, 2011, immediately after the effective time of the merger former Pride stockholders will hold Ensco ADSs representing approximately 38% of the then-outstanding Ensco ADSs.

Your vote is very important. The merger cannot be completed unless (i) Ensco shareholders approve by ordinary resolution the issuance and delivery of Ensco ADSs pursuant to the merger agreement by the affirmative vote of the holders of at least a majority of the votes cast at a meeting at which one or more shareholders are present in person or by proxy who represent and vote at least a majority of the Class A ordinary shares (represented by ADSs) and are entitled to vote on April 11, 2011, the record date for the Ensco general meeting, and (ii) Pride stockholders adopt the merger agreement by the affirmative vote of the holders of at least a majority of the shares of Pride common stock outstanding and entitled to vote on April 11, 2011, the record date for the Pride special meeting. In addition, the obligations of Ensco and Pride to complete the merger are subject to the satisfaction or waiver of several other conditions set forth in the merger agreement.

The Ensco board of directors has unanimously approved the merger agreement and the transactions contemplated by the merger agreement and recommends that Ensco shareholders vote “FOR” the proposal to issue and deliver Ensco ADSs pursuant to the merger agreement. The Pride board of directors has unanimously approved the merger agreement and the transactions contemplated by the merger agreement and recommends that Pride stockholders vote “FOR” the proposal to adopt the merger agreement.

The accompanying joint proxy statement/prospectus contains important information about the merger, the merger agreement and the meetings of shareholders. This document is also a U.S. prospectus for the Ensco ADSs representing Class A ordinary shares that will be delivered pursuant to the merger agreement. We encourage you to read this joint proxy statement/prospectus carefully before voting, including the section entitled “Risk Factors” beginning on page 28.



Daniel W. Rabun		Louis A. Raspino
Chairman, President and Chief Executive Officer Ensco plc		President and Chief Executive Officer Pride International, Inc.

None of the Securities and Exchange Commission, any state securities regulatory authority or the U.K. Financial Services Authority, or FSA, has approved or disapproved of the merger or the securities to be issued under this joint proxy statement/prospectus or has passed upon the adequacy or accuracy of the disclosure in this joint proxy statement/prospectus. Any representation to the contrary is a criminal offense.

For the avoidance of doubt, this joint proxy statement/prospectus is not intended to be and is not a prospectus for the purposes of the Prospectus Rules made under Part 6 of the U.K. Financial Services and Markets Act 2000 (as set out in the U.K. FSA’s Handbook).

This joint proxy statement/prospectus is dated April 25, 2011, and is first being mailed to Ensco shareholders and Pride stockholders on or about April 28, 2011.

Ensco plc
6 Chesterfield Gardens
London England W1J 5BQ
+44 (0) 20 7659 4660

NOTICE OF GENERAL MEETING OF SHAREHOLDERS
TO BE HELD ON MAY 31, 2011

To the Shareholders of Ensco plc:

A general meeting of the shareholders of Ensco plc (“Ensco”) will be held at the registered office and headquarters of Ensco, 6 Chesterfield Gardens, London, W1J 5BQ, United Kingdom at 8:30 a.m. London time on May 31, 2011, for the following purposes:

1. to consider and vote on the proposal to approve the issuance and delivery of Ensco American depositary shares, or ADSs, pursuant to the Agreement and Plan of Merger, dated as of February 6, 2011 and as amended on March 1, 2011 (referred to as the merger agreement), by and among Ensco, ENSCO International Incorporated, a Delaware corporation and an indirect, wholly owned subsidiary of Ensco, ENSCO Ventures LLC, a Delaware limited liability company and an indirect, wholly owned subsidiary of Ensco, and Pride International, Inc., a Delaware corporation, as it may be amended from time to time (a composite copy of the merger agreement is attached as Annex A to the joint proxy statement/prospectus accompanying this notice); and

2. to transact any other business that may properly come before the general meeting or any adjournment or postponement of the general meeting.

Each resolution will be proposed as an ordinary resolution. Only Ensco shareholders of record at the close of business in London on April 11, 2011, the record date for the Ensco general meeting, are entitled to receive notice of, attend and vote at the Ensco general meeting or, subject to the Ensco Articles of Association, any adjournments or postponements of the Ensco general meeting.

The Ensco board of directors has unanimously approved the merger agreement and the transactions contemplated by the merger agreement and recommends that you vote “FOR” the proposal to approve the issuance and delivery of Ensco ADSs pursuant to the merger agreement, which is described in detail in the joint proxy statement/prospectus accompanying this notice.

YOUR VOTE IS IMPORTANT

Whether or not you plan to attend the general meeting, please submit a proxy or voting instruction card as soon as possible. Shareholders of record as of the close of business in London on April 11, 2011 are entitled to receive notice of, attend and vote at the Ensco general meeting or, subject to the Ensco Articles of Association, any adjournment or postponement of the Ensco general meeting. A list of all shareholders of record entitled to vote at the Ensco general meeting is on file at the registered office and headquarters of Ensco, 6 Chesterfield Gardens, London, W1J 5BQ, United Kingdom, and will be available for inspection at the Ensco general meeting. Changes to entries on the register after this time will be disregarded in determining the rights of any person to attend or vote at the Ensco general meeting. In accordance with provisions in the U.K. Companies Act 2006 and in accordance with the Ensco Articles of Association, a shareholder of record is entitled to appoint another person as his or her proxy to exercise all or any of his or her rights to attend and to speak and vote at the Ensco general meeting and to appoint more than one proxy in relation to the Ensco general meeting (provided that each proxy is appointed to exercise the rights attached to a different share or shares held by him or her). Such proxy need not be a shareholder of record.

If you received a proxy card or voting instruction card by mail, you may submit your proxy or voting instructions by completing, signing, dating and returning your proxy card or voting instruction card in the envelope provided. Holders of record and “street name” holders of Ensco ADSs may also instruct the ADS depositary c/o Broadridge how to vote by telephone at 1-800-690-6903 or via the Internet at www.proxyvote.com by following the instructions shown on the voting instruction card. Any shareholder of record attending the Ensco general meeting may vote in person. If you have returned a proxy card or voting

Pride International, Inc.
5847 San Felipe, Suite 3300
Houston, Texas 77057
+1 (713) 789-1400

NOTICE OF SPECIAL MEETING OF STOCKHOLDERS
TO BE HELD ON MAY 31, 2011

To the Stockholders of Pride International, Inc.:

A special meeting of the stockholders of Pride International, Inc., a Delaware corporation (“Pride”), will be held at the Hotel Granduca located at 1080 Uptown Park Blvd., Houston, Texas 77056 on May 31, 2011, at 8:00 a.m. Houston time for the following purposes:

1. to consider and vote on the proposal to adopt the Agreement and Plan of Merger, dated as of February 6, 2011 and as amended on March 1, 2011 (referred to as the merger agreement), by and among Ensco plc (“Ensco”), ENSCO International Incorporated, a Delaware corporation and an indirect, wholly owned subsidiary of Ensco, ENSCO Ventures LLC, a Delaware limited liability company and an indirect, wholly owned subsidiary of Ensco, and Pride, as it may be amended from time to time (a composite copy of the merger agreement is attached as Annex A to the joint proxy statement/prospectus accompanying this notice);

2. to consider and vote on any proposal to adjourn the special meeting to a later date or dates if necessary to solicit additional proxies if there are insufficient votes at the time of the special meeting to adopt the merger agreement; and

3. to transact any other business that may properly come before the special meeting or any adjournment or postponement of the special meeting by or at the direction of the board.

Only Pride stockholders of record at the close of business on April 11, 2011, the record date for the Pride special meeting, are entitled to notice of, and to vote at, the Pride special meeting and any adjournments or postponements of the Pride special meeting. For a period of 10 days prior to the special meeting, a complete list of stockholders of record entitled to vote at the special meeting will be available at our executive offices for inspection by stockholders during ordinary business hours for proper purposes.

The Pride board of directors has unanimously approved the merger agreement and the transactions contemplated by the merger agreement and unanimously recommends that you vote “FOR” the proposal to adopt the merger agreement, which is described in detail in the joint proxy statement/prospectus accompanying this notice, and “FOR” any proposal to adjourn the special meeting if necessary to solicit additional proxies.

YOUR VOTE IS IMPORTANT

Whether or not you plan to attend the special meeting, please submit a proxy as soon as possible.

If you received a proxy card by mail, you may submit your proxy by completing, signing, dating and returning your proxy card in the envelope provided. Submitting a proxy will assure that your vote is counted at the meeting if you do not attend in person. If your shares of Pride common stock are held in “street name” by your broker or other nominee, only that holder can vote your shares of Pride common stock and the vote cannot be cast unless you provide instructions to your broker or obtain a legal proxy from your broker. You should follow the directions provided by your broker regarding how to instruct your broker to vote your shares of Pride common stock. If you have returned a proxy card or otherwise voted, you may revoke prior instructions and cast your vote by following the procedures described in the joint proxy statement/prospectus.

ADDITIONAL INFORMATION

This joint proxy statement/prospectus incorporates by reference important business and financial information about Ensco and Pride from other documents filed with the SEC that are not included or delivered with this joint proxy statement/prospectus. See “Where You Can Find More Information; Incorporation by Reference.”

Documents incorporated by reference are available to Ensco shareholders and Pride stockholders without charge upon written or oral request. You can obtain any of these documents by requesting them in writing or by telephone from D.F. King & Co., Inc., Ensco’s proxy solicitor, or Innisfree M&A Incorporated, Pride’s proxy solicitor, at the following addresses and telephone numbers.


D.F. King & Co., Inc. 48 Wall Street, 22nd Floor New York, New York 10005 Shareholders Call Toll-Free at: 1-800-859-8509 Banks and Brokers Call Collect at: 1-212-269-5550 Email: ensco@dfking.com		Innisfree M&A Incorporated 501 Madison Avenue, 20th Floor New York, NY 10022 Shareholders Call Toll-Free at: 1-877-825-8772 Banks and Brokers Call Collect at: 1-212-750-5833

To receive timely delivery of the requested documents in advance of the applicable general or special meeting, you should make your request no later than May 23, 2011.

ABOUT THIS DOCUMENT

This document, which forms part of a registration statement on Form S-4 filed with the SEC by Ensco plc (File No. 333-172587), constitutes a prospectus of Ensco under Section 5 of the Securities Act of 1933, as amended, which we refer to as the Securities Act, with respect to the Class A ordinary shares represented by Ensco ADSs to be delivered pursuant to the merger agreement and certain sales of Ensco ADSs by an affiliate of the exchange agent for the merger and covers the effect of any failure to timely deliver certifications as to non-U.K. residency or “qualified investor” status within the meaning of Section 86(7) of the U.K. Financial Services and Markets Act 2000 by any record or beneficial owner of shares of Pride common stock. For the avoidance of doubt, this joint proxy statement/prospectus is not intended to be and is not a prospectus for the purposes of the Prospectus Rules made under Part 6 of the U.K. Financial Services and Markets Act 2000 (as set out in the U.K. FSA’s Handbook). This document also constitutes a notice of meeting and a proxy statement under Section 14(a) of the Securities Exchange Act of 1934, as amended, which we refer to as the Exchange Act, with respect to the general meeting of Ensco shareholders, at which Ensco shareholders will be asked to consider and vote on a proposal to approve the issuance and delivery of Ensco ADSs pursuant to the merger agreement, and with respect to the special meeting of Pride stockholders, at which Pride stockholders will be asked to consider and vote on a proposal to adopt the merger agreement.

You should rely only on the information contained or incorporated by reference into this document. Neither Ensco nor Pride has authorized anyone to provide you with information that is different from that contained in, or incorporated by reference into, this document. This document is dated April 25, 2011. You should not assume that the information contained in this document is accurate as of any date other than that date. You should not assume that the information incorporated by reference into this document is accurate as of any date other than the date of such incorporated document. Neither our mailing of this document to Ensco shareholders or Pride stockholders nor the delivery by Ensco of its ADSs pursuant to the merger agreement will create any implication to the contrary.

Unless otherwise stated herein, for purposes of determinations with respect to the number of Ensco ADSs to be issued in the merger and information derived therefrom, references to the number of outstanding shares of Pride common stock include shares subject to stock options and restricted stock units awarded under Pride incentive plans and shares subject to outstanding purchase rights under Pride’s Employee Stock Purchase Plan as of March 31, 2011, and are based on the assumption that all Pride stock option awards are exercised prior to or contemporaneously with completion of the merger.

QUESTIONS AND ANSWERS ABOUT THE MEETINGS

The following are some questions that Ensco shareholders and Pride stockholders may have regarding the proposals being considered at the Ensco general meeting and the Pride special meeting and brief answers to those questions. Ensco and Pride urge you to read carefully this entire joint proxy statement/prospectus, including the annexes, and the other documents to which this joint proxy statement/prospectus refers or incorporates by reference because the information in this section does not provide all the information that might be important to you. Unless stated otherwise, all references in this joint proxy statement/prospectus to Ensco are to Ensco plc, an English public limited company; all references to Pride are to Pride International, Inc., a Delaware corporation; all references to Merger Sub are to ENSCO Ventures LLC, a Delaware limited liability company and an indirect wholly owned subsidiary of Ensco; all references to Delaware Sub are to ENSCO International Incorporated, a Delaware corporation and an indirect wholly owned subsidiary of Ensco; and all references to the merger agreement are to the Agreement and Plan of Merger, dated as of February 6, 2011 and as amended on March 1, 2011, by and among Ensco, Delaware Sub, Merger Sub and Pride, a composite copy of which is attached as Annex A to this joint proxy statement/prospectus and is incorporated herein by reference, as it may be amended from time to time. References to “wholly owned subsidiaries” include a reference to subsidiaries owned directly or indirectly.


Q:	What is the proposed transaction?

A:	Ensco and Pride have entered into a merger agreement pursuant to which Merger Sub will merge with and into Pride, with Pride surviving the merger as an indirect wholly owned subsidiary of Ensco. Each issued and outstanding share of Pride common stock will be converted into the right to receive (i) 0.4778 Ensco ADSs and (ii) $15.60 in cash, with exceptions applicable to shares of Pride common stock held or deemed to be held by certain U.K. residents, as described under “The Merger Agreement — Merger Consideration.”

Q:	Why are Ensco and Pride proposing the merger?

A:	The boards of directors of Ensco and Pride believe that the merger will benefit Ensco’s shareholders and Pride’s stockholders by creating a top-tier global offshore drilling company given the complementary fleet composition, geographic scope and customer bases of the two companies. To review the reasons for the merger in greater detail, see “The Merger — Recommendation of the Ensco Board of Directors and Its Reasons for the Merger” beginning on page 63 and “The Merger — Recommendation of the Pride Board of Directors and Its Reasons for the Merger” beginning on page 66.

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

A:	Ensco shareholders are being asked to approve the issuance and delivery of Ensco ADSs pursuant to the merger agreement.

Pride stockholders are being asked to adopt the merger agreement.


Q:	When and where is the general meeting of the Ensco shareholders?

A:	The Ensco general meeting will be held at the registered office and headquarters of Ensco, 6 Chesterfield Gardens, London W1J 5BQ, United Kingdom at 8:30 a.m. London time on May 31, 2011.

Q:	When and where is the special meeting of the Pride stockholders?

A:	The Pride special meeting will be held on May 31, 2011 at 8:00 a.m. Houston time at the Hotel Granduca, located at 1080 Uptown Park Blvd., Houston, Texas 77056.

Q:	Who can attend and vote at the Ensco general meeting or the Pride special meeting?

A:	You are qualified to receive notice of, attend and vote at the Ensco general meeting if you owned Ensco Class A ordinary shares at the close of business in London on April 11, 2011, the record date for the Ensco general meeting. If you own Ensco ADSs representing Class A ordinary shares at the close of business in New York City on such date, whether directly or in “street name,” as described below, you are entitled to instruct the depositary for the Ensco ADSs on how to vote the Class A ordinary shares


	represented by your Ensco ADSs, which for purposes of this joint proxy statement/prospectus we refer to as voting your shares.

If you wish to attend the Ensco general meeting in person, representatives of the ADS depositary will be present at the Ensco general meeting to verify your right to attend, but you may not speak or vote at the Ensco general meeting unless you hold a valid proxy from the ADS depositary or you are a shareholder of record of Class A ordinary shares. Please bring the proxy and proof of your identity to the Ensco general meeting. If you are a “street name” holder of Ensco ADSs, you will need to bring evidence of your share ownership in the form of a currently-dated letter from your broker, bank, trust or other nominee and proof of your identity. On verification of such evidence, you will be admitted to the Ensco general meeting at the invitation of the Chairman, but may not speak or vote at the Ensco general meeting unless you hold a valid proxy from the ADS depositary.

All Pride stockholders of record as of the close of business on April 11, 2011, the record date for the Pride special meeting, are entitled to receive notice of, attend and vote at the Pride special meeting. If you are a “street name” holder of shares of Pride common stock and wish to attend the Pride special meeting, you will need to bring evidence of your share ownership in the form of a currently-dated letter from your broker, bank, trust or other nominee and proof of your identity. On verification of such evidence, you will be admitted to the Pride special meeting, but may not vote at the Pride special meeting unless you hold a proxy from the stockholder of record.


Q:	What vote is required to approve the proposals at the Ensco general meeting and the Pride special meeting?

A:	The approval by the Ensco shareholders of the issuance and delivery of Ensco ADSs pursuant to the merger agreement and the adoption by the Pride stockholders of the merger agreement are required for the consummation of the merger.

The approval of the Ensco shareholders for the issuance and delivery of Ensco ADSs pursuant to the merger agreement is being proposed as an ordinary resolution, which means that, assuming a quorum is present, the resolution will be approved for the purposes of the U.K. Companies Act 2006 if a majority of the votes cast are cast in favor of the resolution. Further, under the New York Stock Exchange, or NYSE, rules, the total amount of votes cast on the resolution must represent over 50% in interest of all securities entitled to vote.

Adoption of the merger agreement requires the affirmative vote of the holders of at least a majority of the outstanding shares of Pride common stock entitled to vote, and approval of the proposal to adjourn the special meeting if necessary to solicit additional proxies requires the affirmative vote of the holders of a majority of the shares present in person or represented by proxy at the special meeting and entitled to vote on the adjournment. Each share of Pride common stock is entitled to one vote on (1) the adoption of the merger agreement and (2) the approval of any proposal to adjourn the special meeting if necessary to solicit additional proxies.

Your vote is very important. You are encouraged to submit a proxy or voting instruction card as soon as possible.


Q:	What is the difference between a “shareholder of record,” a “holder of record of Ensco ADSs” and a “street name” holder?

A:	These terms describe how your shares are held. Holders of Ensco Class A ordinary shares registered directly in the holder’s name with Computershare Investor Services plc, its share registrar, and holders of Pride common stock registered directly in the holder’s name with BNY Mellon Shareowner Services, its transfer agent, are referred to as “shareholders of record” or “stockholders of record,” as applicable. Citibank, N.A. (London Branch) (or its nominee) is the registered holder of all outstanding Ensco Class A ordinary shares as of the date of this joint proxy statement/prospectus. Citibank, N.A. acts as the depositary with respect to the Ensco ADSs, each representing one Ensco Class A ordinary share on


	deposit with the depositary, pursuant to the terms and conditions of the deposit agreement among Citibank, Ensco and the holders of Ensco ADSs.

If you hold Ensco ADSs directly and your name appears on the register of the depositary, you are referred to as a “holder of record of Ensco ADSs,” and Citibank will, insofar as practicable and permitted under applicable law, the provisions of the deposit agreement and Ensco’s Articles of Association, vote Class A ordinary shares underlying your Ensco ADSs in accordance with your voting instructions if received timely.

If your shares are held in the name of a broker, bank, trust or other nominee as a custodian, you are a “street name” holder. Almost all Ensco shareholders are “street name” holders of Ensco ADSs, and almost all Pride stockholders are “street name” holders of shares of Pride common stock.


Q:	If my Ensco ADSs or shares of Pride common stock are held in “street name” by my broker or other nominee, will my broker or other nominee vote my Ensco ADSs or Pride common stock for me?

A:	Unless you instruct your broker how to vote your Ensco ADSs or Pride common stock, as applicable, your shares will NOT be voted.

Q:	What are the effects of abstentions and broker non-votes at the meetings?

A:	In connection with the Ensco general meeting, abstentions and broker non-votes will be considered in determining the presence of a quorum. However, because abstentions and broker non-votes are not considered votes cast under U.K. Companies Act 2006, they will not have any effect on the outcome of the vote with respect to the proposal to approve the issuance and delivery of Ensco ADSs pursuant to the merger agreement (assuming a quorum is present). Under NYSE rules, abstentions, but not broker non-votes, will be considered as votes cast for determining whether a sufficient number of votes have been cast on the resolution.

In connection with the Pride special meeting, abstentions and broker non-votes will be considered as present at the meeting for purposes of determining a quorum and will have the same effect as votes cast “AGAINST” the adoption of the merger agreement. Abstentions will have the same effect as votes cast “AGAINST” approval of any proposal to adjourn the special meeting if necessary to solicit additional proxies. Broker non-votes will have no effect on approval of that proposal.

An abstention occurs when a shareholder or stockholder abstains from voting (either in person or by proxy) on one or more of the proposals. Broker non-votes occur when a bank, broker or other nominee returns a proxy but does not have authority to vote on a particular proposal. You should therefore provide your broker or other nominee with instructions as to how to vote your Ensco ADSs or Pride common stock.


Q:	What happens if the merger is not completed?

A:	If the merger agreement is not adopted by Pride’s stockholders, if the issuance and delivery of Ensco ADSs pursuant to the merger agreement is not approved by Ensco’s shareholders or if the merger is not completed for any other reason, you will not receive any payment for your shares of Pride common stock in connection with the merger. Instead, Pride will remain an independent public company and Pride common stock will continue to be listed and traded on the NYSE. Under the merger agreement, Delaware Sub may be required to pay to Pride a termination fee of $260 million (less any fee previously paid by Delaware Sub) if the merger agreement is terminated under certain circumstances, and Pride may be required to pay to Ensco a termination fee of $260 million (less any fee previously paid by Pride) if the merger agreement is terminated under certain circumstances. In addition, the merger agreement requires each of Delaware Sub and Pride to pay a fee of $50 million in certain circumstances where the merger agreement is terminated by a party and the $260 million termination fee is not then payable to the other party, such as a failure to obtain shareholder approval under certain circumstances. See “The Merger Agreement — Termination Fees” beginning on page 128.


Q:	Does Pride intend to hold a 2011 annual meeting of stockholders?

A:	In light of the special meeting, Pride has cancelled the 2011 annual meeting of stockholders scheduled for May 19, 2011, and the 2011 annual meeting may not be held if the merger is completed in 2011. If the merger agreement is terminated or the proposal to adopt the merger agreement is not approved by Pride stockholders at the Pride special meeting, Pride intends to call an annual meeting of stockholders promptly thereafter. For a description of the procedures for submitting stockholder proposals to be included in the proxy materials for Pride’s 2011 annual meeting of stockholders, if held, see “Shareholder Proposals — Pride 2011 Annual Stockholder Meeting and Stockholder Proposals” beginning on page 191.

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 and in other documents incorporated by reference. You should read carefully the detailed description of the risks associated with the merger and the operations of Ensco after the merger described in “Risk Factors” beginning on page 28.

Q:	If I am a Pride stockholder, should I send in my stock certificates with my proxy card?

A:	NO. Please DO NOT send your Pride stock certificates with your proxy card. If the merger is approved, you will be sent written instructions for exchanging your stock certificates.

Q:	Are Pride stockholders entitled to appraisal rights?

A:	Yes. Holders of Pride common stock who do not vote in favor of the merger and who properly demand appraisal of their shares will be entitled to exercise appraisal rights in connection with the merger, and, if such rights are properly demanded and perfected and not withdrawn or lost and the merger is completed, such stockholders will be entitled to obtain payment for the judicially determined fair value of their shares of Pride common stock. For a detailed description of the exercise of appraisal rights, see “Appraisal Rights” beginning on page 130.

Q:	How does the Ensco board of directors recommend that Ensco shareholders vote?

A:	The Ensco board of directors has unanimously determined that the execution and delivery of the merger agreement is advisable and the transactions contemplated by the merger agreement, including the issuance and delivery of Ensco ADSs pursuant to the merger agreement, are in the best interests of Ensco and unanimously recommends that Ensco shareholders vote “FOR” the proposal to approve the issuance and delivery of Ensco ADSs pursuant to the merger agreement. For a more complete description of the recommendation of the Ensco board of directors, see “The Merger — Recommendation of the Ensco Board of Directors and Its Reasons for the Merger” beginning on page 63.

Q:	How does the Pride board of directors recommend that Pride stockholders vote?

A:	The Pride board of directors has unanimously determined that the merger agreement and the transactions contemplated by the merger agreement are advisable and in the best interests of Pride and its stockholders and unanimously recommends that Pride stockholders vote “FOR” the proposal to adopt the merger agreement and “FOR” any proposal to adjourn the special meeting if necessary to solicit additional proxies. For a more complete description of the recommendation of the Pride board of directors, see “The Merger — Recommendation of the Pride Board of Directors and Its Reasons for the Merger” beginning on page 66.

Q:	How will Ensco shareholders be affected by the merger and share issuance?

A:	After the merger, each Ensco shareholder will have the same number of Class A ordinary shares represented by Ensco ADSs that the shareholder held immediately prior to the merger. However, because Ensco will be delivering new Ensco ADSs to Pride stockholders in the merger, each outstanding Class A ordinary share represented by an Ensco ADS immediately prior to the merger will represent a smaller percentage of the aggregate number of Class A ordinary shares outstanding after the merger. As a result of the merger, each Ensco shareholder will own shares in a larger company with more assets and more outstanding shares.


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, as applicable and returning it in the enclosed postage-paid envelope or, if available, by submitting your proxy or voting instructions by telephone or through the Internet as soon as possible so that the Class A ordinary shares represented by your Ensco ADSs or your shares of Pride common stock will be represented and voted at the Ensco general meeting or Pride special meeting, as applicable.

Please refer to your proxy card, voting instruction card or the information forwarded by your broker or other nominee to see which voting options are available to you.

The Internet and telephone proxy submission procedures are designed to verify your holdings and to allow you to confirm that your instructions have been properly recorded.

The method by which you submit a proxy or voting instructions will in no way limit your right to vote at the Ensco general meeting or the Pride special meeting if you later decide to attend the meeting in person. If your shares of Pride common stock are held in the name of a broker or other nominee, you must obtain a proxy, executed in your favor, from the holder of record, to be able to vote at the Pride special meeting. If your Ensco ADSs are held in the name of a broker or other nominee, you must either cause the Class A ordinary shares represented by your Ensco ADSs to be withdrawn from the ADS depositary or obtain a proxy, executed in your favor, from the holder of record of your Ensco ADSs and obtain a proxy, executed in your favor from the ADS depositary, to be able to appear, speak and vote at the Ensco general meeting, although “street name” holders of Ensco ADSs are permitted to attend the Ensco general meeting at the invitation of the Chairman as described above.


Q:	How will my Ensco ADSs be voted?

A:	If you are a holder of record of Ensco ADSs, your name will appear on the register of Citibank as the ADS depositary, and Citibank, N.A. (London Branch) (or its nominee), as the registered holder of the Class A ordinary shares underlying your Ensco ADSs, will, insofar as practicable and permitted under applicable law, the provisions of the deposit agreement and the Ensco Articles of Association, vote the Class A ordinary shares underlying your Ensco ADSs in accordance with your voting instructions.

If you want the ADS depositary to vote your Ensco ADSs at the Ensco general meeting, you may provide your voting instructions to the ADS depositary c/o Broadridge via the Internet, by telephone or by sending in a completed voting instruction card, as described on the voting instruction card.

Voting instructions for Ensco ADSs must be received by the ADS depositary c/o Broadridge by the ADS voting cutoff time.

If the ADS depositary timely receives voting instructions that fail to specify the manner in which the ADS depositary is to vote the Class A ordinary shares represented by ADSs, the ADS depositary will vote as the Ensco board of directors recommends and, therefore, “FOR” the approval of the issuance and delivery of Ensco ADSs pursuant to the merger agreement.

If you are a “shareholder of record” of Ensco Class A ordinary shares, which as of the date of this joint proxy statement/prospectus is only Citibank as ADS depositary, you may vote your shares in person at the Ensco general meeting (any resolution put to vote at a general meeting shall be decided on a poll) or, in accordance with provisions in the U.K. Companies Act 2006 and in accordance with the Ensco Articles of Association, you are entitled to appoint another person as your proxy to exercise all or any of your rights to attend and to speak and vote at the Ensco general meeting and to appoint more than one proxy in relation to the Ensco general meeting (provided that each proxy is appointed to exercise the rights attached to a different share or shares held by you). Such proxy need not be a shareholder of record.


Q:	How will my shares of Pride common stock be voted?

A:	All shares of Pride common stock entitled to vote and represented by properly completed proxies received prior to the Pride special meeting, and not revoked, will be voted at the Pride special meeting as


		instructed on the proxies. If you properly complete, sign and return a proxy card, but do not indicate how your shares of Pride common stock should be voted on a matter, the shares of Pride common stock represented by your proxy will be voted as the Pride board of directors recommends and, therefore, “FOR” the adoption of the merger agreement and “FOR” any proposal to adjourn the special meeting if necessary to solicit additional proxies.


Q:	What if I am a “street name” holder of Ensco ADSs or shares of Pride common stock?

A:	If you are a “street name” holder of Ensco ADSs or shares of Pride common stock, you must provide the record holder of your shares with instructions on how to vote your shares. Please follow the voting instructions provided by your bank or broker. Please note that you may not vote shares held in street name by returning a proxy card or voting instruction directly to Ensco or Pride or by voting in person at the respective general or special meetings unless you provide a “legal proxy,” which you must obtain from your bank or broker.

If you are a “street name” holder of shares of Pride common stock and you do not instruct your broker on how to vote your shares, your broker may not give a proxy on or vote your shares on the proposal to adopt the merger agreement, which will have the same effect as a vote “AGAINST” adoption of the merger agreement.


Q:	When do holders of record and “street name” holders of Ensco ADSs have to submit their voting instructions to the ADS depositary?


A:	Voting instructions must be received by the ADS depositary by 11:59 p.m. New York City time on May 19, 2011 for employees and directors holding shares in Ensco benefit plans, and on May 24, 2011 for all other holders (the “ADS voting cutoff time”).

If the ADS depositary timely receives voting instructions that fail to specify the manner in which the ADS depositary is to vote the Class A ordinary shares represented by Ensco ADSs, the ADS depositary will vote in favor of the items set forth in such voting instructions. Class A ordinary shares represented by Ensco ADSs for which no timely voting instructions are received by the ADS depositary will not be voted.

If you are a “street name” holder, your broker, bank, trust or other nominee will arrange to provide materials and instructions for voting your Ensco ADSs. To allow sufficient time for voting by your broker, bank, trust or other nominee, your voting instructions must be received by the time specified in the materials provided by your broker, bank, trust or other nominee.

If you are a current or former Ensco employee who holds Ensco ADSs in the Ensco Savings Plan, you will receive voting instructions from the trustee of the plan for Ensco ADSs allocated to your account. If you fail to give voting instructions to the trustee, your Ensco ADSs will be voted by the trustee in the same proportion and direction as shares held by the trustee for which voting instructions were received. To allow sufficient time for voting by the trustee and administrator of the Ensco Savings Plan, your voting instructions for Ensco ADSs held in the plan must be received by the trustee and administrator by 11:59 p.m. New York City time on May 19, 2011.


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

A:	Yes.

If you are a holder of record of Ensco ADSs, you may revoke your voting instructions or change your vote at any time before the ADS voting cutoff date.

If your Ensco ADSs are held in an account at a broker or other nominee and you desire to change your vote, you should contact your broker or other nominee for instructions on how to do so before the applicable deadline.

If you are a holder of record of Ensco ADSs, you may revoke your voting instructions or otherwise change your vote by doing one of the following:


	•	sending a written notice of revocation to the ADS depositary c/o Broadridge that must be received before the ADS voting cutoff time, stating that you revoke your voting instructions;

	•	signing and submitting a later-dated voting instruction card that must be received by the ADS depositary c/o Broadridge before the ADS voting cutoff time in accordance with the instructions included in the voting instruction card; or

	•	if you voted electronically, by returning to www.proxyvote.com and changing your vote before the ADS voting cutoff time. Follow the same voting process, and your original vote will be superseded.

If you are a shareholder of record of Ensco Class A ordinary shares, you can do this in any of the three following ways:


	•	by sending a written notice to the Company Secretary of Ensco at the address set forth below, in time to be received before the Ensco general meeting, stating that you would like to revoke your proxy;

	•	by completing, signing and dating another proxy card and returning it by mail in time to be received before the Ensco general meeting, or by submitting a later dated proxy by the Internet in which case your later-submitted proxy will be recorded and your earlier proxy revoked; or

	•	by attending the meeting and voting in person. Simply attending the Ensco general meeting without voting will not revoke your proxy or change your vote.

If you are a stockholder of record of shares of Pride common stock, you can do this in any of the three following ways:


	•	by sending a written notice to the Secretary of Pride at the address set forth on the Pride notice of special meeting, in time to be received before the Pride special meeting, stating that you would like to revoke your proxy;

	•	by completing, signing and dating another proxy card and returning it by mail in time to be received before the Pride special meeting, or by submitting a later dated proxy via the Internet or telephone in which case your later-submitted proxy will be recorded and your earlier proxy revoked; or

	•	by attending the meeting and voting in person. Simply attending the Pride special meeting without voting will not revoke your proxy or change your vote.

If your shares of Pride common stock are held in an account at a broker or other nominee and you desire to change your vote, you should contact your broker or other nominee for instructions on how to do so.


Q:	What should I do if I receive more than one set of voting materials for the Ensco general meeting or the Pride special meeting?

A:	You may receive more than one set of materials for the Ensco general meeting or the Pride special meeting, including multiple copies of this joint proxy statement/prospectus and multiple proxy cards or voting instruction cards. For example, if you hold your Ensco ADSs or Pride common stock in more than one brokerage account, you will receive a separate proxy or voting instruction card for each brokerage account in which you hold Ensco ADSs or Pride common stock. If you are a holder of record and your Ensco ADSs or Pride common stock are registered in more than one name, you will receive more than one proxy or voting instruction card. Please complete, sign, date and return each proxy card and voting instruction card that you receive.

Q:	What happens if I hold both Ensco ADSs and shares of Pride common stock?

A:	You will receive separate proxy or voting instruction cards for each company and must complete, sign and date each proxy or voting instruction card and return each proxy or voting instruction card in the appropriate postage-paid envelope or, if available, by submitting a proxy or voting instructions by telephone or through the Internet for each company.

SUMMARY

The following is a summary that highlights information contained in this joint proxy statement/prospectus. This summary may not contain all of the information that is important to you. For a more complete description of the merger agreement and the transactions contemplated by the merger agreement, Ensco and Pride encourage you to carefully read this entire joint proxy statement/prospectus, including the attached annexes. In addition, Ensco and Pride encourage you to read the information incorporated by reference into this joint proxy statement/prospectus, which includes important business and financial information about Ensco and Pride that has been filed with the SEC. You may obtain the information incorporated by reference into this joint proxy statement/prospectus without charge by following the instructions in the section entitled “Where You Can Find More Information; Incorporation by Reference.”

The Companies

Ensco plc

Ensco plc is an English public limited company formed in 2009 in connection with its redomestication from Delaware to England. Its predecessor, ENSCO International Incorporated, was formed as a Texas corporation in 1975 and reincorporated in Delaware in 1987. In connection with its redomestication to England, each issued and outstanding share of common stock of ENSCO International Incorporated was converted into the right to receive one American depositary share (“ADS”), each representing one Class A ordinary share, nominal value $0.10 per share, of Ensco plc.

Ensco is a global offshore contract drilling company. As of March 15, 2011, its offshore rig fleet included 40 jackup rigs, five ultra-deepwater semisubmersible rigs and one barge rig. Additionally, it has three ultra-deepwater semisubmersible rigs under construction and recently announced that it has ordered the construction of two new ultra-premium, harsh environment jackup rigs. Ensco is one of the leading providers of offshore contract drilling services to the international oil and gas industry. Its customers include major integrated oil and natural gas companies, state-owned national oil companies and independent oil and natural gas companies. Its operations are concentrated in the geographic regions of Asia Pacific (which includes Asia, the Middle East and Australia), Europe and Africa, and North and South America.

Ensco’s ADSs are listed on the NYSE and trade under the symbol “ESV.”

Ensco’s registered office and principal executive offices are located at 6 Chesterfield Gardens, London, England W1J 5BQ and its telephone number is +44 (0) 20 7659 4660.

ENSCO Ventures LLC, referred to as Merger Sub, is a Delaware limited liability company and a wholly owned subsidiary of Ensco which was formed for the purpose of entering into the merger agreement. ENSCO International Incorporated, referred to as Delaware Sub, is Ensco’s predecessor and a wholly owned subsidiary of Ensco, which entered into the merger agreement for the purpose of agreeing to pay certain termination fees upon the occurrence of specified events in order to induce Pride to enter into the merger agreement for the benefit of Ensco.

Pride International, Inc.

Pride International, Inc. is a Delaware corporation formed in 2001 in connection with its reincorporation from Louisiana to Delaware as part of its acquisition of Marine Drilling Companies, Inc. Its predecessor, Pride Petroleum Services, Inc., was originally formed as a Louisiana corporation.

Pride operates a fleet of 26 mobile offshore drilling units, consisting primarily of floating rigs (semisubmersibles and drillships) that address deepwater drilling programs around the world. Pride has one of the youngest and most technologically advanced deepwater drilling fleets in the offshore industry, with five drillships, including three delivered since the beginning of 2010, six semisubmersible rigs and two managed, third party-owned deepwater rigs. Two additional Pride deepwater drillships are currently under construction with expected deliveries in 2011 and 2013. Pride’s fleet also includes six other semisubmersible rigs and seven

jackup rigs. Pride’s floating rig fleet operates primarily offshore Brazil and West Africa where the company has a long-standing presence.

Pride common stock is listed on the NYSE and trades under the symbol “PDE.”

Pride’s executive offices are located at 5847 San Felipe, Suite 3300, Houston, Texas 77057. Its telephone number at that address is (713) 789-1400.

The Merger (page 48)

Ensco and Pride have entered into the merger agreement pursuant to which Merger Sub will merge with and into Pride, with Pride surviving the merger as a wholly owned subsidiary of Ensco. As a result of the merger, each share of Pride common stock (other than dissenting shares as described in “Appraisal Rights,” shares held by Ensco, Pride or their respective subsidiaries and shares deemed to be held by or on behalf of certain U.K. residents as described in “The Merger Agreement — Merger Consideration — Effect on Securities”) will be converted into the right to receive 0.4778 Ensco ADSs and $15.60 in cash, as described under “The Merger Agreement — Merger Consideration.” On March 31, 2011, Ensco had outstanding approximately 143 million ADSs. Immediately following the completion of the merger, Ensco expects to have approximately 231 million ADSs outstanding based on the number of outstanding shares of Pride common stock. Ensco shareholders and Pride stockholders are expected to hold approximately 62% and 38%, respectively, of the Ensco ADSs outstanding immediately after the merger.

Based on the closing price of $54.41 per Ensco ADS on February 4, 2011, the last trading day before the public announcement of the execution and delivery of the merger agreement by Ensco and Pride, and $58.27 per Ensco ADS on April 21, 2011, the latest practicable trading day before the date of this joint proxy statement/prospectus, the aggregate value of the merger consideration to be received by Pride stockholders was approximately $7.6 billion and $8.0 billion, respectively. The $8.0 billion consists of approximately $2.9 billion to be paid in cash and approximately $5.1 billion to be paid through the issuance and delivery of approximately 87 million Ensco ADSs based on the number of outstanding shares of Pride common stock. The market value of the merger consideration ultimately received by Pride stockholders will depend on the closing price of Ensco ADSs on the day that the merger is consummated. See “Risk Factors — Risk Factors Relating to the Merger — Because the merger consideration is fixed and the market price of Ensco ADSs will fluctuate, Pride stockholders cannot be sure of the value of the merger consideration they will receive.”

A composite copy of the merger agreement, as amended, is attached as Annex A to this joint proxy statement/prospectus and is incorporated herein by reference. Ensco and Pride encourage you to read the merger agreement in its entirety because it is the legal document that governs the merger.

Recommendation of the Ensco Board of Directors (page 63)

The Ensco board of directors has unanimously determined that the execution and delivery of the merger agreement is advisable and the transactions contemplated by the merger agreement, including the issuance and delivery of Ensco ADSs pursuant to the merger agreement, are in the best interests of the Ensco shareholders, and has unanimously approved the merger agreement and the transactions contemplated by the merger agreement. The Ensco board of directors unanimously recommends that Ensco shareholders vote “FOR” the proposal to approve the issuance and delivery of Ensco ADSs pursuant to the merger agreement.

Recommendation of the Pride Board of Directors (page 66)

The Pride board of directors has unanimously determined that the merger agreement and the transactions contemplated by the merger agreement are advisable and in the best interests of Pride and its stockholders, and has unanimously approved the merger agreement and the transactions contemplated by the merger agreement. The Pride board of directors unanimously recommends that Pride stockholders vote “FOR” the proposal to adopt the merger agreement and “FOR” any proposal to adjourn the special meeting if necessary to solicit additional proxies.

Stockholders Entitled to Vote; Vote Required (pages 185 and 188)

Ensco

Ensco shareholders who owned Class A ordinary shares at the close of business on April 11, 2011, which is referred to as the Ensco record date, are qualified to receive notice of, attend and vote at the Ensco general meeting. On the Ensco record date, there were 143,429,203 Ensco Class A ordinary shares (represented by Ensco ADSs) outstanding and entitled to vote at the Ensco general meeting. Citibank, as the ADS depositary (or its nominee), is the registered holder of all outstanding Ensco Class A ordinary shares as of the date of this joint proxy statement/prospectus. If you own Ensco ADSs representing Class A ordinary shares at the close of business in New York City on the Ensco record date, whether directly or in “street name,” you are entitled to instruct the ADS depositary on how to vote the Class A ordinary shares represented by your Ensco ADSs, which for purposes of this joint proxy statement/prospectus we refer to as voting your shares.

Voting instructions must be received by the ADS depositary by 11:59 p.m. New York City time on May 19, 2011 for employees and directors holding shares in Ensco benefit plans, and on May 24, 2011 for all other holders (the “ADS voting cutoff time”).

Each Ensco Class A ordinary share is entitled to one vote on each matter to be voted on at the Ensco general meeting.

The approval of the issuance and delivery of Ensco ADSs pursuant to the merger agreement is being proposed as an ordinary resolution, which means that, assuming a quorum is present, the resolution will be approved for purposes of the U.K. Companies Act 2006 if a majority of the votes cast are cast in favor of the resolution. Further, under NYSE rules, the total amount of votes cast on the resolution must represent over 50% in interest of all securities entitled to vote. The chairman of the Ensco general meeting may also adjourn or postpone the meeting without notice other than announcement at the meeting for any purpose including to solicit additional proxies or voting instructions.

At the Ensco general meeting, holders of a majority of the outstanding Ensco Class A ordinary shares entitled to vote must be present, either in person or represented by proxy, to constitute a quorum. Abstentions and broker non-votes will be counted in determining whether a quorum is present at the Ensco general meeting. However, because abstentions and broker non-votes are not considered votes cast under English law, they will not have any effect on the outcome of the vote with respect to the proposal to approve the issuance and delivery of Ensco ADSs pursuant to the merger agreement (assuming a quorum is present). Under NYSE rules, abstentions, but not broker non-votes, will be considered as votes cast for determining whether a sufficient number of votes have been cast on the resolution.

An abstention occurs when a stockholder abstains from voting (either in person or by proxy) on one or more of the proposals. Broker non-votes occur when a bank, broker or other nominee returns a proxy but does not have authority to vote on a particular proposal.

Your vote is very important. You are encouraged to submit your proxy or voting instructions as soon as possible and in any event before the ADS voting cutoff time. If the ADS depositary timely receives voting instructions that fail to specify the manner in which the ADS depositary is to vote the Class A ordinary shares represented by Ensco ADSs, the ADS depositary will vote in favor of the items set forth in such voting instructions. Class A ordinary shares represented by Ensco ADSs for which no timely voting instructions are received by the ADS depositary will not be voted.

Pride

Pride stockholders who owned shares of Pride common stock at the close of business on April 11, 2011, which is referred to as the Pride record date, are entitled to vote at the Pride special meeting. On the Pride record date, there were 177,961,390 shares of Pride common stock outstanding and entitled to vote at the Pride special meeting, held by approximately 1,000 holders of record. Pride stockholders may cast one vote for each share of Pride common stock owned on the Pride record date.

At the Pride special meeting, holders of a majority of the total number of outstanding shares of Pride common stock entitled to vote must be present, either in person or represented by proxy, to constitute a quorum. Abstentions and broker non-votes will be counted in determining whether a quorum is present at the Pride special meeting.

The adoption of the merger agreement requires the affirmative vote of the holders of at least a majority of the outstanding shares of Pride common stock entitled to vote. The approval of any proposal to adjourn the special meeting if necessary to solicit additional proxies requires the affirmative vote of the holders of a majority of the shares present in person or represented by proxy at the special meeting and entitled to vote on the adjournment. Abstentions and broker non-votes will be considered as present at the meeting for purposes of determining a quorum and will have the same effect as votes cast “AGAINST” the adoption of the merger agreement. Abstentions will have the same effect as votes cast “AGAINST” approval of any proposal to adjourn the special meeting if necessary to solicit additional proxies. Broker non-votes will have no effect on approval of that proposal.

An abstention occurs when a stockholder abstains from voting (either in person or by proxy) on one or more of the proposals. A broker non-vote occurs when a bank, broker or other nominee returns a proxy but does not have authority to vote on a particular proposal.

Your vote is very important. You are encouraged to submit your proxy or voting instructions as soon as possible. If you do not indicate how your shares of Pride common stock should be voted on a matter, the shares of Pride common stock represented by your properly completed proxy will be voted as the Pride board of directors recommends and therefore “FOR” the adoption of the merger agreement and “FOR” the approval of any proposal to adjourn the special meeting if necessary to solicit additional proxies.

Opinions of Financial Advisors (pages 70 and 80)

Opinion of Deutsche Bank Securities Inc.

On February 5, 2011, Deutsche Bank Securities Inc., referred to as Deutsche Bank, financial advisor to Ensco, delivered to the board of directors of Ensco an oral opinion, subsequently confirmed in writing on February 6, 2011, to the effect that, as of the date of such opinion, and based upon and subject to the assumptions, limitations, qualifications and conditions described in Deutsche Bank’s opinion, the merger consideration comprised of $15.60 in cash and 0.4778 Ensco ADSs, each whole ADS representing one Ensco Class A ordinary share, to be paid in respect of each share of Pride common stock in the merger was fair, from a financial point of view, to Ensco.

The full text of Deutsche Bank’s written opinion, dated February 6, 2011, which sets forth, among other matters, the assumptions made, matters considered, and limitations, qualifications and conditions of the review undertaken by Deutsche Bank in connection with the opinion, is attached as Annex B to this proxy statement/prospectus and is incorporated herein by reference. The summary of the Deutsche Bank opinion set forth in this proxy statement/prospectus is qualified in its entirety by reference to the full text of the opinion. Deutsche Bank’s opinion was addressed to, and for the use and benefit of, the Ensco board of directors. The Deutsche Bank opinion is not a recommendation as to how any holder of Ensco ADSs or Ensco Class A ordinary shares should vote with respect to the merger. Deutsche Bank’s opinion is limited to the fairness, from a financial point of view, of the merger consideration to be paid in respect of each share of Pride common stock and does not address any other aspect of the merger. Deutsche Bank was not asked to, and Deutsche Bank’s opinion did not, address the fairness of the merger to the holders of any class of securities, creditors or other constituencies of Ensco. Deutsche Bank expressed no opinion as to the merits of the underlying decision by Ensco to engage in the merger or the relative merits of the merger as compared to any alternative transactions or business strategies. Nor did Deutsche Bank express an opinion as to how any holder of Ensco’s ADSs or Ensco Class A ordinary shares should vote with respect to the merger. Deutsche Bank did not express any view or opinion as to the fairness, financial or otherwise, of the amount or nature of any compensation payable to or to be received by any of the officers, directors, or employees of any party to the merger, or any class of such persons, in connection with the merger relative to the merger consideration. Deutsche Bank

expects to receive a transaction fee of $15 million, of which $3.75 million became payable upon the delivery of Deutsche Bank’s opinion (or would have become payable upon Deutsche Bank advising Ensco that it was unable to render an opinion) and the remainder is contingent upon consummation of the merger. Ensco may also pay Deutsche Bank an additional discretionary fee of up to $5 million, determined in Ensco’s sole discretion, to compensate Deutsche Bank based on the complexity of the transaction. For a more complete description, see “The Merger — Opinion of Deutsche Bank Securities Inc.” See also Annex B to this joint proxy statement/prospectus.

Opinion of Goldman, Sachs & Co.

At the meeting of the board of directors of Pride on February 6, 2011, Goldman, Sachs & Co, referred to as Goldman Sachs, delivered its oral opinion, subsequently confirmed in writing, that, as of February 6, 2011 and based upon and subject to the limitations and assumptions set forth therein, the per share consideration of $15.60 in cash and 0.4778 Ensco ADSs, each duly and validly issued against the deposit of an equal number of Ensco Class A ordinary shares, to be paid to the holders (other than Ensco and its affiliates) of the outstanding shares of Pride common stock pursuant to the merger agreement, dated February 6, 2011, was fair from a financial point of view to such holders. The full text of the written opinion of Goldman Sachs, dated February 6, 2011, which sets forth assumptions made, procedures followed, matters considered and limitations on the review undertaken in connection with the opinion, is attached as Annex C to this joint proxy statement/prospectus. Goldman Sachs provided its advisory services and its opinion for the information and assistance of the board of directors of Pride in connection with its consideration of the merger. The Goldman Sachs opinion does not constitute a recommendation as to how any holder of Pride common stock should vote with respect to the merger or any other matter. Goldman Sachs expects to receive a transaction fee currently estimated to be approximately $42 million (which is based on the closing price of Ensco ADSs and Pride net debt as of March 31, 2011), of which $5 million became payable upon execution of the engagement letter and the remainder is contingent upon consummation of the merger. For a more complete description, see “The Merger — Opinion of Goldman, Sachs & Co.” See also Annex C to this joint proxy statement/prospectus.

Directors and Executive Officers of Ensco After the Merger (page 94)

The directors and executive officers of Ensco prior to the merger will continue as the directors and executive officers of Ensco immediately after the merger, except that the merger agreement provides that Ensco shall take such actions as are necessary to expand the size of the Ensco board of directors and to appoint two non-employee members of the current Pride board of directors designated by Pride and reasonably acceptable to Ensco to fill such vacancies effective as of the effective time of the merger. Pride has not yet determined which of its current directors will be its designees on the Ensco board of directors as of the date of this joint proxy statement/prospectus. Upon determination of such designees by Pride, the Ensco Nominating, Governance and Compensation Committee will review the independence and qualifications of such candidates in accordance with Ensco’s Corporate Governance Policy and make a recommendation to the Ensco board of directors. Assuming a favorable recommendation, the Ensco board of directors will increase the size of the board by two and appoint the Pride designees to the newly-created vacancies in such classes of directors as the Ensco board may determine and provide that such directors shall stand for election for the remaining portion of the term of office for such classes at the next annual general meeting of shareholders for which a notice of the meeting has not been sent at the time of appointment.

In addition, it is currently expected that certain executive officers of Pride will become members of the Ensco executive management team following the merger. As of the date of this joint proxy statement/prospectus, it has not been determined which executive officers of Pride will join the Ensco executive management team, or what positions such executive officers will hold, following the merger.

Ownership of Ensco After the Merger (page 94)

Ensco will issue approximately 87 million Class A ordinary shares represented by Ensco ADSs pursuant to the merger based on the number of outstanding shares of Pride common stock. Immediately following the completion of the merger, Ensco expects to have approximately 231 million ADSs outstanding.

Ensco shareholders and Pride stockholders are expected to hold approximately 62% and 38%, respectively, of the Ensco ADSs outstanding immediately after the merger based on the same assumptions. Consequently, Pride stockholders, as a general matter, will have less influence over the management and policies of Ensco than they currently exercise over the management and policies of Pride.

Share Ownership of Directors and Executive Officers of Ensco

At the close of business on March 31, 2011, the directors and executive officers of Ensco and their affiliates beneficially owned and were entitled to vote 1,307,715 Ensco ADSs, collectively representing approximately less than 1% of the Ensco ADSs outstanding and entitled to vote on that date. The directors and executive officers of Ensco have each indicated that they expect to vote “FOR” the proposal to approve the issuance and delivery of Ensco ADSs in the merger.

Share Ownership of Directors and Executive Officers of Pride

At the close of business on March 31, 2011 the directors and executive officers of Pride and their affiliates beneficially owned and were entitled to vote 744,520 shares of Pride common stock, collectively representing less than 1% of the shares of Pride common stock outstanding and entitled to vote on that date. The directors and executive officers of Pride have each indicated that they expect to vote “FOR” the proposal to adopt the merger agreement and “FOR” any proposal to authorize the Pride board of directors, in its discretion, to adjourn the special meeting if necessary to solicit additional proxies.

Interests of the Pride Directors and Executive Officers in the Merger (page 90)

In considering the recommendation of the Pride board of directors with respect to the merger, Pride stockholders should be aware that the executive officers and directors of Pride have certain interests in the merger that may be different from, or in addition to, the interests of Pride stockholders generally. The Pride board of directors was aware of these interests and considered them, among other matters, in approving the merger agreement and making its recommendation that the Pride stockholders adopt the merger agreement.

These interests include certain Pride executive officers being entitled to receive specified severance and other benefits, following the effective time of the merger, including the following:


	•	Pride’s long-term incentive plans and applicable employment and award agreements generally provide for vesting of outstanding equity awards upon consummation of the merger;

	•	Pride’s executive officer employment agreements provide severance and other benefits in the case of qualifying terminations of employment in connection with or following the merger;

	•	Pride’s annual incentive plan provides for a payment of the pro-rated maximum bonus for the year in which the merger is completed; and

	•	certain of Pride’s executive officers participate in the Pride Supplemental Executive Retirement Plan, which provides for a lump sum cash payment in the event of termination of employment within two years after a change in control, including the merger; further, upon termination in certain circumstances, the executive and his spouse are entitled to retiree medical and dental benefits.

The merger agreement provides that Ensco will take such actions as are necessary to expand the size of the Ensco board of directors and to appoint two current non-employee members of the Pride board of directors designated by Pride and reasonably acceptable to Ensco to fill such vacancies effective as of the effective time of the merger. Such Pride designees will stand for election for the remaining portion of the term of office for their respective classes at the next annual general meeting of the shareholders of Ensco for which a notice of the meeting has not been sent at the time of the appointment. Pride has not yet determined which of its current directors will be its designees on the Ensco board of directors as of the date of this joint proxy statement/prospectus.

fiduciary liability insurance tail policies with respect to matters existing or occurring at or prior to the effective time of the merger.

Listing of Ensco ADSs; Delisting and Deregistration of Shares of Pride Common Stock (page 104)

Approval of the listing on the NYSE of the Ensco ADSs issuable pursuant to the merger agreement, subject to official notice of issuance, is a condition to each party’s obligation to complete the merger. Ensco has agreed to cause the Ensco ADSs issuable pursuant to the merger agreement to be approved for listing on the NYSE at or prior to the effective time of the merger, subject to official notice of issuance. If the merger is completed, shares of Pride common stock will be delisted from the NYSE and deregistered under the Exchange Act.

Appraisal Rights in the Merger (page 130)

Holders of Pride common stock who do not vote in favor of the merger will be entitled to exercise appraisal rights under the General Corporation Law of the State of Delaware, or DGCL, in connection with the merger, and, if such rights are properly demanded and perfected and not withdrawn or lost, such stockholders will be entitled to obtain payment for the judicially-determined fair value of their shares of Pride common stock if the merger is completed. See “Appraisal Rights.”

Conditions to the Completion of the Merger (page 114)

A number of conditions must be satisfied or, where legally permissible, waived before the proposed merger can be consummated. These include, among others:


	•	the approval by Ensco shareholders of the issuance and delivery of the Ensco ADSs pursuant to the merger agreement;

	•	the adoption of the merger agreement by Pride stockholders;

	•	the expiration or termination of the waiting period (and any extension thereof) applicable to the consummation of the merger under the HSR Act (which was satisfied on March 30, 2011);

	•	the absence of (a) any pending or threatened in writing claim, proceeding or action by an agency of the government of the United States seeking to restrain, prohibit or rescind any transactions contemplated by the merger agreement as an actual or threatened violation of any antitrust law or seeking to penalize a party for completing any such transaction and (b) any final or preliminary administrative order that remains in effect denying approval of or prohibiting the merger issued by a governmental entity with jurisdiction to enforce any applicable non-U.S. antitrust laws of a specified jurisdiction, in each case which is reasonably likely to require any competition actions, which are described in “The Merger Agreement — Additional Agreements — Efforts Related to Consents and Approvals of Governmental Entities and Third Parties”;

	•	the absence of any decree, order or injunction of a U.S. or non-U.S. court of competent jurisdiction prohibiting the merger;

	•	the effectiveness of the Form S-4 registration statement, of which this joint proxy statement/prospectus is a part, the effectiveness of a Form F-6 registration statement with respect to the Ensco ADSs, the absence of any stop order suspending the effectiveness of the Form S-4 or Form F-6, and the U.K. Listing Authority having approved a prospectus for residents of the United Kingdom, if such prospectus is required;

	•	the approval for listing on the NYSE of the Ensco ADSs to be delivered to the Pride stockholders pursuant to the merger agreement, subject to official notice of issuance; and

	•	the performance in all material respects of the covenants and agreements in the merger agreement by Ensco, Merger Sub, Delaware Sub and Pride, and the accuracy of the representations and warranties in


		the merger agreement of Ensco, Merger Sub, Delaware Sub and Pride, subject to the material adverse effect standard described below, with specified exceptions.

For more information regarding the conditions to the consummation of the merger and a complete list of such conditions, see “The Merger Agreement — Conditions to the Completion of the Merger.”

Regulatory Approvals Required for the Merger (page 94)

The merger is subject to review by the Antitrust Division of the U.S. Department of Justice, which is referred to as the Antitrust Division, under the HSR Act. Under the HSR Act, Ensco and Pride are required to make premerger notification filings and to await the expiration or early termination of the statutory waiting period (and any extension of the waiting period) prior to completing the merger. On February 28, 2011, Ensco and Pride each filed a Premerger Notification and Report Form with the Antitrust Division and the Federal Trade Commission, which is referred to as the FTC. On March 30, 2011, Ensco and Pride received notice from the Antitrust Division and the FTC granting early termination of the waiting period under the HSR Act.

The merger is also subject to antitrust review by government authorities in Brazil, which does not require governmental approval prior to the closing of the transaction.

No Solicitation and Change in Recommendation (page 118)

Under the merger agreement, Pride has agreed not to (and to not permit any of its officers, directors, employees, financial advisors, attorneys or other authorized representatives to) solicit, initiate, knowingly and intentionally encourage or facilitate, or negotiate, any competing acquisition proposal of Pride, provide information regarding Pride to a third party in connection with a competing acquisition proposal or release any such third party from any confidentiality or standstill agreement. However, before the adoption of the merger agreement by the Pride stockholders, Pride may, under certain circumstances, engage in negotiations with and provide information regarding Pride to a third party making an unsolicited, written acquisition proposal. Under the merger agreement, Pride is required to notify Ensco if it receives any competing acquisition proposal or request for information in connection with such a proposal.

Further, under the merger agreement, Ensco has agreed not to (and to not permit any of its officers, directors, employees, financial advisors, attorneys or other authorized representatives to) solicit, initiate, knowingly and intentionally encourage or facilitate, or negotiate, any competing acquisition proposal of Ensco, provide information regarding Ensco to a third party in connection with a competing acquisition proposal or release any such third party from any confidentiality or standstill agreement. However, before the approval of the issuance and delivery of Ensco ADSs pursuant to the merger agreement by the Ensco shareholders, Ensco may, under certain circumstances, engage in negotiations with and provide information regarding Ensco to a third party making an unsolicited, written acquisition proposal. Under the merger agreement, Ensco is required to notify Pride if it receives any competing acquisition proposal or request for information in connection with such a proposal.

Before receipt of the respective shareholder and stockholder approvals, after two business days’ prior notice to the other party and consideration of any proposed adjustments to the terms and conditions of the merger agreement, the board of directors of either Pride or Ensco may withdraw its recommendation or declaration of advisability of the merger agreement if a majority of the board of directors of such company determines in good faith that a failure to change its recommendation would reasonably be expected to be inconsistent with their fiduciary duties.

Termination of the Merger Agreement (page 126)

In general, the merger agreement may be terminated at any time prior to the effective time of the merger in the following ways:


	•	by mutual written consent of Ensco and Pride;


	•	by either Ensco or Pride if:


	•	the merger is not completed on or before February 3, 2012 (subject to certain exceptions in connection with the performance of obligations under the merger agreement);

	•	the Pride stockholders fail to adopt the merger agreement at the Pride special meeting, except that Pride will not be able to terminate the merger agreement if the failure to obtain stockholder approval is proximately caused by certain Pride breaches of the merger agreement; or

	•	the Ensco shareholders fail to approve the issuance and delivery of Ensco ADSs pursuant to the merger agreement at the Ensco general meeting, except that Ensco will not be able to terminate the merger agreement if the failure to obtain shareholder approval is proximately caused by certain Ensco breaches of the merger agreement;

	•	any injunction, order or decree of a court of competent jurisdiction or a governmental entity prohibiting or permanently enjoining the closing of the merger is in effect and has become final and nonappealable, provided that the party seeking to terminate the merger agreement shall have used its reasonable best efforts to remove such injunction, order or decree;


	•	by Pride if:


	•	Ensco, Delaware Sub or Merger Sub has breached or failed to perform its representations, warranties, covenants or other agreements in the merger agreement, which would give rise to the failure of a condition to Pride’s obligation to close the merger and is incapable of being cured prior to the termination date or is not cured by Ensco within 30 days following notice from Pride;

	•	prior to the adoption by Pride stockholders of the merger agreement, the Pride board of directors has received a competing superior proposal and has not violated the no solicitation provisions of the merger agreement with respect to such proposal, and Pride terminates the merger agreement in accordance with its terms (including considering any adjustments proposed by Ensco to amend the merger agreement during the three business day notice period prior to such termination and payment of the termination fee described below); or

	•	the Ensco board of directors withdraws or adversely changes its recommendation to its shareholders.


	•	by Ensco if:


	•	Pride has breached or failed to perform its representations, warranties, covenants or other agreements in the merger agreement, which would give rise to the failure of a condition to Ensco’s obligation to close the merger and is incapable of being cured prior to the termination date or is not cured by Pride within 30 days following notice from Ensco;

	•	prior to the approval by Ensco shareholders of the issuance and delivery of Ensco ADSs pursuant to the merger agreement, the Ensco board of directors has received a competing superior proposal and Ensco terminates the merger agreement in accordance with its terms (including considering any adjustments proposed by Pride to amend the merger agreement during the three business day notice period prior to such termination and payment of the termination fee described below); or

	•	the Pride board of directors withdraws or adversely changes its recommendation to its stockholders.

Termination Fees (page 128)

Under the merger agreement, Delaware Sub may be required to pay to Pride a termination fee of $260 million (less any fee previously paid by Delaware Sub) if the merger agreement is terminated under certain circumstances, and Pride may be required to pay to Ensco a termination fee of $260 million (less any fee previously paid by Pride) if the merger agreement is terminated under certain circumstances. In addition, the merger agreement requires each of Delaware Sub and Pride to pay a fee of $50 million, in certain circumstances where the merger agreement is terminated by a party and the $260 million termination fee is not then payable to the other party, such as a failure to obtain shareholder approval in certain circumstances.

Material U.S. Federal Income Tax Consequences of the Merger (page 95)

None of Ensco, the Ensco shareholders or Pride should be subject to the U.S. federal income tax as a result of the merger. Therefore, the discussion herein of the material U.S. federal income tax consequences of the merger is limited to the U.S. federal income tax consequences of the merger to the Pride stockholders.

For U.S. federal income tax purposes, the conversion of each issued and outstanding share of the Pride common stock into the right to receive Ensco ADSs and cash upon the consummation of the merger generally will be treated as an exchange of such share for the Ensco ADSs and cash. Therefore, the discussion of the material U.S. federal income tax consequences of the merger contained herein refers to an “exchange” rather than a “conversion” in describing the U.S. federal income tax consequences of the merger.

U.S. Holders

The exchange of shares of Pride common stock for Ensco ADSs and cash generally will be a taxable transaction for U.S. federal income tax purposes. A U.S. holder (as defined in “The Merger — Material U.S. Federal Income Tax Consequences of the Merger”) exchanging shares of Pride common stock in the merger will generally recognize gain or loss in an amount equal to the difference, if any, between (i) the sum of the value of the Ensco ADSs and cash received in the merger, including any cash received in lieu of fractional Ensco ADSs, and (ii) such holder’s adjusted tax basis in its Pride common stock exchanged therefor. Generally, such gain or loss will be capital gain or capital loss, respectively.

Non-U.S. Holders

Subject to certain exceptions, which are described below in “The Merger — Material U.S. Federal Income Tax Consequences of the Merger — Tax Consequences of the Merger to Pride Stockholders,” a non-U.S. holder (as defined below) generally will not be subject to U.S. federal income tax on gain realized, if any, on the exchange of shares of Pride common stock for Ensco ADSs and cash, including cash received in lieu of fractional Ensco ADSs.

Material U.K. Tax Consequences of the Merger (page 100)

Taxation of U.K. Pride Stockholders

Generally, U.K. resident Pride stockholders may realize a chargeable gain or an allowable loss for U.K. corporation tax or capital gains tax purposes (as the case may be) as a result of the merger, which will be treated as a disposal of their common stock in Pride for a consideration equal to the cash and the market value of the Ensco ADSs received by such Pride stockholders at that time.

Taxation of Non-U.K. Pride Stockholders

Generally, non-U.K. resident Pride stockholders should not be subject to either U.K. corporation tax or capital gains tax on a chargeable gain or allowable loss arising on a disposal of their common stock in Pride as a result of the merger, unless they carry on a trade in the U.K. through a permanent establishment in the U.K. or through a branch or agency in the U.K. for the purposes of U.K. corporation tax or capital gains tax respectively, and the stock is attributable to that permanent establishment, branch or agency. In those circumstances, the non-U.K. resident Pride stockholders may realize a chargeable gain or an allowable loss for U.K. corporation tax or capital gains tax purposes (as the case may be) as a result of the merger, which will be treated as giving rise to a disposal of their common stock in Pride for a consideration equal to the cash and the market value of the Ensco ADSs received by such Pride stockholders at that time.

No stamp duty or stamp duty reserve tax will be payable by Pride stockholders as a consequence of the merger.

Accounting Treatment (page 104)

Ensco will account for the merger using the acquisition method of accounting under U.S. generally accepted accounting principles, which are referred to as GAAP. As the accounting acquirer, Ensco’s assets and liabilities will remain at historical amounts.

In applying purchase accounting, Ensco will record the assets and liabilities of Pride at their estimated fair values at the closing date of the merger with the excess of the purchase price over the sum of such fair values recorded as goodwill. The purchase price is calculated using the estimated number of Ensco ADSs to be issued in the merger using the market price on the closing date of the merger, plus estimated cash consideration to be paid to Pride stockholders based on the number of shares of Pride common stock outstanding at the time of the merger and cash consideration of $15.60 per share and plus the estimated fair value of Pride stock options to be assumed by Ensco.

Payment of Dividends

Ensco

Ensco has paid regular quarterly cash dividends of $0.35 per share since the second quarter of 2010. Under the terms of the merger agreement, during the period before the closing of the merger, Ensco is prohibited from paying any dividends other than its regular quarterly dividends.

Pride

Pride does not currently pay quarterly cash dividends. Under the terms of the merger agreement, during the period before the closing of the merger, Pride is prohibited from paying any dividends.

Description of Debt Financing (page 134)

Ensco’s obligation to complete the merger is not conditioned upon its obtaining financing. Ensco anticipates that approximately $2.9 billion will be required to pay the aggregate cash portion of the merger consideration to the Pride stockholders. On February 6, 2011, Ensco entered into a bridge commitment letter with Deutsche Bank AG Cayman Islands Branch, or DBCI, Deutsche Bank Securities Inc. and Citigroup Global Markets Inc., or Citi. Pursuant to the commitment letter, DBCI and Citi committed to provide a $2.75 billion unsecured bridge term loan facility to fund a portion of the cash consideration in the merger. On March 17, 2011, in connection with its financing of the merger, Ensco issued two series of senior notes in a public offering: $1.0 billion aggregate principal amount of 3.25% senior notes due 2016 and $1.5 billion aggregate principal amount of 4.70% senior notes due 2021. Due to the issuance of the senior notes and the availability of cash on hand, which totaled approximately $3.4 billion as of March 31, 2011, Ensco terminated the bridge commitment letter on March 23, 2011. Ensco may seek additional sources of debt financing in the future to fund future operating and capital expenditures and for general corporate purposes. There can be no assurance that any additional sources of debt financing may be completed on commercially acceptable terms if at all.

Comparison of Rights of Pride Stockholders and Ensco Shareholders (page 160)

As a result of the merger, holders of Pride common stock will become holders of Ensco ADSs. Following the merger, Pride stockholders will have different rights as holders of Ensco ADSs than as stockholders of Pride due to the differences between English law and the DGCL and the different provisions of the governing documents of Pride and Ensco.

Litigation Relating to the Merger (page 105)

Following the announcement of the merger agreement, a number of putative stockholder class action complaints or petitions were filed against various combinations of Pride, Pride’s directors, Ensco, Delaware Sub, and Merger Sub in the Delaware Court of Chancery, the U.S. District Court for the Southern District of Texas, and in the state courts of Harris County, Texas. These lawsuits challenge the proposed merger and

generally allege, among other matters that the individual members of the Pride board of directors have breached their fiduciary duties owed to Pride’s stockholders by approving the proposed merger, failing to take steps to maximize value to Pride’s stockholders and failing to disclose material information concerning the proposed merger in the registration statement on Form S-4; that Pride, Ensco, Delaware Sub and Merger Sub aided and abetted such breaches of fiduciary duties; and that the merger agreement improperly favors Ensco and unduly restricts Pride’s ability to negotiate with rival bidders. These lawsuits generally seek, among other remedies, compensatory damages, declaratory and injunctive relief concerning the alleged fiduciary breaches, and injunctive relief prohibiting the defendants from consummating the merger. In addition, the plaintiffs in a derivative class action lawsuit related to Pride’s previously disclosed FCPA investigation filed an amendment to their petition adding claims related to the merger. In the amendment, the plaintiffs contend that the proposed merger was motivated by a desire to extinguish Pride’s alleged liability related to the derivative action, as well as other claims similar to those described above relating to the merger. The derivative class action lawsuit, as amended, has been consolidated with the other lawsuits in the state courts of Harris County, Texas.

Pride, Pride’s directors, Ensco, Delaware Sub and Merger Sub believe that the claims stated in the complaints relating to the merger are all without merit, and they intend to defend such actions vigorously.

Selected Historical Financial Data of Ensco

The following tables show Ensco’s selected historical consolidated financial data as of and for each of the fiscal years ended December 31, 2010, 2009, 2008, 2007 and 2006 and were derived from Ensco’s financial statements. You should read the following data in connection with “Management’s Discussion and Analysis of Financial Condition and Results of Operations” and the consolidated financial statements and the related notes thereto set forth in Ensco’s Annual Report on Form 10-K for the year ended December 31, 2010, which is incorporated herein by reference. See also the pro forma information set forth elsewhere in this joint proxy statement/prospectus regarding the proposed merger. Ensco’s historical results are not necessarily indicative of results to be expected in future periods.


	Year Ended December 31,
	2010			2009			2008			2007			2006
	(In millions, except per share amounts)

Statement of Income Data
Revenues	$	1,696.8		$	1,888.9		$	2,242.6		$	1,899.3		$	1,632.6
Operating expenses
Contract drilling (exclusive of depreciation)		768.1			709.0			736.3			613.4			519.8
Depreciation		216.3			189.5			172.6			165.5			155.0
General and administrative		86.1			64.0			53.8			59.5			44.6

Operating income		626.3			926.4			1,279.9			1,060.9			913.2
Other income (expense), net		18.2			8.8			(4.2	)		37.8			(5.9	)
Provision for income taxes		96.0			180.0			222.4			235.1			225.7

Income from continuing operations		548.5			755.2			1,053.3			863.6			681.6
Income from discontinued operations, net		37.4			29.3			103.4			135.3			93.6
Cumulative effect of accounting change, net		—			—			—			—			.6

Net income		585.9			784.5			1,156.7			998.9			775.8
Net income attributable to noncontrolling interests		(6.4	)		(5.1	)		(5.9	)		(6.9	)		(6.1	)

Net income attributable to Ensco	$	579.5		$	779.4		$	1,150.8		$	992.0		$	769.7

Earnings per share — basic
Continuing operations	$	3.80		$	5.28		$	7.32		$	5.80		$	4.42
Discontinued operations		.26			.20			.72			.91			.61

	$	4.06		$	5.48		$	8.04		$	6.71		$	5.03

Earnings per share — diluted
Continuing operations	$	3.80		$	5.28		$	7.31		$	5.78		$	4.40
Discontinued operations		.26			.20			.71			.91			.61

	$	4.06		$	5.48		$	8.02		$	6.69		$	5.01

Net income attributable to Ensco shares
Basic	$	572.1		$	769.7		$	1,138.2		$	984.7		$	765.4
Diluted	$	572.1		$	769.7		$	1,138.2		$	984.7		$	765.4
Weighted-average shares outstanding
Basic		141.0			140.4			141.6			146.7			152.2
Diluted		141.0			140.5			141.9			147.2			152.8
Cash dividends per share	$	1.075		$	.10		$	.10		$	.10		$	.10


	As of December 31,
	2010			2009			2008			2007			2006

Balance Sheet Data
Working capital	$	1,087.7		$	1,167.9		$	973.0		$	625.8		$	602.3
Total assets		7,051.5			6,747.2			5,830.1			4,968.8			4,334.4
Long-term debt, net of current portion		240.1			257.2			274.3			291.4			308.5
Ensco shareholders’ equity		5,959.5			5,499.2			4,676.9			3,752.0			3,216.0

Selected Historical Financial Data of Pride

The selected historical financial data of Pride as of December 31, 2010 and 2009, and for the years ended December 31, 2010, 2009 and 2008, were derived from Pride’s audited consolidated financial statements included in Pride’s Annual Report on Form 10-K for the year ended December 31, 2010. The selected historical financial data of Pride as of December 31, 2008, 2007 and 2006 and for the years ended December 31, 2007 and 2006 were derived from Pride’s consolidated financial information included in prior annual reports on Form 10-K. Pride has previously reclassified the historical results of operations of its former Latin America Land and E&P Services segments, three tender assist rigs, Pride’s former Eastern Hemisphere land rig operations, and Pride’s former mat-supported jackup business, to discontinued operations. See Note 2 to Pride’s audited consolidated financial statements in Pride’s Annual Report on Form 10-K for the year ended December 31, 2010. The selected historical financial data of Pride below should be read together with “Management’s Discussion and Analysis of Financial Condition and Results of Operations” and Pride’s audited consolidated financial statements and related notes included in Pride’s Annual Report on Form 10-K for the year ended December 31, 2010. See also the pro forma information set forth elsewhere in this joint proxy statement/prospectus regarding the proposed merger. Pride’s historical results are not necessarily indicative of results to be expected in future periods.


	Year Ended December 31,
	2010			2009			2008			2007			2006
	(In millions, except per share amounts)

Statement of Operations Data:
Revenues, excluding reimbursable revenues	$	1,431.5		$	1,563.5		$	1,664.7		$	1,294.2		$	885.9
Reimbursable revenues		28.6			30.7			37.9			34.8			22.7
Operating costs, excluding depreciation and amortization		871.9			828.3			766.5			618.6			587.9
Reimbursable costs		24.9			27.3			34.9			30.8			19.4
Depreciation and amortization		184.0			159.0			147.3			153.1			129.4
General and administrative, excluding depreciation and amortization		103.9			110.5			126.7			138.1			105.8
Department of Justice and Securities and Exchange Commission fines		—			56.2			—			—			—
Loss(gain) on sales of assets, net		0.2			(0.4	)		0.1			(29.8	)		(27.9	)

Earnings from operations		275.2			413.3			627.1			418.2			94.0
Interest expense, net of amounts capitalized		(13.4	)		(0.1	)		(20.0	)		(83.1	)		(89.0	)
Refinancing charges		(16.7	)		—			(2.3	)		—			—
Interest income		2.9			3.0			16.8			14.3			4.2
Other income(expense), net		4.0			(4.1	)		20.6			(2.7	)		2.5

Income from continuing operations before income taxes		252.0			412.1			642.2			346.7			11.7
Income taxes		(8.6	)		(71.8	)		(133.5	)		(86.9	)		(13.0	)

Income (loss) from continuing operations, net of tax	$	243.4		$	340.3		$	508.7		$	259.8		$	(1.3	)

Income (loss) from continuing operations per share:
Basic	$	1.37		$	1.93		$	2.95		$	1.54		$	(0.03	)
Diluted	$	1.37		$	1.92		$	2.89		$	1.51		$	(0.03	)
Shares used in per share calculations:
Basic		175.6			173.7			170.6			165.6			162.8
Diluted		176.2			174.0			175.2			178.1			162.8

Selected Unaudited Pro Forma Condensed Combined Financial Information

The following selected unaudited pro forma condensed combined statement of income data for the year ended December 31, 2010 have been prepared to give effect to the merger as if the merger had occurred on January 1, 2010. The unaudited pro forma condensed combined balance sheet data as of December 31, 2010 have been prepared to give effect to the merger as if the merger had occurred on December 31, 2010.

The following selected unaudited pro forma condensed combined financial information is not necessarily indicative of the results that might have occurred had the merger taken place on January 1, 2010 for statement of income purposes, and on December 31, 2010 for balance sheet purposes, and is not intended to be a projection of future results. Future results may vary significantly from the results reflected because of various factors, including those discussed in “Risk Factors.” The following selected unaudited pro forma condensed combined financial information should be read in conjunction with the “Unaudited Pro Forma Condensed Combined Financial Statements” and related notes included in this joint proxy statement/prospectus on page 135.


	Year Ended
	December 31, 2010
	(In millions,
	except per share data)

Pro Forma Condensed Combined Statement of Income Data:
Revenues	$	3,205
Contract drilling expense		1,665
Gross profit(1)		1,109
Income from continuing operations		774
Diluted earnings per share from continuing operations	$	3.35


(1)		Represents operating revenues less contract drilling expense and depreciation expense.


	As of
	December 31, 2010
	(In millions)

Pro Forma Condensed Combined Balance Sheet Data:
Working capital	$	982
Total assets		17,628
Long-term debt, net of current portion		4,844
Shareholders’ equity		10,630

Unaudited Comparative Per Share Data

The following table summarizes earnings per share data for Ensco and Pride for and as of the year ended December 31, 2010 on a historical basis and on a pro forma condensed combined basis giving effect to the merger. It has been assumed that the merger was completed on January 1, 2010 for statement of income purposes, and on December 31, 2010 for the book value per share data. The following information should be read in conjunction with the “Unaudited Pro Forma Condensed Combined Financial Statements” and related notes included elsewhere in this joint proxy statement/prospectus.


					Pride
	Ensco						Pro Forma
			Pro Forma				Combined
	Historical		Combined		Historical		Equivalent(1)

Basic earnings per share from continuing operations	$	3.80	$	3.36	$	1.37	$	1.61
Diluted earnings per share from continuing operations		3.80		3.35		1.37		1.60
Book value per share at period end(2)		41.68		46.42		25.69		22.18
Cash dividends declared per share		1.075		NA		—		NA


(1)		Pride pro forma combined equivalent data are calculated by multiplying the combined pro forma amounts by the stock exchange ratio of 0.4778. This calculation does not take into account the $15.60 cash portion of the merger consideration.

(2)		Historical book value per share is computed by dividing shareholders’ equity by the number of Ensco ADSs or Pride common shares outstanding. Ensco pro forma book value per share is computed by dividing pro forma shareholders’ equity by the pro forma number of Ensco ADSs outstanding.

Comparative Ensco and Pride Market Price and Dividend Data

Ensco ADSs are listed on the NYSE under the symbol “ESV.” Pride common stock is listed on the NYSE under the symbol “PDE.”

The following table presents closing prices for Ensco ADSs and Pride common stock on February 4, 2011, the last trading day before the public announcement of the execution of the merger agreement by Ensco and Pride, and April 21, 2011, the latest practicable trading day before the date of this joint proxy statement/prospectus. This table also presents the equivalent market value per share of Pride common stock on February 4, 2011 and April 21, 2011, as determined by multiplying the closing prices of Ensco ADSs on those dates by the stock exchange ratio of 0.4778, plus $15.60 in cash, without interest.

Although the stock exchange ratio is fixed, the market prices of Ensco ADSs and Pride common stock will fluctuate before the Ensco general meeting and the Pride special meeting and before the merger is completed and the market value of the merger consideration ultimately received by Pride stockholders will depend on the closing price of Ensco ADSs on the day the merger is consummated. See “Risk Factors — Risk Factors Relating to the Merger — Because the merger consideration is fixed and the market price of Ensco ADSs will fluctuate, Pride stockholders cannot be sure of the value of the merger consideration they will receive.”


	Ensco		Pride		Equivalent Per Share of
	ADSs		Common Stock		Pride Common Stock

February 4, 2011	$	54.41	$	34.39	$	41.60
April 21, 2011		58.27		43.19		43.44

The table below sets forth, for the calendar quarters indicated, the high and low sale prices per Ensco ADS and per share of Pride common stock on the NYSE. The table also shows the amount of cash dividends declared on Ensco ADSs and Pride common stock for the calendar quarters indicated.


	Ensco Common Stock /ADSs
					Cash Dividends
	High		Low		Declared

Fiscal Year Ended December 31, 2011
Second Quarter (through April 21, 2011)	$	59.90	$	54.54	$	—	⁽¹⁾
First Quarter		59.61		49.70		0.35
Fiscal Year Ended December 31, 2010
Fourth Quarter		53.93		43.08		0.35
Third Quarter		47.28		38.91		0.35
Second Quarter		52.32		33.33		0.35
First Quarter		46.98		37.45		0.025
Fiscal Year Ended December 31, 2009
Fourth Quarter		51.30		39.73		0.025
Third Quarter		43.14		32.26		0.025
Second Quarter		42.47		25.05		0.025
First Quarter		32.37		22.04		0.025


(1)		As of April 21, 2011, the Ensco board of directors had not yet declared its regular quarterly cash dividend of $0.35 per share for the second quarter 2011.

RISK FACTORS

In addition to the other information included or incorporated by reference in this joint proxy statement/prospectus, including the matters addressed under “Cautionary Statement Concerning Forward-Looking Statements,” Ensco shareholders and Pride stockholders should carefully consider the following risks before deciding how to vote. You also should consider the other information in this joint proxy statement/prospectus and the other documents incorporated by reference in this joint proxy statement/prospectus. See “Where You Can Find More Information; Incorporation by Reference.”

Risk Factors Relating to the Merger

Because the merger consideration is fixed and the market price of Ensco ADSs will fluctuate, Pride stockholders cannot be sure of the value of the merger consideration they will receive.

Upon consummation of the merger, each outstanding share of Pride common stock will be converted into the right to receive 0.4778 Ensco ADSs and $15.60 in cash. The number of Ensco ADSs to be issued pursuant to the merger agreement for each share of Pride common stock is fixed and will not change to reflect changes in the market price of Ensco ADSs. The market price of Ensco ADSs at the time of the merger may vary significantly from the market prices of Ensco ADSs on the date the merger agreement was executed, the date of this joint proxy statement/prospectus and the date on which Ensco shareholders or Pride stockholders vote on the merger.

In addition, the merger may not be completed until a significant period of time has passed after the shareholder meetings. Because the merger consideration will not be adjusted to reflect any changes in the market value of Ensco ADSs or Pride common stock, the market value of the Ensco ADSs issued in the merger and the Pride common stock surrendered in the merger cannot be determined at this time and may be higher or lower than the values of those shares on those earlier dates.

Stock price changes may result from a variety of factors that are beyond the control of Ensco and Pride, including:


	•	market reaction to the announcement of the merger and market assessment of the likelihood of the merger being consummated;

	•	changes in the respective businesses, operations or prospects of Ensco or Pride, including Ensco’s and Pride’s ability to meet earnings estimates;

	•	governmental or litigation developments or regulatory considerations affecting Ensco or Pride in particular or the offshore drilling industry in general;

	•	general business, market, industry or economic conditions;

	•	the worldwide supply/demand balance for oil and gas and the prevailing commodity price environment;

	•	the level of drilling and contracting activity of customers of Ensco and Pride; and

	•	other factors beyond the control of Ensco and Pride, including those described elsewhere in this “Risk Factors” section.

Neither party is permitted to “walk away” from the merger, terminate the merger agreement or resolicit the vote of its shareholders or stockholders solely because of changes in the market price of either party’s ADSs or common stock.

Directors and executive officers of Pride have certain interests that are different from those of Pride stockholders generally.

The executive officers of Pride who negotiated the terms of the merger agreement and the members of the Pride board of directors who approved the merger agreement have certain interests in the merger that may

be different from, or in addition to, the interests of Pride stockholders generally. These interests include the following:


	•	Pride’s long-term incentive plans and applicable employment and award agreements generally provide for vesting of outstanding equity awards upon consummation of the merger;

	•	Pride’s executive officer employment agreements provide severance and other benefits in the case of qualifying terminations of employment in connection with or following the merger;

	•	Pride’s annual incentive plan provides for a payment of the pro-rated maximum bonus for the year in which the merger is completed; and

	•	certain of Pride’s executive officers participate in the Pride Supplemental Executive Retirement Plan, which provides for a lump sum cash payment in the event of termination of employment within two years after a change in control, including the merger; further, upon termination in certain circumstances, the executive and his spouse are entitled to retiree medical and dental benefits.

The merger agreement provides that Ensco will take such actions as are necessary to expand the size of the Ensco board of directors and to appoint two current non-employee members of the Pride board of directors designated by Pride and reasonably acceptable to Ensco to fill such vacancies effective as of the effective time of the merger. Such Pride designees will stand for election for the remaining portion of the term of office for their respective classes at the next annual general meeting of the shareholders of Ensco. Pride has not yet determined which of its current directors will be its designees on the Ensco board of directors as of the date of this joint proxy statement/prospectus.

The merger agreement also provides for indemnification in favor of the current and former directors and officers of Pride and its subsidiaries and for the purchase of directors’ and officers’ liability insurance and fiduciary liability insurance tail policies with respect to matters existing or occurring at or prior to the effective time of the merger.

For a discussion of the interests of directors and executive officers in the merger, see “The Merger — Interests of the Pride Directors and Executive Officers in the Merger.”

The merger agreement contains provisions that limit each party’s ability to pursue alternatives to the merger, could discourage a potential competing acquirer of either Pride or Ensco from making a favorable alternative transaction proposal and, in certain circumstances, could require Delaware Sub or Pride to pay a termination fee of $260 million to the other.

Under the merger agreement, Delaware Sub or Pride may be required to pay to Pride or Ensco, respectively, a termination fee of $260 million if the merger agreement is terminated under certain circumstances. If such a termination fee is payable, the payment of this fee could have material and adverse consequences to the financial condition and operations of the company making such payment.

Under the merger agreement, Ensco and Pride are restricted from entering into alternative transactions. Unless and until the merger agreement is terminated, subject to specified exceptions (which are discussed in more detail in “The Merger Agreement — Termination of the Merger Agreement”), both Ensco and Pride are restricted from soliciting, initiating, knowingly and intentionally encouraging or facilitating, or negotiating, any inquiry, proposal or offer for a competing acquisition proposal with any person. Additionally, under the merger agreement, in the event of a potential change by the board of directors of either party of its recommendation with respect to the merger, such party must provide the other with two business days to propose an adjustment to the terms and conditions of the merger agreement. Ensco and Pride may terminate the merger agreement and enter into an agreement with respect to a superior proposal only if specified conditions have been satisfied, including compliance with the no solicitation and termination provisions of the merger agreement. These provisions could discourage a third party that may have an interest in acquiring all or a significant part of Ensco or Pride from considering or proposing that acquisition, even if such third party were prepared to pay consideration with a higher per share cash or market value than the market value proposed to be received or realized in the merger, or might result in a potential competing acquirer proposing

to pay a lower price than it would otherwise have proposed to pay because of the added expense of the termination fee that may become payable in certain circumstances. As a result of these restrictions, neither Ensco nor Pride may be able to enter into an agreement with respect to a more favorable alternative transaction without incurring potentially significant liability to the other.

Ensco and Pride may be unable to obtain the regulatory clearances and approvals required to complete the merger or, in order to do so, Ensco and Pride may be required to comply with material restrictions or conditions.

The merger is subject to review by governmental entities under non-U.S. antitrust or competition merger control statutes. Ensco and Pride have also filed the required notices with antitrust and competition authorities in Brazil. The closing of the merger is also subject to the condition that there be no pending or threatened claim, proceeding or action by a U.S. governmental entity seeking to restrain, prohibit or rescind any transactions contemplated by the merger agreement as an actual or threatened violation of antitrust law or seeking to penalize a party for completing any such transaction, and no final or preliminary administrative order denying approval or prohibiting the merger issued by antitrust and competition authorities in Brazil, in each case that would require either Ensco or Pride to dispose of assets or limit its freedom of action, except for such dispositions or limits that, in the reasonable good faith judgment of both Ensco and Pride, do not and are not reasonably likely to have a material adverse effect on Ensco or Pride, respectively. Ensco and Pride can provide no assurance that all required regulatory approvals will be obtained or that these approvals will not contain terms, conditions or restrictions, such as the disposition of assets or limitations on freedom of action, that would be detrimental to the combined company after the effective time of the merger.

Additionally, notwithstanding the parties receiving early termination of the statutory waiting period under the HSR Act, governmental authorities could seek to block or challenge the merger as they deem necessary or desirable in the public interest at any time, including after completion of the merger. In addition, in some jurisdictions, a competitor, customer or other third party could initiate a private action under such jurisdiction’s antitrust laws challenging or seeking to enjoin the merger, before or after it is completed. Ensco or Pride may not prevail and may incur significant costs in defending or settling any action under the antitrust laws.

Any delay in completing the merger may substantially reduce the benefits expected to be obtained from the merger.

In addition to obtaining the required governmental clearances and approvals, the merger is subject to a number of other conditions beyond the control of Pride and Ensco that may prevent, delay or otherwise materially adversely affect its completion. See “The Merger Agreement — Conditions to the Completion of the Merger.” Ensco and Pride cannot predict whether or when the conditions required to complete the merger will be satisfied. The requirements for obtaining the required clearances and approvals could delay the effective time of the merger for a significant period of time or prevent it from occurring. Any delay in completing the merger may materially adversely affect the synergies and other benefits that Ensco and Pride expect to achieve if the merger and the integration of their respective businesses are completed within the expected timeframe.

Ensco’s future results of operations could be adversely affected if the goodwill recorded in the merger subsequently requires impairment.

When Ensco acquires a business, generally goodwill is recorded as an asset on its balance sheet and is equal to the excess amount it pays for the business, including the fair value of liabilities assumed, over the fair value of the tangible and identified intangible assets of the business it acquires. Financial Accounting Standards Board Accounting Standards Codification, or FASB ASC, Topic 350 requires that goodwill and other intangible assets that have indefinite useful lives not be amortized, but instead be tested at least annually for impairment, and that intangible assets that have finite useful lives be amortized over their useful lives. FASB ASC Topic 350 provides specific guidance for testing goodwill and other indefinite lived intangible assets for impairment. FASB ASC Topic 350 requires management to make certain estimates, judgments and assumptions when allocating goodwill to reporting units and determining the fair value of those reporting units, including, among other things, appropriate risk-adjusted discount rates, as well as future industry

conditions and operations, expected utilization, day rates, expense levels, capital requirements and terminal values for each of the rigs. Absent any impairment indicators, Ensco performs its impairment tests annually during the fourth quarter. Any future impairments would negatively impact its results of operations for the period in which the impairment is recognized.

Ensco and Pride will incur substantial transaction and merger-related costs in connection with the merger.

Ensco and Pride expect to incur a number of non-recurring transaction and merger-related costs associated with completing the merger, combining the operations of the two companies and achieving desired synergies. These fees and costs will be substantial. Additional unanticipated costs may be incurred in the integration of the businesses of Ensco and Pride. Although it is expected that the elimination of certain duplicative costs, as well as the realization of other efficiencies related to the integration of the two businesses, will offset the incremental transaction and merger-related costs over time, this net benefit may not be achieved in the near term, or at all.

The merger agreement places certain restrictions on the conduct of the business of each of Ensco and Pride prior to completion of the merger or termination of the merger agreement, which could adversely affect each company’s ability to pursue beneficial business opportunities.

The merger agreement places certain restrictions on the conduct of each of Ensco’s and Pride’s businesses prior to the completion of the merger or the termination of the merger agreement. Such restrictions, the waiver of which is subject to the consent of the other party, may prevent Ensco and Pride from making certain acquisitions, taking certain other specified actions or otherwise pursuing business opportunities during the pendency of the merger (see “The Merger Agreement — Conduct of Business Pending the Merger” for a description of the restrictive covenants applicable to each of Ensco and Pride).

Ensco’s shareholders and Pride’s stockholders will have their ownership positions diluted by the merger.

The merger will dilute the ownership position of the current shareholders of Ensco. Ensco will issue approximately 87 million Class A ordinary shares represented by Ensco ADSs based on the number of outstanding shares of Pride common stock. As a result, Ensco shareholders and Pride stockholders are expected to hold approximately 62% and 38%, respectively, of the combined company’s ADSs outstanding immediately after the merger.

Pride stockholders will have a reduced ownership and voting interest after the merger and will exercise less influence over management.

Pride stockholders currently have the right to vote in the election of the board of directors of Pride and on other matters affecting Pride. When the merger occurs, each Pride stockholder that receives Ensco ADSs will become a shareholder of Ensco with a percentage ownership of the combined organization that is much smaller than the stockholder’s percentage ownership of Pride. It is expected that the former stockholders of Pride as a group will own approximately 38% of the outstanding Ensco ADSs immediately after the merger. Because of this, Pride stockholders will have less influence on the management and policies of Ensco than they now have on the management and policies of Pride.

The Ensco ADSs to be received by Pride stockholders upon the completion of the merger will have different rights from shares of Pride common stock.

Upon completion of the merger, Pride stockholders will no longer be stockholders of Pride, a Delaware corporation, but will instead become holders of ADSs of Ensco, an English public limited company, and their rights as beneficial holders of Class A ordinary shares will be governed by English law, the Ensco Articles of Association and the deposit agreement governing the terms of the Ensco ADSs. English law and the terms of the Ensco Articles of Association and ADS deposit agreement may be materially different than Delaware law and the terms of Pride’s certificate of incorporation and bylaws, which currently govern the rights of Pride

stockholders. Please see “Description of Class A Ordinary Shares of Ensco,” “Description of American Depositary Shares of Ensco” and “Comparison of Rights of Pride Stockholders and Ensco Shareholders” for a discussion of the different rights associated with Ensco ADSs.

Ensco and Pride may have difficulty attracting, motivating and retaining executives and other employees in light of the merger.

Uncertainty about the effect of the merger on Ensco and Pride employees may have an adverse effect on Ensco and Pride and consequently the combined company. This uncertainty may impair Ensco’s and Pride’s ability to attract, retain and motivate personnel until the merger is completed. Employee retention may be particularly challenging during the pendency of the merger, as employees may experience uncertainty about the move of Ensco’s U.S. headquarters from Dallas to Houston and their future roles with the combined company. If employees of Ensco or Pride depart because of issues relating to the uncertainty and difficulty of integration or a desire not to become employees of the combined company, the combined company’s ability to realize the anticipated benefits of the merger could be reduced.

The date that Pride stockholders will receive their merger consideration is uncertain.

The completion of the merger is subject to the stockholder and governmental approvals described in this joint proxy statement/prospectus and the satisfaction or waiver of certain other conditions. While we currently expect to complete the merger during the second calendar quarter of 2011, such date could be later than expected due to delays in receiving such approvals. Accordingly, we cannot provide Pride stockholders a definitive date on which they will receive the merger consideration.

Pending litigation against Pride and Ensco could result in an injunction preventing the consummation of the merger or may adversely affect Ensco’s business, financial condition or results of operations following the merger.

In connection with the merger, various lawsuits have been filed in the Delaware Court of Chancery, the U.S. District Court for the Southern District of Texas and in the District Courts of Harris County, Texas, against Pride, its directors and Ensco and/or certain of its subsidiaries alleging violations of various fiduciary duties in approving the merger and that Ensco and/or Pride aided and abetted such alleged violations. Among other remedies, the plaintiffs seek to enjoin the merger. While Ensco and Pride believe these suits are without merit and intend to vigorously defend against such claims, the outcome of any such litigation is inherently uncertain. All applicable insurance policies may not provide sufficient coverage for the cost of defense and claims under these lawsuits, and certain of the defendants’ rights of indemnification with respect to these lawsuits will continue after the completion of the merger. The defense or settlement of any lawsuit or claim that remains unresolved at the time the merger closes may adversely affect Ensco’s business, financial condition or results of operations.

Failure to complete the merger could negatively affect the trading prices of Ensco ADSs and Pride common stock and the future business and financial results of Ensco and Pride.

Completion of the merger is not assured and is subject to risks, including the risks that approval of the transaction by shareholders and stockholders of Ensco and Pride or by governmental agencies is not obtained or that certain other closing conditions are not satisfied. If the merger is not completed, it could negatively affect the trading prices of Ensco ADSs and Pride common stock and the future business and financial results of Ensco and Pride, and each of them will be subject to several risks, including the following:


	•	having to pay certain significant costs relating to the merger, including in certain circumstances a termination fee of $260 million or $50 million as described in “The Merger Agreement — Termination Fees;”

	•	negative reactions from the financial markets, including declines in the price of Pride common stock or Ensco ADSs due to the fact that current prices may reflect a market assumption that the merger will be completed;


	•	the attention of management of Ensco and Pride will have been diverted to the merger rather than each company’s own operations and pursuit of other opportunities that could have been beneficial to that company; and

	•	resulting negative customer perception could adversely affect the ability of Ensco and Pride to compete for, or to win, new and renewal business in the marketplace.

Risk Factors Relating to the Combined Company Following the Merger

The existing businesses of Ensco and Pride are both subject to significant risks. The risks affecting Ensco’s current business are described in Item 1A of its Annual Report on Form 10-K for the year ended December 31, 2010, which are incorporated herein by reference. The risks affecting Pride’s business are described in Item 1A of its Annual Report on Form 10-K for the year ended December 31, 2010, which is incorporated herein by reference. We anticipate that these risks will continue to apply to Ensco’s and Pride’s businesses following the merger. In addition, the future business and operations of the combined company may be affected by the following additional risks.

The success of the business of the combined company largely depends on the level of activity in the oil and gas industry which can be significantly affected by volatile oil and natural gas prices.

The success of business of the combined company largely depends on the level of activity in offshore oil and natural gas exploration, development and production. Oil and natural gas prices, and market expectations of potential changes in these prices, may significantly affect the level of drilling activity. An actual decline, or the perceived risk of a decline, in oil and/or natural gas prices could cause oil and gas companies to reduce their overall level of activity or spending, in which case demand for the services of the combined company may decline and revenues may be adversely affected through lower rig utilization and/or lower day rates.

Numerous factors may affect oil and natural gas prices and the level of demand for the services of the combined company, including:


	•	demand for oil and natural gas;

	•	the ability of OPEC to set and maintain production levels and pricing;

	•	the level of production by non-OPEC countries;

	•	U.S. and non-U.S. tax policy;

	•	laws and government regulations that limit, restrict or prohibit exploration and development of oil and natural gas in various jurisdictions;

	•	advances in exploration and development technology;

	•	disruption to exploration and development activities due to hurricanes and other severe weather conditions and the risk thereof;

	•	the worldwide military or political environment, including uncertainty or instability resulting from civil unrest, political demonstrations, mass strikes or an escalation or additional outbreak of armed hostilities or other crises in oil or natural gas producing areas of the Middle East, North Africa or other geographic areas in which the combined company may operate, or acts of terrorism; and

	•	global economic conditions.

Continued effects of the economic recession could lead to a decline in demand for crude oil and natural gas. Further slowdowns in economic activity would likely reduce worldwide demand for energy and result in an extended period of lower crude oil and natural gas prices. In addition, continued hostilities in the Middle East and Africa and the occurrence or threat of terrorist attacks against the United States or other countries could further the downturn in the economies of the United States and those of other countries. Moreover, even during periods of high commodity prices, customers may cancel or curtail their drilling programs, or reduce their levels of capital expenditures for exploration and production for a variety of reasons, including their lack

of success in exploration efforts. These factors could cause the combined company’s revenues and margins to decline, decrease daily rates and utilization of our rigs and limit our future growth prospects. Any significant decrease in daily rates or utilization, particularly for high-specification drillships or semisubmersible rigs, could materially reduce the combined company’s revenues and profitability.

The offshore contract drilling industry historically has been cyclical, with periods of low demand and excess rig availability that could result in adverse effects on the business of the combined company.

Operating results in the offshore contract drilling industry historically have been very cyclical and primarily are related to the demand for drilling rigs and the available supply of drilling rigs. Demand for rigs is directly related to the regional and worldwide levels of offshore exploration and development spending by oil and gas companies, which is beyond the control of the combined company. Offshore exploration and development spending may fluctuate substantially from year-to-year and from region-to-region. A decline in demand for drilling rigs or an increase in drilling rig supply could adversely affect the financial position, operating results and cash flows of the combined company.

The supply of offshore drilling rigs has increased in recent years. There are 62 new jackups, 21 semisubmersible rigs and 41 drillships, including those of Ensco and Pride, reported to be on order or under construction with delivery expected by the end of 2013. This represents an increase in the respective total worldwide fleets of 13% for jackups, 10% for semisubmersibles and 64% for drillships. Not all of the rigs currently under construction have been contracted for future work upon delivery. There are no assurances that the market in general or a geographic region in particular will be able to fully absorb the supply of new rigs in future periods.

The increase in supply of offshore drilling rigs during 2011 and future periods could result in an oversupply of offshore drilling rigs and could cause a decline in utilization and/or day rates, a situation which could be exacerbated by a decline in demand for drilling rigs. Lower utilization and/or day rates in one or more of the regions in which the combined company will operate could adversely affect the revenues, utilization and profitability of the combined company.

Certain events, such as limited availability or non-availability of insurance for certain perils in some geographic areas, rig loss or damage due to hurricanes, fire, explosion, blowouts, craterings, punchthroughs, wild wells, oil spills and leaks or spills of hazardous materials and other operational events, may impact the supply of rigs in a particular market and cause rapid fluctuations in utilization and day rates.

Future periods of reduced demand and/or excess rig supply may require the combined company to idle additional rigs or enter into lower day rate contracts or contracts with less favorable terms. There can be no assurance that the current demand for drilling rigs will not decline in future periods. In addition, the combined company’s or its competitors’ rigs that are “stacked” (i.e., minimally crewed with little or no scheduled maintenance being performed) may re-enter the market. The entry into service of newly constructed, upgraded or reactivated units will increase marketed supply and could reduce, or curtail a strengthening of, dayrates in the affected markets as rigs are absorbed into the active fleet. A decline in demand for drilling rigs or an increase in drilling rig supply could adversely affect the financial position, operating results and cash flows of the combined company.

Deterioration of the global economy and/or a decline in oil and natural gas prices could cause the customers of the combined company to reduce spending on exploration and development drilling. These conditions could also cause the customers and/or vendors of the combined company to fail to fulfill their commitments and/or fund future operations and obligations, which could have a material adverse effect on the business of the combined company.

The success of the business of the combined company largely depends on the level of activity in offshore oil and natural gas exploration and development drilling worldwide. Oil and natural gas prices, and market expectations of potential changes in these prices, significantly impact the level of worldwide drilling activity.

A decline in oil and natural gas prices, whether caused by economic conditions, international or national climate change regulations or other factors, could cause oil and gas companies to reduce their overall level of drilling activity and spending. Disruption in the capital markets could also cause oil and gas companies to reduce their overall level of drilling activity and spending.

Historically, when drilling activity and spending decline, utilization and day rates also decline and drilling activity may be reduced or discontinued, resulting in an oversupply of drilling rigs. The oversupply of drilling rigs could be exacerbated by the entry of newbuild rigs into the market. When idled or stacked, drilling rigs do not earn revenues, but continue to require cash expenditures for crews, fuel, insurance, berthing and associated items.

A decline in oil and natural gas prices, together with a deterioration of the global economy, could substantially reduce demand for drilling rigs and adversely affect the financial position, operating results and cash flows of the combined company.

Ensco has incurred substantial additional indebtedness to finance the merger and Pride’s existing indebtedness will remain outstanding upon completion of the merger, which will decrease the combined company’s business flexibility and increase its borrowing costs.

Upon completion of the merger, the level of consolidated indebtedness of the combined company will increase by the amount of the debt financing incurred to fund the cash component of the merger consideration and by approximately $1.86 billion of Pride’s debt that will remain outstanding after the merger. See “Description of Debt Financing.” The combined company’s increased indebtedness and higher debt-to-equity ratio in comparison to that of Ensco on a recent historical basis may have the effect, among other matters, of reducing the combined company’s flexibility to respond to changing business and economic conditions, lowering credit ratings, reducing access to capital and increasing borrowing costs for any additional indebtedness to finance future operating and capital expenses and for general corporate purposes. In addition, the terms and conditions of such indebtedness may not be favorable to the combined company, and, as such, could further increase the overall burden of such indebtedness upon the combined company and the combined company’s business flexibility. Unfavorable debt financing terms may also adversely affect the combined company’s financial results.

Many of the anticipated benefits of combining Ensco and Pride may not be realized.

Ensco and Pride entered into the merger agreement with the expectation that the merger would result in various benefits including, among others, synergies, cost savings, accretion to earnings per share in 2011, maintaining business and customer levels of activity and operating efficiencies. The success of the merger will depend, in part, on the combined company’s ability to realize these anticipated benefits from combining the businesses of Ensco and Pride. However, to realize these anticipated benefits, the combined company must successfully integrate the businesses of Ensco and Pride. If we are not able to achieve these objectives, the anticipated benefits of the merger may not be realized fully or at all or may take longer to realize than expected.

Ensco and Pride have operated and, until the completion of the merger, will continue to operate independently. It is possible that the integration process could take longer than anticipated and could result in the loss of valuable employees or the disruption of each company’s ongoing businesses or inconsistencies in standards, controls, procedures, practices, policies and compensation arrangements, which could adversely affect the combined company’s ability to achieve the anticipated benefits of the merger. The combined company’s results of operations could also be adversely affected by any issues attributable to either company’s operations that arise or are based on events or actions that occur prior to the closing of the merger. Further, the size of the merger may make integration difficult, expensive and disruptive, adversely affecting Ensco’s revenues after the merger. Ensco may have difficulty addressing possible differences in corporate cultures and management philosophies.

Integration efforts, including the expected relocation of Ensco’s U.S. headquarters to Houston from Dallas, will also divert management attention and resources. These integration activities could have an adverse

effect on the businesses of both Ensco and Pride during the transition period. The integration process is subject to a number of uncertainties. Although Ensco’s plans for integration are focused on minimizing those uncertainties to help achieve the anticipated benefits, no assurance can be given that these benefits will be realized or, if realized, the timing of their realization. Failure to achieve these anticipated benefits could result in increased costs or decreases in the amount of expected revenues and could adversely affect Ensco’s future business, financial condition, operating results and prospects. In addition, Ensco and Pride may not be able to eliminate duplicative costs or realize other efficiencies from integrating the businesses to offset part or all of the transaction and merger-related costs incurred by Ensco and Pride.

Business issues currently faced by one company may be imputed to the operations of the other company.

To the extent that either Ensco or Pride currently has or is perceived by customers to have operational challenges, such as timely or efficient performance, safety issues or workforce issues, those challenges may raise concerns by existing customers of the other company following the merger which may limit or impede Ensco’s future ability to obtain additional work from those customers.

Failure to recruit and retain employees and skilled personnel could adversely affect the operations and financial results of the combined company.

The combined company will need to recruit and retain employees and skilled personnel to operate the drilling rigs, manage the combined business and provide technical services and support for the combined business. Competition for skilled and other labor has intensified as additional rigs are added to the worldwide fleet. There are 62 new jackups, 21 semisubmersible rigs and 41 drillships, including those of Ensco and Pride, reported to be on order or under construction with delivery expected by the end of 2013. This represents an increase in the respective total worldwide fleets of 13% for jackups, 10% for semisubmersibles and 64% for drillships. These rigs will require new skilled and other personnel to operate. In periods of high utilization, it is more difficult and costly to recruit and retain qualified employees. Competition for such personnel could increase future operating expenses, with a resulting reduction in net income, or impact our ability to fully staff and operate the rigs.

Notwithstanding current global economic conditions, the combined company may be required to maintain or increase existing levels of compensation to retain a skilled workforce. Much of the skilled workforce is nearing retirement age, which may impact the availability of skilled personnel. The combined company may also be subject to potential further unionization of the labor force or legislative or regulatory action that may impact working conditions, paid time off or other conditions of employment. If such labor trends continue, they could further increase the costs or limit the ability of the combined company to fully staff and operate the rigs.

The operations of the combined company will require the successful integration of different business units and geographic areas of operation. The loss of supervising and management personnel could adversely affect the combined company’s ability to operate efficiently because of the experience and knowledge of such personnel. The loss of the services of employees and skilled personnel could adversely affect the combined company’s future operating results.

Contract revenues of the combined company after the merger could decrease if parties who are currently customers of both Ensco and Pride elect to reduce their reliance on the combined company after the merger.

Ensco and Pride currently have some customer overlap. If any of these common customers decrease their amount of business with the combined company following the merger to reduce their reliance on a single company or for other reasons, such decrease in business could adversely impact the sales and profitability of the combined company following the merger.

Failure to comply with the U.S. Foreign Corrupt Practices Act and terms of agreements with the U.S. Department of Justice, or the DOJ, and the SEC could result in fines, criminal penalties, contract terminations and an adverse effect on the combined company’s business.

The DOJ and SEC and other authorities have a broad range of civil and criminal sanctions under the U.S. Foreign Corrupt Practices Act, referred to as the FCPA, and other laws, which they may seek to impose in appropriate circumstances. Recent civil and criminal settlements with a number of public corporations, including Pride, and individuals have included multi-million dollar fines, disgorgement, injunctive relief, guilty pleas, deferred prosecution agreements and other sanctions, including requirements that corporations retain a monitor to oversee compliance with the FCPA.

During the course of an internal audit and investigation relating to certain of Pride’s Latin American operations, Pride’s management and internal audit department received allegations of improper payments to foreign government officials. In February 2006, the Audit Committee of Pride’s Board of Directors assumed direct responsibility over the investigation and retained independent outside counsel to investigate the allegations, as well as corresponding accounting entries and internal control issues, and to advise the Audit Committee. Pride voluntarily disclosed information relating to the initial allegations and other information found in the investigation and compliance review to the DOJ and the SEC, and cooperated with these authorities.

Pride has entered into settlements with the DOJ and the SEC regarding the FCPA matters. The settlement with the DOJ included a deferred prosecution agreement, or DPA, between Pride and the DOJ and a guilty plea by Pride’s French subsidiary, Pride Forasol S.A.S., to FCPA-related charges. Under the DPA, the DOJ agreed to defer the prosecution of certain FCPA-related charges against Pride and agreed not to bring any further criminal or civil charges against Pride or any of its subsidiaries related to either any of the conduct set forth in the statement of facts attached to the DPA or any other information Pride disclosed to the DOJ prior to the execution of the DPA. Pride agreed, among other matters, to continue to cooperate with the DOJ, to continue to review and maintain its anti-bribery compliance program and to submit to the DOJ three annual written reports regarding its progress and experience in maintaining and, as appropriate, enhancing its compliance policies and procedures. If Pride complies with the terms of the DPA, the deferred charges against Pride will be dismissed with prejudice. If, during the term of the DPA, the DOJ determines that Pride has committed a felony under federal law, provided deliberately false information or otherwise breached the DPA, Pride could be subject to prosecution and penalties for any criminal violation of which the DOJ has knowledge, including the deferred charges.

In December 2010, pursuant to a plea agreement, Pride Forasol S.A.S. pled guilty in U.S. District Court to conspiracy and FCPA charges. Pride Forasol was sentenced to pay a criminal fine of $32.6 million and to serve a three-year term of organizational probation. The SEC investigation was resolved in November 2010. Without admitting or denying the allegations in a civil complaint filed by the SEC, Pride consented to the entry of a final judgment ordering disgorgement plus pre-judgment interest totaling $23.6 million and a permanent injunction against future violations of the FCPA. Under the terms of the deferred prosecution agreement, as provided in the merger agreement, upon consummation of the merger, Ensco will assume the obligations of Pride under the deferred prosecution agreement, which will apply to Ensco and its subsidiaries following the merger. If there are any violations of the FCPA, the deferred prosecution agreement or the SEC injunction, any additional fines, sanctions or other penalties from other governmental authorities or any third party claims by other constituents of Pride in relation to these matters, it could significantly and adversely affect the results of operations of the combined company.

Further, Pride has received preliminary inquiries from governmental authorities of certain of the countries referenced in its settlements with the DOJ and the SEC. The combined company could face additional fines, sanctions and other penalties from authorities in these and other relevant foreign jurisdictions, including prohibition of its participating in or curtailment of business operations in those jurisdictions and the seizure of its rigs or other assets. At this early stage of such inquiries, neither Ensco nor Pride is able to determine what, if any, legal liability may result. Customers of the combined company in those jurisdictions could seek to impose penalties or take other actions adverse to the combined company’s interests. The combined company

could also face other third-party claims by directors, officers, employees, affiliates, advisors, attorneys, agents, stockholders, debt holders, or other interest holders or constituents of the combined company.

World political events, terrorist attacks, piracy and military action could affect the markets for the combined company’s services and have a material adverse effect on the combined company’s business and cost and availability of insurance.

World political events have resulted in military action in Afghanistan, Iraq and Libya; terrorist, pirate and other armed attacks globally; and civil unrest, political demonstrations, mass strikes and government responses in North Africa and the Middle East. Military action by the United States or other nations could escalate; further acts of terrorism, piracy, kidnapping, extortion and acts of war may occur; and violence, civil war and general disorder may continue in North Africa and the Middle East. Such acts of terrorism, piracy, kidnapping, extortion, violence, civil war, mass strikes and government responses could be directed against companies such as the combined company. Such developments have caused instability in the world’s financial and insurance markets in the past. In addition, these developments could lead to increased volatility in prices for crude oil and natural gas and could affect the markets for the combined company’s products and services. Insurance premiums could increase and coverages may be unavailable in the future. Any or all of these effects could have a material adverse effect on the combined company’s business.

The business of the combined company will be subject to operating hazards present in the offshore drilling industry, as well as adverse weather conditions, and the combined company may not have insurance to cover all these hazards.

The operations of Ensco and Pride are subject to hazards present in the offshore drilling industry, such as hurricanes, fire, explosion, blowouts, craterings, punchthroughs, oil spills and leaks or spills of hazardous materials. These incidents as well as accidents or problems in operations can cause personal injury or death and damage to property, reservoirs or the environment. The customer’s operations can also be interrupted. From time to time, customers seek recovery for damages caused by the activities of the offshore drilling contractors. Damage to the customer’s property or interests in oil or gas production formations could be extensive if a major problem occurred. In addition, U.S. operations could be materially affected by severe weather in the Gulf of Mexico. Severe weather, such as hurricanes, may cause evacuation of personnel and curtailment of services, damage to offshore drilling rigs resulting in suspension of operations, and loss of or damage to equipment, inventory, and facilities, which may not be insured in whole or in part. If material, damage from any such operating hazards or adverse weather conditions could adversely affect the results of operations of the combined company and the expected benefits of the merger. The combined company may not be able to maintain adequate insurance at rates or on terms that we consider reasonable or acceptable or be able to obtain insurance against certain risks.

The offshore drilling operations of the combined company could be adversely impacted by the Macondo well incident and the resulting changes in regulation of offshore oil and gas exploration and development activity.

In May 2010, the U.S. Department of the Interior implemented a six-month moratorium/suspension on certain drilling activities in water depths greater than 500 feet in the U.S. Gulf of Mexico. The U.S. Department of the Interior subsequently issued Notices to Lessees, or NTLs, implementing additional safety and certification requirements applicable to drilling activities in the U.S. Gulf of Mexico, imposed additional requirements with respect to development and production activities in the U.S. Gulf of Mexico and has delayed the approval of applications to drill in both deepwater and shallow-water areas. On July 12, 2010, the U.S. Department of the Interior issued a revised moratorium/suspension on drilling in the U.S. Gulf of Mexico, which was lifted on October 12, 2010 after the adoption on September 30, 2010 of new regulations relating to the design of wells and testing of the integrity of wellbores, the use of drilling fluids, the functionality and testing of well control equipment, including third-party inspections, minimum requirements for personnel, blowout preventers and other safety regulations.

As a condition to lifting of the moratorium/suspension, the Bureau of Ocean Energy Management, Regulation and Enforcement, or the BOEM, was directed to require that each operator demonstrate that it has written and enforceable commitments that ensure that containment resources are available promptly in the event of a blowout and that the chief executive officer of each operator certify to the BOEM that the operator has complied with applicable regulations. The BOEM intends to conduct inspections of each deepwater drilling operation for compliance with regulations, including but not limited to the testing of blowout preventers. It is unclear when these requirements will be satisfied, due in part to the limited staffing of the BOEM.

Certain of the drilling rigs of the combined company currently in the U.S. Gulf of Mexico have been or may be further affected by the regulatory developments and other actions that have or may be imposed by the U.S. Department of the Interior, including the regulations issued on September 30, 2010. The moratoriums/suspensions (which have been lifted), related NTLs, delays in processing drilling permits and other actions are being challenged in litigation by Ensco and others. Rig utilization and day rates of the combined company have been and may be further negatively influenced due to regulatory requirements and delays in customers’ ability to secure permits. Current or future NTLs or other directives and regulations may further impact customers’ ability to obtain permits and commence or continue deep or shallow water operations in the U.S. Gulf of Mexico.

Ensco has filed suit in the U.S. District Court for the Eastern District of Louisiana to seek relief from these actions which it believes violate the U.S. Administrative Procedure Act and the Outer Continental Shelf Lands Act. On February 17, 2011, the Court granted Ensco a preliminary injunction compelling the BOEM to process five pending drilling permit applications related to Ensco rigs within 30 days. The BOEM has issued a permit to one of Ensco’s customers since the Court’s ruling, which is the first permit issued by the BOEM to drill a deepwater well since the moratorium/suspension. Ensco is not able to predict whether or at what frequency the BOEM may issue further permits or the outcome of these legal proceedings, whether enforcement of any new actual or de facto moratorium/suspension and other related restrictions and delays will be enjoined, or whether the U.S. Department of the Interior will seek to implement additional restrictions on or prohibitions of drilling activities in the U.S. Gulf of Mexico.

Ensco has 12 rigs under contract in the U.S. Gulf of Mexico, including four ultra-deepwater semisubmersible rigs such as ENSCO 8503, which has been sublet to work in French Guiana. Ensco’s customers may seek to move other rigs to locations outside the U.S. Gulf of Mexico, perform activities permitted under the enhanced safety requirements, assign or suspend the contracts or attempt to terminate contracts pursuant to their respective force majeure or other provisions. In 2010, Pride took delivery of two of its new ultra-deepwater drillships under construction, the Deep Ocean Ascension and the Deep Ocean Clarion. The rigs were originally intended for drilling operations in the U.S. Gulf of Mexico. However, due to the moratorium on drilling in the U.S. Gulf of Mexico and more recently due to regulatory changes that have created delays and uncertainty regarding the resumption of drilling in the U.S. Gulf of Mexico, BP Exploration & Production Inc., or BP E&P, agreed to place the Deep Ocean Ascension and Deep Ocean Clarion on special standby day rates. The rigs are expected to mobilize to regions outside of the U.S. Gulf of Mexico by mid-2011. For a discussion of the drillships and related matters, see “Management’s Discussion and Analysis of Financial Condition and Results of Operations — Recent Developments — Recently Delivered Drillships” and “— U.S. Gulf of Mexico” in Pride’s Annual Report on Form 10-K for the year ended December 31, 2010.

At this time, neither Ensco nor Pride can predict the impact of the Macondo well incident and resulting changes in the regulation of offshore oil and gas exploration and development activity on their operations or contracts, the extent to which drilling operations subsequent to the moratorium period will be affected, the extent to which the issuance of permits for new or continued drilling will be delayed, the effect on the cost or availability of relevant insurance coverage, the effect on the demand for services in or outside the U.S. Gulf of Mexico or what actions may be taken by customers, other industry participants or the U.S. or other governments in response to the incident. Future legislative or regulatory enactments may impose new requirements for well control and blowout prevention equipment that could increase costs and cause delays in the operations of the combined company due to unavailability of associated equipment.

Prolonged actual or de facto delays, moratoria or suspensions of drilling activity in the U.S. Gulf of Mexico and associated new regulatory, legislative or permitting requirements in the U.S. or elsewhere could materially adversely affect the financial condition, operating results or cash flows of the combined company.

Compliance with or breach of environmental laws can be costly and could limit the operations of the combined company.

The operations of the combined company will be subject to laws and regulations controlling the discharge of materials into the environment, pollution, contamination and hazardous waste disposal or otherwise relating to the protection of the environment. Environmental laws and regulations specifically applicable to the business activities of the combined company could impose significant liability for damages, clean-up costs, economic loss, fines and penalties in the event of oil spills or similar discharges of pollutants or contaminants into the environment or improper disposal of hazardous waste generated in the course of operations. To date, such laws and regulations have not had a material adverse effect on the operating results of either Ensco or Pride, and neither Ensco nor Pride has experienced an accident that has exposed it to material liability for discharges of pollutants into the environment. However, the legislative and regulatory response to the Macondo well incident could substantially increase liabilities of oil and gas companies in respect of oil spills and also could increase the liabilities of the combined company. In addition to potential increased liabilities, such legislative or regulatory action could impose increased financial, insurance or other requirements that may adversely impact the entire offshore drilling industry.

The International Convention on Oil Pollution Preparedness, Response and Cooperation, the U.K. Merchant Shipping Act 1995, the U.K. Merchant Shipping (Oil Pollution Preparedness, Response and Cooperation Convention) Regulations 1998 and other related legislation and regulations and the U.S. Oil Pollution Act of 1990, or OPA 90, and other U.S. federal statutes applicable to the operations of the combined company, as well as similar statutes in Texas, Louisiana, other coastal states and other non-U.S. jurisdictions, address oil spill prevention and control and significantly expand liability, fine and penalty exposure across many segments of the oil and gas industry. Such statutes and related regulations impose a variety of obligations related to the prevention of oil spills, disposal of waste and liability for resulting damages. For instance, OPA 90 imposes strict and, with limited exceptions, joint and several liability upon each responsible party for oil removal costs as well as a variety of fines, penalties and damages. Failure to comply with these statutes and regulations, including OPA 90, may subject the combined company to civil or criminal enforcement action, which may not be covered by contractual indemnification or insurance and could have a material adverse effect on the financial position, operating results and cash flows of the combined company.

Events in recent years, including the Macondo well incident, have heightened governmental and environmental concerns about the oil and gas industry. From time to time, legislative proposals have been introduced that would materially limit or prohibit offshore drilling in certain areas. Ensco and Pride are adversely affected by restrictions on drilling in certain areas of the U.S. Gulf of Mexico and elsewhere, including the conditions for lifting the recent moratorium/suspension in the U.S. Gulf of Mexico, the adoption of associated new safety requirements and policies regarding the approval of drilling permits, restrictions on development and production activities in the U.S. Gulf of Mexico and associated NTLs that have and may further impact the operations of the combined company. If new laws are enacted or other government action is taken that restrict or prohibit offshore drilling in principal areas of operation or impose environmental protection requirements that materially increase the liabilities, financial requirements, oil spill response capabilities or operating or equipment costs associated with offshore drilling, exploration, development or production of oil and natural gas, the financial position, operating results and cash flows of the combined company could be materially adversely affected.

Drilling contracts with national oil companies will expose the combined company to greater risks than normally assumed.

Ensco currently has 12 rigs contracted with national oil companies. Pride also has 10 rigs contracted with national oil companies. The terms of these contracts are often non-negotiable and may expose us to greater commercial, political and operational risks than we assume in other contracts such as exposure to greater

environmental liability, the risk that the contract may be terminated by our customer without cause on short-term notice, contractually or by governmental action, under certain conditions that may not provide us an early termination payment, collection risks and political risks. Neither Ensco nor Pride can provide any assurance that the increased risk exposure will not have an adverse impact on future operations or that either will not increase the number of rigs contracted to national oil companies with commensurate additional contractual risks.

Laws and governmental regulations may add to costs, limit drilling activity or reduce demand for the drilling services of the combined company.

The operations of the combined company may be affected by political developments and by laws and regulations that relate directly to the oil and gas industry, including initiatives to limit greenhouse gas emissions. The offshore contract drilling industry is dependent on demand for services from the oil and gas industry. Accordingly, the combined company will be directly affected by the approval and adoption of laws and regulations limiting or curtailing exploration and development drilling for oil and natural gas for economic, environmental, safety and other policy reasons. The combined company may be exposed to risks related to new laws or regulations pertaining to climate change, carbon emissions or energy use that could reduce the use of oil or natural gas, thus reducing demand for hydrocarbon-based fuel and drilling services. Governments also may pass laws or regulations encouraging or mandating the use of alternative energy sources, such as wind power and solar energy, which may reduce demand for oil and natural gas and our drilling services. Furthermore, the combined company may be required to make significant capital expenditures or incur substantial additional costs to comply with new governmental laws and regulations. It is also possible that legislative and regulatory activity could adversely affect the operations of the combined company by limiting drilling opportunities, reducing consumption of hydrocarbon fuels or significantly increasing the operating costs of the combined company.

Risk Factors Relating to Ensco’s Redomestication to the U.K.

Ensco has not requested a ruling from Her Majesty’s Revenue and Customs, or HMRC, on the U.K. tax aspects of the redomestication, and HMRC may disagree with its conclusions.

Based on current U.K. corporation tax law and the current U.K.-U.S. income tax treaty, as amended, Ensco expects that its redomestication in 2009 will not result in any material U.K. corporation tax liability to it. Further, Ensco believes that it has satisfied all stamp duty reserve tax, or SDRT, payment and filing obligations in connection with the issuance and deposit of its Class A ordinary shares into the ADS depositary.

However, if HMRC disagrees with this view, it may take the position that material U.K. corporation tax or SDRT liabilities or amounts on account thereof are payable by Ensco as a result of the redomestication, in which case Ensco expects that it would contest such assessment. If Ensco were unsuccessful in disputing the assessment, the implications could be materially adverse to Ensco and the combined company. Ensco has not requested an HMRC ruling on the U.K. tax aspects of the redomestication, and there can be no assurance that HMRC will agree with its interpretations of U.K. corporation tax law or any related matters associated therewith.

The IRS may disagree with Ensco’s conclusions on tax treatment of certain restructuring transactions following the redomestication.

Ensco expects that the redomestication will not result in any material U.S. federal income tax liability to it, and the IRS has confirmed to Ensco that it will not challenge Ensco’s conclusion that the redomestication resulted in Ensco becoming tax resident in the U.K. However, the IRS may disagree with Ensco’s assessments of the effects or interpretation of the tax laws, treaties or regulations or their enforcement with respect to certain restructuring transactions that it completed after the redomestication. In this event Ensco may not realize the expected tax benefits of the redomestication, and the operating results of the combined company may be adversely affected in comparison to what they would have been if the IRS agreed with Ensco’s conclusions.

If Ensco and its non-U.S. subsidiaries become subject to U.S. federal income tax, its financial position, operating results and cash flows would be adversely affected.

Ensco and its non-U.S. subsidiaries will conduct their operations in a manner intended to minimize the risk that Ensco or its non-U.S. subsidiaries engage in the conduct of a U.S. trade or business. Its U.S. subsidiaries will continue to be subject to U.S. federal income tax on their worldwide income, and its non-U.S. subsidiaries will continue to be subject to U.S. federal income tax on their U.S. operations. However, if Ensco or any of its non-U.S. subsidiaries is or are determined to be engaged in a trade or business in the U.S., Ensco or such non-U.S. subsidiaries would be required to pay U.S. federal income tax on income that is subject to the taxing jurisdiction of the U.S. If this occurs, the financial position, operating results and cash flows of the combined company may be adversely affected.

The redomestication may not allow Ensco to maintain a competitive consolidated effective income tax rate.

Ensco believes the redomestication should improve its ability to maintain a competitive consolidated effective income tax rate because the U.K. corporate tax rate is lower than the U.S. corporate tax rate and because the U.K. has implemented a dividend exemption system that generally does not subject non-U.K. earnings to U.K. tax when such earnings are repatriated to the U.K. in the form of dividends from non-U.K. subsidiaries. In 2010, the new U.K. Government announced its intention that there will be a phased reduction in the headline rate of U.K. corporation tax from 27% to 24% by 2014, its lowest ever rate.

The U.K. has implemented controlled foreign companies rules, referred to as the CFC rules, under which, in certain circumstances, the income or profits of controlled non-U.K. resident companies which are subject to a lower level of taxation may be subject to U.K. corporation tax, subject to credit relief for foreign tax on those profits. The HMRC has granted Ensco an exemption from the CFC rules in respect of its material non-U.K. operations under the “motive test” exemption until December 31, 2012, subject to certain conditions and limitations based on its facts and circumstances.

In June 2010, the new U.K. Government announced in its Emergency Budget that it aims to create the most competitive corporate tax system in the G20, and that as a first step it will reform the U.K.’s CFC rules, which it recognized as a key priority for U.K. multinationals. The U.K. Government’s policy is that the U.K.’s corporate tax system should focus more on profits from U.K. activity in determining the tax base, rather than attributing the worldwide income of a group to the U.K. It has been announced that legislation for new CFC rules will be introduced in the spring of 2012, allowing time to consider how to make the rules more competitive, to enhance long-term stability and to provide adequate protection of the U.K. tax base. The U.K. Government launched a consultation on the reform of the CFC rules in November 2010 which will continue until late February 2011, and it intends to publish draft legislation in respect of the same during the second half of 2011. At the same time, the U.K. Government also launched a consultation on certain interim improvements to the current CFC rules, to make the rules easier to operate and, where possible, increase competitiveness. The U.K. Government published draft legislation in respect of the same on December 9, 2010. Legislation on interim improvements to the CFC rules will be introduced during the first half of 2011. The effect of any changes to the CFC rules on Ensco’s effective rate of income taxation will not be clear until the new legislation is published and enacted in its entirety. However, it is anticipated that these reforms will generally be favorable to the combined company, as compared to the current CFC rules. Nevertheless, as the U.K.’s current CFC rules for the most part do not apply to Ensco’s material overseas operations until December 31, 2012, its ability to efficiently manage those operations with a view to managing its effective income tax rates may be restricted by virtue of the new CFC rules from January 1, 2013. In the event that the U.K. Government adopts changes to the CFC rules that have the effect of increasing the consolidated effective income tax rate, the results of operations of the combined company may be adversely affected unless it is able to identify and implement any mitigating actions.

Ensco cannot provide any assurances as to what its effective income tax rates will be because of, among other reasons, uncertainty regarding the nature and extent of its business activities in any particular jurisdiction in the future and the tax laws of such jurisdictions, as well as potential changes in U.K. and U.S. tax laws.

Ensco’s actual effective income tax rates may vary from expectations and those variances may be material. Additionally, the tax laws of other jurisdictions could change in the future, and such changes could cause a material change in the consolidated effective income tax rate.

Ensco also could be subject to future audits conducted by U.K., U.S. and other tax authorities, and the resolution of such audits could significantly impact its effective income tax rates in future periods, as would any reclassification or other matter (such as changes in applicable accounting rules) that increases the amounts it has provided for income taxes in its consolidated financial statements. There can be no assurance that Ensco would be successful in attempting to mitigate the adverse impacts resulting from any changes in law, audits and other matters. The inability to mitigate the negative consequences of any changes in the law, audits and other matters could cause the effective income tax rates to increase and the financial position, operating results or cash flows of the combined company to be adversely affected.

Changes in laws, including tax law changes, could adversely affect Ensco, its subsidiaries and its securityholders.

Changes in tax laws, regulations or treaties or the interpretation or enforcement thereof, in the U.S., the U.K. or elsewhere, could adversely affect the tax consequences of the redomestication and post-redomestication internal restructuring to Ensco and its shareholders and/or its effective income tax rates (whether associated with the redomestication, the subsequent internal restructuring or otherwise). For example, one reason for the redomestication was to begin to align its structure so as to have an opportunity to take advantage of U.K. corporate tax rates, which are lower than the U.S. income tax rates, and to take advantage of the recent dividend exemption system implemented in the U.K., which generally does not subject earnings of non-U.K. subsidiaries to U.K. tax when such earnings are repatriated to the U.K. as dividends. Future changes in tax laws, regulations or treaties or the interpretation or enforcement thereof in general or any such changes resulting in a material change in the U.S. or U.K. tax rates in particular could reduce or eliminate the benefits that Ensco expects to achieve from the redomestication.

Changes in effective income tax rates or adverse outcomes resulting from examination of Ensco’s tax returns could adversely affect its financial results.

Changes in the valuation of Ensco’s deferred tax assets and liabilities or changes in tax treaties, regulations, accounting principles or interpretations thereof in one or more countries in which it operates could result in a higher effective income tax rate on worldwide earnings and such change could be significant to financial results. Ensco’s future effective income tax rates could also be adversely affected by lower than anticipated earnings in countries where it has lower statutory rates and higher than anticipated earnings in countries where it has higher statutory rates. In addition, Ensco is subject to examinations of its income tax returns by HMRC, the IRS and other tax authorities. Ensco regularly assesses the likelihood of adverse outcomes resulting from these examinations to determine the adequacy of the provision for income taxes. There can be no assurance that such examinations will not have an adverse effect on the financial position, operating results or cash flows of the combined company.

The expected financial, logistical and operational benefits of the redomestication may not be realized.

There can be no assurances that all of the goals of the redomestication will be achieved, particularly as achievement of Ensco’s goals is in many important respects subject to factors that it does not control. These factors include the reactions of U.K. and U.S. tax authorities, the reactions of third parties with whom it enters into contracts and conducts business and the reactions of investors and analysts.

While Ensco expects that the redomestication will enable it to take advantage of lower U.K. tax rates and the benefits of the U.K. dividend exemption system for certain non-U.K. source dividends repatriated to the U.K. in the years after implementation of the redomestication to a greater extent than would likely have been available if the redomestication had not occurred, these benefits may not be achieved. In particular, U.K. or U.S. tax authorities may challenge its application and/or interpretation of relevant tax laws, regulations or treaties, valuations and methodologies or other supporting documentation. If they are successful in doing so,

Ensco may not experience the level of benefits it anticipates, or it may be subject to adverse tax consequences. Even if Ensco is successful in maintaining its tax positions, Ensco may incur significant expenses in defending its position and contesting claims or positions asserted by tax authorities.

Whether Ensco realizes other expected financial benefits of the redomestication will depend on a variety of factors, many of which are beyond its control. These factors include changes in the relative rate of economic growth in the U.K. compared to the U.S., financial performance in jurisdictions with lower tax rates, foreign currency exchange rate fluctuations (especially as between the British pound and the U.S. dollar), and significant changes in trade, monetary or fiscal policies of the U.K. or the U.S., including changes in interest rates. It is difficult to predict or quantify the effect of these factors, individually and in the aggregate, in part because the occurrence of any of these events or circumstances may be interrelated. If any of these events or circumstances occur, Ensco may not be able to realize the expected financial benefits of the redomestication, and its expenses may increase to a greater extent than if it had not completed the redomestication.

Realization of the logistical and operational benefits of the redomestication is also dependent on a variety of factors including the geographic regions in which its rigs are deployed, the location of the business unit offices that oversee its global offshore contract drilling operations, the locations of its customer’s corporate offices and principal areas of operation and the location of investors. If events or changes in circumstances occur affecting the aforementioned factors, Ensco may not be able to realize the expected logistical and operational benefits of the redomestication, which could adversely affect the combined company.

Ensco has less flexibility as a U.K. public limited company with respect to certain aspects of capital management than U.S. corporations due to increased shareholder approval requirements.

Directors of a Delaware and other U.S. corporation may issue, without further shareholder approval, shares of common stock authorized in its certificate of incorporation that were not already issued or reserved. The business corporation laws of Delaware and other U.S. states also provide substantial flexibility in establishing the terms of preferred stock. However, English law provides that a board of directors may only allot shares with the prior authorization of shareholders, such authorization being up to the aggregate nominal amount of shares and for a maximum period of five years, each as specified in the articles of association or relevant shareholder resolution. Such authorization would need to be renewed by Ensco’s shareholders upon its expiration (i.e., at least every five years). A special resolution was adopted prior to the effective time of the redomestication in December 2009 to authorize the allotment of additional shares for a five-year term and renewal of such authorization for additional five-year terms may be sought more frequently.

English law also generally provides shareholders preemptive rights when new shares are issued for cash. However, it is possible for the articles of association or shareholders in a general meeting to exclude preemptive rights. Such an exclusion of preemptive rights may be for a maximum period of up to five years from the date of adoption of the articles of association, if the exclusion is contained in the articles of association, or from the date of the shareholder resolution, if the exclusion is by shareholder resolution. In either case, this exclusion would need to be renewed upon its expiration (i.e., at least every five years). A special resolution was adopted to exclude preemptive rights prior to the effective time of the redomestication in December 2009 for a five-year term and renewal of such exclusion for additional five-year terms may be sought more frequently.

English law prohibits Ensco from conducting “on-market purchases” as Ensco ADSs are not traded on a recognized investment exchange in the U.K. English law also generally prohibits a company from repurchasing its own shares by way of “off-market purchases” without the prior approval of 75% of its shareholders by special resolution. Such approval lasts for a maximum period of up to five years. Special resolutions were adopted prior to the effective time of the redomestication in December 2009 to permit “off-market purchases.” These special resolutions will need to be renewed upon expiration (i.e., at least every five years) to permit “off-market purchases” and renewal for additional five-year terms may be sought more frequently.

There can be no assurances that situations will not arise where such shareholder approval requirements for any of these actions would deprive the combined company’s shareholders of substantial benefits.

The redomestication will result in additional ongoing costs.

The redomestication has resulted in an increase in some of Ensco’s ongoing expenses and will require it to incur some new expenses. Some costs, including those related to relocation and employment of expatriate officers and other employees in Ensco’s U.K. offices and holding board of directors meetings in the U.K., are expected to be higher than would be the case if the principal executive offices remained in the U.S. Ensco has incurred and expects to continue to incur additional expenses, including professional fees, to comply with U.K. corporate and tax laws.

Risk Factors Relating to Ensco ADSs Following the Merger

The market value of Ensco ADSs could decline if large amounts of ADSs are sold following the merger.

Following the merger, shareholders of Ensco and former stockholders of Pride will own interests in a combined company operating an expanded business with more assets and a different mix of liabilities. Current shareholders of Ensco and stockholders of Pride may not wish to continue to invest in the additional operations of the combined company, or for other reasons, such as an inability to hold ADSs under the investment guidelines of various institutional investors, may wish to dispose of some or all of their interests in the combined company. If, following the merger, large amounts of Ensco ADSs are sold, the price of its ADSs could decline.

CAUTIONARY STATEMENT CONCERNING FORWARD-LOOKING STATEMENTS

This joint proxy statement/prospectus, including information included or incorporated by reference in this joint proxy statement/prospectus, may contain certain forward-looking statements within the safe harbor provisions of the Private Securities Litigation Reform Act of 1995. Forward-looking statements include words or phrases such as “anticipate,” “believe,” “contemplate,” “estimate,” “expect,” “intend,” “plan,” “project,” “could,” “may,” “might,” “should,” “will” and words and phrases of similar import. Without limiting the generality of the preceding sentence, certain statements contained in the sections “The Merger — Background of the Merger,” “The Merger — Recommendation of the Ensco Board of Directors and Its Reasons for the Merger” and “The Merger — Recommendation of the Pride Board of Directors and Its Reasons for the Merger” constitute forward-looking statements.

These forward-looking statements appear in a number of places and include statements with respect to, among others:


	•	projected operating or financial results, including any accretion/dilution to earnings and cash flow;

	•	the ability to integrate the operations of Ensco and Pride as contemplated;

	•	the amount and timing of any cost savings, synergies or operational or administrative efficiencies expected to result from the merger;

	•	the ability of each of Pride and Ensco to satisfy the conditions to closing of the merger;

	•	Ensco’s plans to obtain additional financing after the transaction;

	•	prospects for our services and expected activity in our areas of operations;

	•	the effects of competition in our areas of operations;

	•	the outlook of oil and gas prices;

	•	the current economic conditions and expected trends in the industry we serve;

	•	the amount, nature and timing of capital expenditures, including future development costs, and availability of capital resources to fund the merger and subsequent capital expenditures;


	•	the various risks and other factors considered by the respective boards of Ensco and Pride as described under “The Merger — Recommendation of the Ensco Board of Directors and Its Reasons for the Merger” and under “The Merger — Recommendation of the Pride Board of Directors and Its Reasons for the Merger”;

	•	the impact of political and regulatory developments in general and in the U.S. Gulf of Mexico in particular;

	•	future and pro forma financial condition or results of operations and future revenues and expenses; and

	•	business strategy and other plans and objectives for future operations.

Factors that could cause actual results to differ materially from those contemplated by the forward-looking statements include, among others, the following factors:


	•	the ability to consummate the merger, including the ability to resolve pending litigation seeking to prevent the merger;

	•	conditions in the credit markets for additional borrowing capacity after the merger;

	•	failure, difficulties and delays in obtaining regulatory clearances and approvals for the merger;

	•	failure, difficulties and delays in achieving expected synergies and cost savings;

	•	failure, difficulties and delays in meeting conditions required for closing set forth in the merger agreement;

	•	general economic and business conditions;

	•	prices of crude oil and natural gas and industry expectations about future prices;

	•	ability to adequately staff rigs;

	•	political stability in the countries in which the combined company will operate;

	•	the business opportunities (or lack thereof) that may be presented to and pursued by the combined company;

	•	cancellation or renegotiation of drilling contracts or payment or other delays, including acceptance testing delays, permit delays or defaults by customers;

	•	unplanned downtime and repairs on rigs, particularly due to the age of some of the rigs; and

	•	changes in laws and regulations.

Other factors that could cause actual results to differ materially from those contemplated by the forward-looking statements include, among others, the factors detailed in “Risk Factors” of this joint proxy statement/prospectus and the risk factors described in each company’s Annual Report on Form 10-K for the year ended December 31, 2010, which are filed with the SEC and available on the SEC’s website at www.sec.gov. Should one or more of the factors, risks or uncertainties described above materialize (or the other consequences of such a development worsen), or should underlying assumptions prove incorrect, actual results and plans could differ materially from those expressed in any forward-looking statements. You are cautioned not to place undue reliance on these statements, which speak only as of the date of this joint proxy/prospectus or the date of any document incorporated by reference in this joint proxy/prospectus, as applicable.

Any projection or estimate by Pride or Ensco that was furnished to its financial advisor, the other party or the other party’s financial advisor, including those statements summarized herein, was made as of a date before the date of the merger agreement and spoke only as of the date furnished and has not been updated. These estimates and projections were only intended to be used by the recipient for analysis of the merger and are not intended to provide guidance as to future results and should not be relied upon for that purpose.

All forward-looking statements, expressed or implied, included in this joint proxy statement/prospectus are expressly qualified in their entirety by this cautionary statement. This cautionary statement should also be considered in connection with any subsequent written or oral forward-looking statements that Ensco, Pride or persons acting on their behalf may issue.

All information in this document is as of today. Except as otherwise required by applicable law, Ensco and Pride disclaim any duty to update any forward-looking statements, whether as a result of new information, future events or otherwise, all of which are expressly qualified by the statements in this section. See also “Where You Can Find More Information; Incorporation by Reference.”

THE MERGER

The following is a description of the material aspects of the merger. While Ensco and Pride believe that the following description covers the material terms of the merger, the description may not contain all of the information that is important to Ensco shareholders and Pride stockholders. For a more complete understanding of the merger, Ensco and Pride encourage Ensco shareholders and Pride stockholders to carefully read this entire joint proxy statement/prospectus, including the merger agreement attached to this joint proxy statement/prospectus as Annex A and incorporated herein by reference.

Each of the Ensco and Pride boards of directors has unanimously approved the merger agreement and the transactions contemplated by the merger agreement. In the merger, Merger Sub will merge with and into Pride with Pride surviving the merger as an indirect wholly owned subsidiary of Ensco. Pride stockholders will be entitled to receive the merger consideration described below under “The Merger Agreement — Merger Consideration.”

Background of the Merger

Ensco continually reviews strategic options to improve its asset base and business opportunities. As part of its review, Ensco considers possible rig fleet combinations, geographic diversity and customer base opportunities that may be available through potential business combinations with companies that share the same core values of dedication to safety, ethics, operational excellence, employee development, customer satisfaction and disciplined risk management. At the regularly scheduled meetings of the Ensco board of directors, Daniel W. Rabun, the chairman of the board of directors and chief executive officer of Ensco, and management periodically update the board on various business strategies for Ensco and potential business combination transactions. Three of the highest strategic priorities identified by the Ensco management team were to continue to expand its deepwater business, enter the drillship business and enter West Africa and Brazil as key markets for future growth opportunities.

As part of the ongoing evaluation of its business, the Pride board of directors and management continually evaluate Pride’s business strategy and prospects for growth and consider opportunities to improve Pride’s operations and financial performance in order to create value for Pride stockholders. As part of this evaluation, Pride has regularly considered acquisitions of other companies or their assets, acquisition or construction of additional rigs or other assets and, on occasion, business combination transactions with other industry participants. In recent years, Pride has focused on increasing its high-specification assets, with a particular focus on expansion of its deepwater fleet. Pride’s management team also meets regularly with institutional investors who have expressed their views on consolidation in the offshore drilling industry and on Pride’s possible role in that consolidation. Senior management of Pride has from time to time engaged in preliminary discussions with other industry participants regarding the possibility of business combination transactions, and has reported these discussions to the Pride board of directors.

In late July 2005, Louis A. Raspino, who was promoted to president and chief executive officer of Pride in June 2005, met with Tor Olav Trøim, the chief executive officer of Seatankers Management Co. Ltd. and a vice president and director of Seadrill Limited, and discussed, among other things, a proposal by Seatankers to acquire a significant equity interest in Pride and obtain board representation. Mr. Trøim also referred to discussions between Mr. Trøim and the former chief executive officer of Pride. Mr. Trøim sent Mr. Raspino a letter dated August 3, 2005 confirming the proposal.

On August 9, 2005, Pride retained Goldman Sachs to assist Pride in evaluating the proposal letter at the August 10, 2005 meeting of the Pride board of directors.

On August 10, 2005, the Pride board of directors met with management, representatives of Goldman Sachs and Pride’s outside counsel, Baker Botts L.L.P. and Wachtell, Lipton, Rosen & Katz, to discuss the Seatanker proposal. Given Pride’s access to capital and other available opportunities and the inherent conflicts of interest with having a competitor owning a significant equity interest in the company with board representation, the Pride board determined not to pursue the opportunity, which response was conveyed to Mr. Trøim by letter dated August 10, 2005.

In March 2007, Mr. Raspino and the chief operating officer of Pride at the time met with Mr. Trøim and an advisor of Seadrill. Mr. Trøim stated that he was having discussions with a number of industry participants regarding a business combination transaction and would like to explore the possibility of a transaction with Pride. Mr. Trøim expressed Seadrill’s general interest in acquiring Pride in an all-cash transaction with a reasonable premium to Pride’s stockholders. No other terms were discussed. Mr. Raspino stated that he would discuss the matter with members of the Pride board of directors. The following week, Mr. Raspino called Mr. Trøim to respond to the prior discussion. Mr. Raspino stated that the Pride board would be open to considering any transaction that would be compelling to its stockholders. No specific proposal was made by Seadrill.

During the spring of 2007, Pride had preliminary discussions with Company A, an industry participant, regarding a possible business combination transaction involving cash and stock of Company A as consideration. The Pride board of directors held various meetings during that period with management and Pride’s legal and financial advisors to discuss the potential transaction. No specific proposals were made by Company A.

Pride and Goldman Sachs entered into a letter agreement dated as of August 10, 2007 and effective March 27, 2007, pursuant to which Pride engaged Goldman Sachs to act as its financial advisor in connection with the potential acquisition of Pride or any other attempts to acquire all or a significant portion of the stock or assets of Pride.

On January 29, 2008, Mr. Raspino met with Mr. Trøim to discuss industry matters. During the discussion, Mr. Trøim expressed a general interest in a combination transaction involving Seadrill and Pride without providing specifics. Mr. Trøim stated that Seadrill would not be interested in a hostile transaction involving Pride. Mr. Raspino reiterated that the Pride board would be open to considering any transaction that would be compelling to its stockholders. Mr. Trøim informed Mr. Raspino that John Fredriksen, the chairman of Seadrill, had acquired an unspecified number of shares of Pride for investment.

On April 12, 2008, Mr. Raspino received correspondence from Messrs. Fredriksen and Trøim regarding Seadrill’s and its affiliates’ acquisition, through undisclosed forward purchase contracts and other acquisitions from undisclosed parties, of approximately 9.9% of Pride’s outstanding common stock. Seadrill also advised Pride that it had made a filing under the HSR Act to permit Seadrill to acquire Pride securities. Seadrill also requested that Pride not publicly disclose its acquisition of Pride securities or its HSR filing.

On April 14, 2008, in order to assist the Pride board of directors and management with its consideration of the matter, Mr. Raspino and Baker Botts sent letters to Messrs. Fredriksen and Trøim and to Seadrill’s U.S. counsel, respectively, requesting information about Seadrill’s intentions, plans and proposals with respect to Pride and its acquisition of the common stock; any agreements, arrangements or understandings it has with third parties regarding Pride securities; the terms of the forward purchase contracts; the reasons for its HSR filing; and the maximum ownership level specified in the filing. On April 15, 2008, the Pride board met with management and its financial and legal advisors to discuss the matter. No information was ever provided by Seadrill or its counsel pursuant to the requests made on April 14.

On April 21, 2008, the Pride board again met with management and its financial and legal advisors. At the meeting, the board took action under Pride’s stockholder rights plan to lower, solely with respect to Seadrill and its affiliates and associates, the threshold level of beneficial ownership of Pride’s common stock that would trigger the rights from 15% to 10%. The board took the action with respect to the rights plan because, among other things, Seadrill had not provided Pride any information about its intentions, and the board wanted to make sure that all stockholders were protected appropriately. Pride issued a press release the next morning announcing the board’s action and the reasons therefor, including information regarding Seadrill’s positions in Pride stock. Shortly after the board action and press release, Mr. Raspino received a call from the chief executive officer of Company A, and Brian C. Voegele, the senior vice president and chief financial officer of Pride, received a call from Jay W. Swent, the chief financial officer of Ensco, regarding the ongoing Seadrill matter and their potential interest in a possible transaction with Pride if Pride thought such a transaction desirable.

On April 30, 2008, Messrs. Raspino and Voegele had a telephonic conference with Messrs. Fredriksen and Trøim. Messrs. Fredriksen and Trøim discussed in very general terms whether Seadrill and Pride should combine and the recent action taken by Pride under its rights plan. Messrs. Fredriksen and Trøim reiterated that Seadrill had no intention of conducting a hostile transaction with respect to Pride. They also inquired about a possible meeting between the parties.

On May 8, 2008, Messrs. Raspino and Voegele met with Messrs. Kjell E. Jacobsen and Alf C. Thorkildsen, the chief executive officer and the chief operating officer, respectively, of Seadrill at the time, to discuss a possible business combination transaction. The Seadrill representatives stated that a transaction structure involving a “merger of equals,” similar to the 2007 transaction between Transocean Ltd. and GlobalSantaFe Corporation, was generally of interest to Seadrill. The participants also discussed the benefits of industry consolidation in general, as well as Seadrill’s views of the jackup and tender markets. The Seadrill representatives stated that they would come back to Pride with more specifics regarding a proposed transaction. On May 27, 2008, Mr. Trøim called Mr. Raspino and generally discussed a possible merger of equals transaction structure without providing specifics, as well as general industry conditions.

On June 20, 2008, Messrs. Raspino and Voegele met with Mr. Trøim. At the meeting, Mr. Trøim stated that Seadrill had a general interest in a potential acquisition of Pride and would prefer an all-cash transaction on a negotiated basis. No pricing terms were proposed by Seadrill. Mr. Trøim also stated that, if Pride were not willing to proceed on a negotiated basis, Seadrill had prepared a draft “bear hug” letter and was willing to undertake a proxy contest if needed. Mr. Trøim discussed Seadrill’s need to conduct limited tax due diligence on Pride in order to make a proposal and stated that it would be willing to sign a confidentiality agreement to obtain the information. Mr. Trøim inquired as to the level of the premium Pride’s board of directors would require. Mr. Raspino responded that the Pride board would be open to considering any transaction that would be compelling to its stockholders. Mr. Raspino stated that he would discuss the matter with Pride’s board and would respond in early July 2008. Pride’s board met with management and Pride’s financial and legal advisors on June 24, 2008 and July 3, 2008 to discuss the June 20 meeting, Seadrill’s request for information and Pride’s response. On July 3, 2008, Messrs. Fredriksen and Trøim sent a letter to Mr. Raspino with respect to the matters discussed on June 20, which indicated that Seadrill was working with the intention to make an all cash proposal but would consider other forms of consideration.

On June 30, 2008, Mr. Raspino met with the chief executive officer of Company B, an industry participant, at the request of that officer. The chief executive officer of Company B expressed a general interest in a business combination with Pride, but indicated that Company B did not want to get into a bidding war with Seadrill. No specific proposal was made by Company B. The Pride board discussed this meeting at its July 3 meeting. On September 8, 2008, the chief executive officer of Company B and Mr. Raspino spoke while at an industry conference, and the chief executive officer of Company B again expressed interest in a transaction to Mr. Raspino, but no specific proposal was discussed.

On July 8, 2008 and consistent with the discussions of June 20, Mr. Raspino requested a telephone call with Mr. Trøim to continue the discussion. Mr. Trøim did not respond. Seadrill filed an initial Schedule 13D under the Exchange Act with respect to Pride securities on July 21, 2008.

On July 22, 2008, Messrs. Raspino and Voegele spoke by phone with Mr. Trøim. Mr. Raspino indicated that Pride would be willing to provide tax due diligence as requested by Seadrill upon execution of a confidentiality agreement. Mr. Trøim stated that Seadrill would be willing to do so and would provide Pride a list of the tax due diligence requested. Mr. Raspino reiterated that the Pride board would be open to considering any transaction that would be compelling to its stockholders. At various times between July 28, 2008 and August 2, 2008, representatives of Seadrill and Pride corresponded regarding the tax due diligence requested by Seadrill, and Pride provided a draft confidentiality agreement. In the correspondence, Mr. Trøim stated that it was Seadrill’s intention to present an attractive all-cash proposal for the consideration of Pride’s board.

Mr. Trøim responded to the draft confidentiality agreement on August 27, 2008 and requested that Pride’s counsel discuss certain issues raised with Seadrill’s counsel. Members of Pride’s legal department called

Seadrill’s counsel on August 29, 2008 to discuss open points on the agreement. Counsel agreed to have further discussions at a later date.

On September 16, 2008, Mr. Trøim called Mr. Raspino. With respect to the confidentiality agreement, Mr. Raspino proposed a compromise proposal to resolve the open points, and Mr. Trøim indicated the proposal was likely acceptable, but that he needed to confer with Mr. Fredriksen. Mr. Trøim stated that Seadrill was exploring financing proposals for a proposed transaction at a premium to the then-current market price. Thereafter, no further discussions regarding the draft confidentiality agreement or such a proposed transaction occurred.

From the summer of 2008 to the end of the year, the market prices for equity securities of offshore drilling companies generally (including Pride) declined significantly, in response to the worldwide financial and credit crisis and economic recession.

On January 14, 2009, Messrs. Raspino and Voegele met with Messrs. Trøim and Thorkildsen, who had been appointed as the chief executive officer of Seadrill in June 2008. The participants discussed general industry matters and the two companies’ respective newbuild programs. Mr. Trøim also discussed Seadrill’s discussions with other industry participants regarding business combinations. Mr. Trøim stated that Seadrill was still interested in pursuing an all-cash transaction on a negotiated basis and suggested that Pride stockholders might be willing to support a $30 per share offer price. Mr. Raspino responded that the Pride board would be open to considering any transaction that would be compelling to its stockholders. Mr. Trøim stated that Seadrill was testing the market for financing of the transaction. No specific proposal was made by Seadrill.

On June 18, 2009, Messrs. Raspino and Voegele met with Messrs. Fredriksen and Trøim. They discussed general industry conditions. Messrs. Fredriksen and Trøim expressed Seadrill’s continued interest in a transaction with Pride. No specific proposal was made by Seadrill.

On August 24, 2009, Pride completed the spin-off of Seahawk Drilling, Inc., which held the assets and liabilities that were associated with Pride’s mat-supported jackup rig business. In the spin-off, Pride stockholders received 100% of the outstanding common stock of Seahawk by way of a pro rata stock dividend.

On September 29, 2009, Messrs. Raspino and Voegele met with Messrs. Trøim and Thorkildsen. Messrs. Trøim and Thorkildsen expressed Seadrill’s continued interest in a transaction with Pride. They indicated that Seadrill would not be interested in a hostile transaction. Messrs. Trøim and Thorkildsen stated that Seadrill had drafted a written proposal that outlined a framework of a possible transaction. No specific proposals were made by Seadrill, and the written proposal was never provided to Pride.

On October 5, 2009, Mr. Raspino met with the chief executive officer and chief operating officer of Company C, an industry participant, at their request. At the meeting, Company C expressed a general interest in acquiring Pride in an at-market transaction. No specific proposal was ever made by Company C.

At various times in the fall of 2009, Mr. Raspino met with the chief executive officer of Company B in order to generally discuss a possible business combination transaction between the companies. At one of the meetings, Mr. Voegele and the chief financial officer of Company B and Company B’s financial advisors attended. Company B proposed a stock-for-stock merger transaction with a cash distribution to shareholders of both companies, similar to the 2007 Transocean/GlobalSantaFe transaction. Although the proposal did not include a premium to Pride stockholders, Company B later indicated that some level of premium could be provided to the Pride stockholders. The chief executive officer of Company B confirmed its interest in pursuing such a transaction in a letter dated November 17, 2009.

The Pride board of directors held several meetings from September to November 2009 with management and Pride’s financial and legal advisors to discuss ongoing developments with respect to Seadrill, Company B and Company C.

Mr. Raspino responded to the November 17 letter from Company B by letter dated December 10, 2009. Mr. Raspino indicated that Pride’s board did not believe it was appropriate to pursue further discussions

regarding a business combination transaction at that time in light of Pride’s strategic business plan, which focused on higher specification assets.

On April 15, 2010, Mr. Raspino met with the chief executive officer of Company B. They discussed general industry matters. The chief executive officer of Company B reiterated Company B’s interest in a strategic transaction with Pride, but made no specific proposal.

On April 20, 2010, the rig drilling the Macondo well in the U.S. Gulf of Mexico experienced an explosion and fire that resulted in, among other consequences, the death of several of the workers on the rig and a massive oil spill in the Gulf. The U.S. government responded by implementing a moratorium on drilling activities with respect to new wells in water depths greater than 500 feet in the U.S. Gulf of Mexico and issuing various environmental, technological and safety regulations. The Macondo well incident and governmental responses have had, and continue to have, a significant, lasting impact on the offshore drilling industry worldwide.

On May 28, 2010, Mr. Raspino was in London on business unrelated to a possible transaction and contacted Mr. Rabun about having a business luncheon. At that luncheon, Messrs. Raspino and Rabun discussed general industry matters, including the recent events associated with the Macondo well and resulting oil spill. They further discussed the core values shared by the companies and the relative strengths of each company. They also discussed the merits of a company needing scale to compete effectively in the future offshore drilling industry, especially given the events related to the Macondo well incident. Mr. Rabun inquired whether Pride had considered a strategic combination to achieve critical mass. Mr. Raspino responded that Pride was assessing the implications of recent events in the U.S. Gulf of Mexico and that the Pride board had not made any determination whether a strategic combination was in the best interests of Pride and its stockholders. Mr. Rabun indicated that Ensco was interested in exploring a strategic combination with Pride. Mr. Rabun and Mr. Raspino continued their discussions of these topics on July 15, 2010 after attending an industry event in Washington, D.C. related to the Macondo well incident.

On August 2, 2010 at the Ensco regularly scheduled quarterly board meeting, Mr. Rabun advised the Ensco board of his conversations with Mr. Raspino. The Ensco management team made an oral presentation of the various strategic priorities for Ensco and the alternatives to achieve those priorities. During an executive session of the meeting, the Ensco board authorized Mr. Rabun to continue the conversations with Mr. Raspino to determine whether Pride would have an interest in considering a strategic combination. On August 3, 2010, at the reconvened Ensco board meeting, Ensco’s outside counsel, Helen Bradley of Baker & McKenzie LLP, provided a general briefing on the fiduciary duties of directors under English law and discussed the similarities and differences of Delaware law in this regard.

On August 6, 2010, Mr. Raspino met with the chief executive officer of Company B. The chief executive officer of Company B again expressed an interest in exploring a strategic combination with Pride, but made no specific proposal.

In early September 2010, representatives of Seadrill called representatives of Goldman Sachs to ask that certain general terms of a proposed transaction structure be conveyed to Pride. Price and form of consideration were not discussed, but the transaction proposal contemplated that the combined company would be domiciled outside of the U.S. and that Seadrill would not require control of the board of the combined company. Mr. Raspino discussed this call with Pride’s board of directors on September 13, 2010. Mr. Raspino also updated the board on his discussions with Ensco and Company B.

On September 14, 2010, Mr. Rabun met with Mr. Raspino and continued their discussions. Mr. Raspino informed Mr. Rabun that the Pride board was preparing for its regularly scheduled board meeting in October 2010 to consider the company’s long-term strategic plan.

On September 29, 2010, Messrs. Raspino and Voegele met with Messrs. Fredriksen and Trøim and discussed, among other matters, a possible transaction between the companies. Mr. Trøim described a restructuring of the combined company into three separate companies, one holding premium assets, a second holding lower specification rigs and a third holding rigs working in Brazil. Mr. Trøim stated that Seadrill would be willing to pay a premium to Pride’s stockholders, similar to what he characterized as an 18% premium paid by Pride in its 2001 acquisition of Marine Drilling Companies, Inc. Mr. Trøim stated that the

transaction could be an all-stock transaction or include up to 40% cash. He stated that Seadrill was open-minded regarding the number of board seats Pride directors would have in the combined company, but stated that Seadrill would not require a majority of the board. However, Mr. Trøim stated that Seadrill would require that the combined company continue Seadrill’s financial strategy of significant financial leverage and significant cash dividends following a business combination. Mr. Trøim stated that Seadrill was only interested in a negotiated transaction and would be willing to make a written proposal to the Pride board if the board would consider a letter from Seadrill. Mr. Raspino responded that the Pride board was always open to considering any transaction that would be compelling to its stockholders. Later that day, the chief executive officer of Company B e-mailed Mr. Raspino about market rumors regarding a meeting by Mr. Raspino with competitors and requesting that Pride not enter into a transaction without discussing the matter with Company B.

On October 5, 2010, the Pride board of directors met with management and its financial and legal advisors to discuss the meeting with Seadrill and Seadrill’s willingness to submit a written proposal to the board. The board authorized management to meet with Seadrill to explore the possibility of a combination with Seadrill in more detail and to obtain more information about the matters discussed at the September 29 meeting. Based on various comments and inquiries from the media, other industry participants and stockholders following meetings or other contacts with Seadrill, the board also expressed concern about recurring public rumors regarding Seadrill’s actions and intentions with respect to Pride and requested management to discuss the matter with Seadrill.

On October 7, 2010, Mr. Raspino met with the chief executive officer of Company A. The chief executive officer of Company A suggested that the companies explore a possible strategic combination. No terms were discussed.

On October 14, 2010, Messrs. Raspino and Voegele met with Mr. Trøim and Esa Ikäheimonen, the chief financial officer of Seadrill, to explore the possibility of a combination with Seadrill and to obtain more information about the matters discussed at the September 29 meeting in order to assist Pride management prepare for the regularly scheduled board meeting later in October. Messrs. Trøim and Ikäheimonen discussed Seadrill’s operating and financial strategy, as well as their views on the offshore drilling industry after the Macondo well incident. They also discussed their views of the strategy of the combined company in Brazil. Mr. Trøim reiterated that Seadrill wanted to pursue only a negotiated transaction and that he would be willing to meet with Pride’s board if that would facilitate such a transaction. Mr. Trøim also indicated that Seadrill would pursue a transaction with another industry participant if Pride was not interested in a transaction with Seadrill. Mr. Raspino stated that the Pride board would be open to considering any transaction that would be compelling to its stockholders.

At its regularly scheduled meeting on October 18 and 19, 2010, the Pride board met with management and its legal and financial advisors. At the meeting, the ongoing discussions with Seadrill, Ensco, Company A and Company B were reviewed. Baker Botts and Wachtell Lipton discussed with the directors their fiduciary duties. Management reviewed with the board potential transactions involving certain companies in the industry. Representatives of Goldman Sachs then reviewed its preliminary financial analyses of the potential transactions.

On October 27, 2010, Messrs. Raspino and Voegele had a telephone conference with Mr. Trøim and discussed the companies’ interest in continuing to explore a possible combination transaction. Mr. Raspino stated that, following discussions at the October 18 and 19 board meetings, the Pride board was open to continuing discussions with Seadrill regarding a transaction, and would expect the parties to enter into an appropriate confidentiality agreement. Mr. Trøim indicated that Seadrill would need to retain its rights to pursue a hostile transaction.

Also on October 27, 2010, Mr. Rabun had a telephone conference with Mr. Raspino. Mr. Rabun informed Mr. Raspino that the Ensco board of directors was having its regularly scheduled quarterly board meeting on November 1, 2010 and inquired whether the Pride board of directors had an interest in considering a strategic combination with Ensco so the matter could be discussed, in general, at that board meeting. Mr. Raspino responded that the Pride board would be open to considering any transaction that would be compelling to its

stockholders. Mr. Raspino informed Mr. Rabun that Mr. Raspino would need to further discuss Ensco’s fleet and the market with the Pride board and requested Mr. Rabun to provide information in this regard.

On November 1 and 2, 2010, the Ensco board of directors held a regular quarterly board meeting in London attended by all members of the board, as well as members of management and representatives of Deutsche Bank. On November 2, the members of the board and representatives of Deutsche Bank discussed the offshore drilling industry in relation to potential merger and acquisition activity, the competitive landscape in the offshore drilling industry and several potential transactions, one of which included Pride. The board also met in executive session with representatives of Deutsche Bank to address various questions and comments regarding potential merger and acquisition activity. The board then authorized management to pursue initial discussions and take preliminary actions relating to a potential combination with Pride, including entry into a confidentiality agreement and negotiation of an engagement letter with Deutsche Bank.

On November 2, 2010, Messrs. Raspino, Voegele and Brady K. Long, vice president, general counsel and secretary of Pride, had a telephonic conference with Mr. Trøim. Mr. Raspino stated that he had discussed the matter with the Pride board of directors, and advised that the board remained open to receiving a written proposal from Seadrill. Mr. Raspino noted that all discussions with Seadrill over the past several years had been general in nature, with no specific proposal ever having been provided by Seadrill. Mr. Raspino stated that the board would fully consider any proposal made by Seadrill. Mr. Raspino discussed the principal topics that Seadrill should include in any such proposal, including the amount and form of consideration, financing, conditions to the transaction, board and management of the combined company, timeline for conducting due diligence, signing a definitive agreement and closing, and strict confidentiality. Mr. Raspino informed Mr. Trøim that Pride had been approached by other competitors and that Seadrill should put its best offer on the table for an acquisition of Pride. Mr. Trøim stated that Perella Weinberg Partners LP (“PWP”) was acting as Seadrill’s financial advisor and would be available for discussions with Pride’s board and financial advisor.

During an industry conference on November 10 and 11, 2010, Mr. Raspino met at separate times with each of Mr. Rabun, the chief executive officer of each of Company A and Company B and a representative of another industry participant. At their meeting, Mr. Rabun and Mr. Raspino continued their discussion of the strategic benefits of scale and critical mass, the companies’ shared core values and other potential benefits of a strategic combination. The chief executive officer of Company B expressed to Mr. Raspino a potential interest in an acquisition of Pride involving mostly cash, but suggested that a price above approximately $37 per share would be quite expensive. The chief executive officer of Company A expressed to Mr. Raspino a potential interest in a merger of equals transaction.

On November 16, 2010, Mr. Rabun sent a letter to Mr. Raspino advising him that the Ensco board of directors authorized Mr. Rabun to proceed with discussions regarding the possibility of combining Pride and Ensco. Mr. Rabun stated his expectation that the consideration would represent a premium to Pride stockholders consistent with that of recent acquisitions in the oil and gas services industry and would consist of a mix of cash and newly issued shares of Ensco, which would permit Pride stockholders to receive up-front value coupled with an ability to participate in the upside potential in the combined company.

Also on November 16, 2010, Mr. Fredriksen sent a letter to Mr. Raspino setting forth the proposed terms of a combination of Pride and Seadrill. The proposed terms indicated a price of $37 per share, and included a right of Pride stockholders to elect to receive for each Pride share $37 in cash or 1.168 Seadrill shares, subject to proration if more than 30% of the shares elected to receive cash. The proposed consideration represented an approximately 15% premium to the closing price of Pride’s common stock on November 15, 2010. Pride would have the right to nominate three of the eight members of the company’s board of directors. The letter acknowledged Pride’s need to conduct due diligence of Seadrill in light of the substantial portion of the consideration in the form of Seadrill stock and that Seadrill stood ready to accommodate due diligence in a timely manner. The letter also noted that Seadrill would require due diligence with respect to Pride.

On November 22, 2010, the Pride board of directors met with management and Pride’s financial and legal advisors. At the meeting, the Seadrill and Ensco letters were discussed in preliminary terms. The board was informed that management and Pride’s advisors would provide a more comprehensive analysis of the proposals at the regularly scheduled board meetings on December 9 and 10.

On November 23, 2010, Mr. Rabun had a telephone conference with Mr. Raspino to discuss the November 16 letter sent by Mr. Rabun. Mr. Raspino requested additional information on Ensco’s fleet and the jackup market for his discussions with the Pride board.

On November 24, 2010, Mr. Raspino sent Mr. Fredriksen correspondence informing him that Pride was targeting a board meeting late in the week of December 6 to discuss Seadrill’s November 16 letter and that Mr. Raspino intended to respond to Mr. Fredriksen shortly after the meeting.

On November 30, 2010, Mr. Rabun met with Mr. Raspino to discuss Ensco’s November 16 letter and the merits of a combination of the two companies. Mr. Rabun discussed his view of premium levels consistent with those of recent acquisitions in the oil and gas services industry as described in this letter. Mr. Raspino advised Mr. Rabun that the Pride board of directors would consider Ensco’s letter at its regularly scheduled meetings on December 9 and 10.

On December 1, 2010, Mr. Raspino, Mr. Voegele and other members of Pride’s senior management team met with the chief executive officer, the chief financial officer and other members of the senior management team of Company A. The management teams made presentations to each other regarding the respective company’s operations based on publicly available information. No specifics of a transaction were discussed.

At its regularly scheduled meeting on December 10, 2010, the Pride board of directors met with management and its legal and financial advisors. At the meeting, Baker Botts and Wachtell Lipton discussed with the directors their fiduciary duties. Management reviewed with the board the proposals made by Seadrill and Ensco on November 16, and representatives of Goldman Sachs reviewed its preliminary financial analyses of the proposals. Also discussed were possible combination transactions with other industry participants, including Company A, Company B and Company C. Management and the board discussed various financial metrics applicable to the possible transactions. The board authorized management to explore transactions with both Ensco and Seadrill and to conduct due diligence regarding potential transactions with both companies.

On December 13, 2010, Mr. Rabun had a telephone conference with Mr. Raspino. Mr. Raspino stated that the Pride board had reviewed Ensco’s proposal based on publicly available data and that the Pride board had authorized him to explore with Ensco the possibility of a business combination transaction on the basis of Ensco’s November 16 letter and the prior conversations and to initiate mutual due diligence. Mr. Raspino asked that Ensco send a proposed confidentiality agreement. Mr. Rabun advised Mr. Raspino that Ensco would need to perform preliminary due diligence before an initial proposal of principal terms could be submitted to Pride.

Ensco sent a draft confidentiality agreement to Pride on December 14, 2010. The draft confidentiality agreement included, among other provisions, a requirement that Pride negotiate exclusively with Ensco for a period of 45 days. During that day, at the direction of Ensco and Pride, representatives of Deutsche Bank and Goldman Sachs discussed the timing of a possible business combination transaction, an exchange of priority diligence lists, a framework for diligence and diligence-related matters.

Also on December 14, Messrs. Raspino and Long held a telephone conference with Messrs. Fredriksen and Trøim. Mr. Raspino informed them that the Pride board had reviewed Seadrill’s proposal based on publicly available data and that the board had authorized Mr. Raspino to explore a possible transaction. Mr. Raspino expressed an interest to meet with Seadrill representatives to explore a transaction and conduct due diligence. Mr. Raspino requested that Seadrill provide a list of the due diligence that Seadrill would require as referenced in its November 16 letter. Mr. Raspino noted that Pride’s analysis was based on only public data and, accordingly, Pride would need to conduct due diligence of Seadrill as acknowledged by Seadrill in its letter and would send Seadrill a list of requested information shortly. Mr. Raspino noted that the exchange of nonpublic information would be covered by a typical confidentiality agreement to be entered into by the companies. Mr. Trøim suggested that Pride instead meet with PWP, as Seadrill was not interested in participating in extensive due diligence meetings. Mr. Trøim indicated uncertainty as to whether Seadrill’s November 16 proposal was tied to a fixed exchange ratio or a fixed share price. Mr. Trøim requested that Pride agree to a period of exclusivity with Seadrill and stated that Seadrill would not be interested in pursuing a transaction without exclusivity. Mr. Trøim also requested a written response to the November 16 letter.

On December 16, 2010, the Ensco board of directors held an informal teleconference and discussed the status of the discussions with Pride. Mr. Rabun informed the board of his conversations with Mr. Raspino and the board authorized Mr. Rabun to continue the negotiations with Mr. Raspino.

On December 17, 2010, the Pride board of directors met with management to discuss the status of the discussions with Ensco and Seadrill. Mr. Raspino informed the board of his conversations with Mr. Rabun and the board authorized Pride to continue due diligence and authorized Mr. Raspino to continue the negotiations with Mr. Rabun. The board also discussed the appropriate response to Seadrill.

On December 18, 2010, Ensco and Pride executed a confidentiality agreement. The agreement included customary provisions for the confidentiality of discussions and the exchange of information. It also included a mutual standstill agreement effective for 18 months that would be terminated upon the occurrence of certain events including the commencement by a third party of a tender offer to acquire voting stock of a party to the confidentiality agreement representing 20% or more of the voting securities of such party and the agreement of a party to enter into a business combination or acquisition transaction involving a third party. The standstill agreement precluded either party, without the prior written invitation of the other party’s board of directors or chief executive officer, from taking various actions, including acquiring or proposing to acquire securities or derivative securities of the other party, participating in a proxy solicitation concerning the other party or proposing a business combination transaction with the other party. The agreement did not include a provision requiring Pride to negotiate exclusively with Ensco.

On December 20, 2010, Mr. Raspino sent a letter to Messrs. Fredriksen and Trøim as requested by Seadrill in the December 14 conference call to reiterate the discussions on that call. The letter set forth the proposed next steps, which were consistent with Seadrill’s November 16 letter and customary for transactions involving a significant amount of stock of the acquiring company. The letter stated that the Pride board continued to be open to considering any opportunity that could be compelling for all of Pride’s stockholders and that, to the extent Seadrill would like Pride to complete its evaluation of the proposal, Pride would be willing to proceed with a meeting and mutual due diligence as Seadrill suggested in its November 16 letter.

Also on December 20, 2010, the chief executive officer of Company A sent Mr. Raspino correspondence expressing interest in continuing the discussions regarding a possible transaction, which had previously concerned a merger of equals. No specific terms were provided.

On December 21, 2010, representatives of Goldman Sachs called PWP to discuss the process for conducting due diligence. PWP indicated that it would respond after it had discussed the matter with Seadrill.

Commencing December 22, 2010, officers and other representatives and advisors of Pride and Ensco conducted mutual due diligence. Representatives and advisors of the companies held a number of in person and telephonic meetings with each other, and each company established virtual data rooms to enable the parties and their representatives and advisors to engage in documentary due diligence.

On December 28, 2010, the Pride board of directors met with management to discuss the status of the discussions with Ensco and Seadrill.

On December 30, 2010, the Ensco board of directors held a special telephonic board meeting with participation of all members of the board, as well as members of management and representatives of Deutsche Bank and Baker & McKenzie LLP. Mr. Rabun described several recent senior management meetings with Pride that included diligence presentations by each company. Mr. Rabun also reviewed his discussions with Mr. Raspino, the preliminary financial analyses and models that had been developed based on different levels and mixes of stock and cash consideration, the due diligence undertaken by Ensco and Pride’s refusal to grant Ensco exclusivity rights. Mr. Rabun noted that progress had been made in refining Ensco’s financial models and analyses. Representatives of Deutsche Bank discussed certain financial aspects of the potential transaction with the members of the board. The directors discussed various questions and comments regarding the potential merger transaction with management and representatives of Deutsche Bank. Mr. Rabun noted that extended diligence, merger agreement and debt financing negotiations, regulatory submissions and preparation of proxy materials would proceed concurrently. The board reviewed a draft of an expression of interest letter and related summary of proposed terms, discussing various aspects of the drafts in general and the merger consideration in particular. The board authorized Mr. Rabun to submit a non-binding expression of interest letter and summary of proposed terms

to Pride, which would reflect an implied value of $39.00 per share, a mix of 35% cash and 65% shares, and one or two board seats. After excusing the representatives of Deutsche Bank from the meeting, Mr. Rabun described the negotiations with Deutsche Bank regarding terms of engagement of Deutsche Bank to serve as exclusive financial advisor to Ensco for the potential transaction.

On December 31, 2010, Mr. Rabun sent a letter to Mr. Raspino that set forth an indicative proposal of the terms upon which Ensco proposed to enter into an agreement to combine the companies. The letter proposed merger consideration for Pride stockholders consisting of 0.4778 Ensco ADSs and $13.65 per share of Pride common stock, which represented a value of $39.00 per share based on the closing price of Ensco ADSs as of December 30, 2010 and an approximately 18% premium to the closing price of Pride’s common stock as of that same date. The letter indicated that each company’s senior management would have good opportunities with the combined company. The proposal included a requirement that Pride negotiate exclusively with Ensco for a period of 21 days after entering into a written agreement to such effect to be negotiated between the parties. Pride representatives subsequently advised Ensco representatives that Pride would not be in a position to enter into any exclusive negotiating arrangement.

On January 5, 2011, the Pride board of directors met with management and its financial and legal advisors. At the meeting, the board was provided an update on the status of discussions with Ensco, Seadrill, Company A and Company B. Management reviewed the due diligence completed to date and representatives of Goldman Sachs reviewed its preliminary financial analyses of the proposal by Ensco.

On January 6, 2011, Mr. Rabun had a telephone conference with Mr. Raspino to discuss the reaction of the Pride board to Ensco’s indicative proposal. Mr. Raspino stated that the Pride board generally reacted favorably to the indicative proposal and Ensco’s approach to the process. However, Mr. Raspino stated that price and a number of other issues regarding the proposal would need to be discussed further. Mr. Raspino indicated in general terms that Pride would require a higher price, and Messrs. Raspino and Rabun discussed the flexibility in the mix of stock and cash proposed in the December 31 letter and Pride’s proportional representation on the combined company’s board based on the pro forma share ownership of each company’s shareholders in the combined company. No agreement was reached. They did not discuss any of the other items in the indicative proposal, but Mr. Raspino stated the Pride board authorized management to proceed with full diligence and preliminary negotiation of definitive documents.

On January 7, 2011, the Ensco board of directors held a special telephonic board meeting with participation of all members of the board, as well as members of management and representatives of Deutsche Bank and Baker & McKenzie. Mr. Rabun provided an update on the proposed transaction with Pride, with emphasis upon developments following submission of the expression of interest and summary of proposed terms on December 31, 2010. Mr. Rabun advised that he received initial feedback from Mr. Raspino, who had questions regarding the proposed merger consideration and the board composition of the merged company. Deutsche Bank representatives commented that they had a similar discussion with their counterparts at Goldman Sachs earlier in the week. The Ensco board then discussed with management and representatives of Deutsche Bank the points that were raised during the telephone conversations between the respective chief executive officers. It was noted that initial due diligence requests had been prepared and that further meetings with representatives of Pride had been scheduled to be held in Houston. The board discussed the proposed terms for the merger and potential points of focus for diligence. Mr. Swent discussed the contemplated impact of the potential transaction on Ensco’s credit ratings and reported on the financing plan for the proposed transaction and the status thereof. Michael B. Howe, Ensco’s Treasurer, described bridge financing discussions with potential lenders. Following deliberation, the board authorized management to continue moving forward with the process and approved the proposed engagement of Deutsche Bank as Ensco’s financial advisor in respect of the potential merger with Pride.

On January 10, 2011, responding to the December 21, 2010 discussions, PWP called representatives of Goldman Sachs to advise that Seadrill was willing to conduct mutual due diligence and to request that Pride provide its due diligence request list. At the direction of Pride, Goldman Sachs sent the initial due diligence request list to PWP on January 12, 2011.

On January 11, 2011, Mr. Rabun met with Mr. Raspino to discuss the status of due diligence and the path forward while both were attending an industry event.

On January 14, 2011, Mr. Rabun held an informal teleconference with the members of the Ensco board of directors, Ensco management and representatives of Deutsche Bank and Baker & McKenzie. During the teleconference, the participants reviewed the progress and findings of the legal, financial and operational due diligence which had been conducted, discussed potential synergies that would result from the combination of Ensco and Pride and considered the financial and rating agency reactions to such a combination and associated matters. Deutsche Bank representatives reviewed certain financial models and assumptions, described communications with Pride’s financial advisor Goldman Sachs and commented on various aspects of the potential merger of Ensco and Pride. It was the consensus of the board and management that it would be appropriate to further consider the potential combination of the two companies and to proceed with preparation of a draft merger agreement.

On January 16, 2011 Baker & McKenzie delivered a draft of the proposed merger agreement to Baker Botts. The terms of the proposed merger agreement were generally consistent with the terms of the merger agreement as finally executed by the parties but did not specify an amount of merger consideration or the number of board seats that would be filled by designees of Pride. The proposed agreement contemplated a transaction that would be treated as a reorganization qualifying under Section 368(a) of the U.S. Internal Revenue Code of 1986, as amended, provided for an election by Pride stockholders between cash and stock consideration and included conditions to closing relating to the receipt by Ensco of financing for the transaction and a limit on the number of Pride shares for which valid demands for appraisal remained effective. The proposed merger agreement included covenants restricting Pride’s ability to change its board recommendation or solicit competing transactions and, while not specifying a specific dollar figure for the termination fee to be payable by Pride, provided that the amount of such termination fee would be 3.5% of Pride’s equity value to be determined at the time of signing of the merger agreement.

On January 18, 2011, PWP called representatives of Goldman Sachs after consulting with Seadrill regarding Pride’s initial due diligence request list. PWP indicated that Seadrill would begin compiling the information to respond to the request on the expectation that the due diligence process would be reciprocal. PWP reiterated Seadrill’s position that Pride agree to negotiate exclusively with Seadrill. On January 19, at the direction of Pride, representatives of Goldman Sachs called PWP to discuss Pride’s need to conduct a full due diligence review of Seadrill to support its valuation analysis and advised PWP that Pride would not be in a position to enter into any exclusive negotiating arrangement.

On January 18, 2011, a stockholder of Pride called to inform Pride that it would make an HSR filing with respect to Pride and would propose a slate of directors for the upcoming annual stockholders meeting. The stockholder requested a meeting with Pride management, which was held on January 21. On January 19, counsel for the stockholder notified Pride of its HSR filing and requested various materials in connection with a possible nomination of directors. Over the next two weeks, Pride and its legal counsel had various discussions and correspondence with the stockholder and its counsel regarding Pride, the director nomination process and the HSR filing.

On January 19, 2011, the Pride board of directors met with management and its financial and legal advisors. At the meeting, the board was provided an update on the status of discussions with Ensco and Seadrill and the stockholder matters referenced in the preceding paragraph.

In late January, Mr. Trøim called representatives of Goldman Sachs to reiterate Seadrill’s continued interest in a potential transaction, its expectation that due diligence would be reciprocal, and that a decision would need to be made as to direction by mid-February to enable Seadrill to make decisions regarding directors. Representatives of Goldman Sachs then communicated Mr. Trøim’s message to Pride. Pride assumed that the reference to a mid-February deadline was a reference to the February 17 deadline for director nominations under Pride’s bylaws.

On January 21, 2011, Baker & McKenzie, Baker Botts and Wachtell Lipton had a telephone conference to discuss initial comments to the draft Ensco merger agreement, which were confirmed by email the next day. On

January 24, Baker & McKenzie, Richards, Layton & Finger, special Delaware counsel to Ensco, Baker Botts and Wachtell Lipton discussed the draft of the merger agreement and the initial comments to the agreement.

In the January 21 and January 24 discussions, counsel for Pride addressed, among other concerns, their objections to the proposed financing condition and the condition regarding the percentage of Pride stockholders demanding appraisal rights, the requirement that confidentiality agreements that Pride would be permitted to enter into with potential competing bidders would be required to include standstill provisions consistent with the standstill agreement entered into with Ensco, the period of prior notice that Ensco would require before the Pride board of directors could change its recommendation, the amount of time during which Ensco could submit a revised proposal in response to a notice by Pride of its intent to terminate the merger agreement and enter into a superior proposal, the absence of reciprocal provisions restricting Ensco’s ability to change its board recommendation or solicit alternative transactions, the circumstances under which a termination fee would be payable and the absence of an adequate termination fee that would be payable under certain circumstances in the event that Ensco shareholders failed to approve the issuance of Ensco ADSs in connection with the merger. Counsel for Pride also suggested that the transaction be structured as a taxable merger without any election between cash and stock to simplify the structure and mitigate tax risk to the combined company.

On January 24, 2011, PWP called representatives of Goldman Sachs. PWP indicated that Seadrill was preparing due diligence materials in response to Pride’s January 12 request. PWP inquired about the process once the materials were provided to Pride. At the direction of Pride, representatives of Goldman Sachs stated that Pride could not commit to a specific time frame for responding, given that no materials had yet been provided, but that Pride would respond promptly once materials were received.

On January 25, Baker & McKenzie sent a revised draft of the merger agreement to Baker Botts. Over the next 10 days, counsel to the parties had various discussions and correspondence regarding comments to the draft. In addition to the issues noted below, other principal issues involved increasing deal certainty by having the no solicitation covenant apply reciprocally to Ensco and by Ensco’s agreeing that Delaware Sub would agree to pay the same termination fee in the same circumstances as would apply to Pride. The parties also discussed the provisions dealing with the treatment of employees of Pride after the merger.

As contemplated by the letter agreement between Pride and Goldman Sachs, dated August 10, 2007, Pride and Goldman Sachs entered into a letter agreement effective as of January 26, 2011, pursuant to which Pride engaged Goldman Sachs to act as its financial advisor in connection with the potential acquisition of Pride or other similar extraordinary transactions involving Pride or the acquisition of Pride.

On January 27, 2011, the Ensco board of directors held a special telephonic board meeting with participation of all members of the board, as well as members of management and representatives of Deutsche Bank and Baker & McKenzie. Mr. Rabun reported that the business and legal due diligence had progressed substantially and described the Pride comments to the merger agreement and the plan for continued negotiations. Mr. Swent reviewed revised financial models prepared by management that were reconciled to models previously reviewed with the board, noting that budget information recently had been received from Pride. He noted that due diligence would continue regarding capital expenditures. Representatives of Deutsche Bank reviewed with the board various financial analyses and other considerations relating to the proposed transaction. The Deutsche Bank presentation concluded with a review of certain terms of the proposed transaction, after which representatives of Deutsche Bank responded to questions and comments from the board. Mr. Howe described the proposed bridge financing arrangements and the progress in obtaining credit committee approval from affiliates of Deutsche Bank.

On January 31, 2011, Gerald Haddock, an Ensco director and chairman of Ensco’s audit committee, telephonically conferred with Francis S. Kalman, a Pride director and chairman of Pride’s audit committee, to discuss certain FCPA and regulatory compliance diligence matters.

On February 1, 2011, Mr. Raspino had a telephone conference with Mr. Rabun to further discuss the principal issues related to pricing and board representation in connection with the potential transaction. With respect to pricing, Mr. Raspino indicated that Ensco should make its highest possible proposal for consideration by the Pride board. Mr. Raspino again suggested that Pride should have proportional representation on the

combined company’s board based on the pro forma share ownership of each company’s shareholders in the combined company. No agreement was reached.

On February 2, 2011, PWP provided to Pride an initial package of due diligence materials of Seadrill in partial response to Pride’s request. On February 4, Mr. Raspino sent a letter to Mr. Fredriksen acknowledging receipt of the materials and requesting again the due diligence request list of information that Seadrill would require. Mr. Raspino indicated that the Pride board continued to be open to considering any opportunity that would be compelling for its stockholders and that Mr. Raspino was available to meet with Mr. Fredriksen, as he had done many times in the past with Messrs. Fredriksen and Trøim, if it would further advance that goal. Later that day, Mr. Raspino sent Messrs. Fredriksen and Trøim a confidentiality agreement executed by Pride that did not have any standstill provisions.

Also on February 2, 2011, the Pride board of directors met with management and representatives of Goldman Sachs, Baker Botts and Wachtell Lipton. At the meeting, Baker Botts and Wachtell Lipton reviewed with the Pride directors their fiduciary duties. Management discussed with the board various financial metrics and analyses regarding Pride, Ensco and the pro forma combined company. Management also discussed with the board the results of the due diligence review with respect to Ensco. Management, together with Baker Botts and Wachtell Lipton, discussed the significant business issues contained in the most recent draft of the merger agreement, including with respect to price, mix of consideration, board representation, conditionality, deal certainty and employee matters. The board discussed with management the status of discussions with Seadrill, Company A and Company B, as well as possible transactions with other industry participants, including Company C. Representatives of Goldman Sachs reviewed its preliminary financial analyses of the proposed merger.

On February 4, 2011, Baker & McKenzie sent a revised draft of the merger agreement to Baker Botts, which, in addition to the matters that had been previously discussed, included a modification to the definition of “material adverse effect” that would include a breach or violation, or occurrence reasonably likely to result in a breach or violation, of Pride’s deferred prosecution agreement with the U.S. Department of Justice in connection with Pride’s settlement of potential violations of the FCPA if such breach, violation or occurrence would permit the Department of Justice to extend the term of such agreement or pursue any criminal charges or prosecution or any civil or administrative action that was not filed as a result of the deferred prosecution agreement.

On February 4, 2011, the Ensco board of directors held a special telephonic board meeting with participation of all members of the board, as well as members of management and representatives of Deutsche Bank and Baker & McKenzie. Mr. Rabun reported that due diligence had progressed substantially and advised that comments had been received from Pride on the proposed merger agreement. Mr. Rabun discussed various aspects of the diligence undertaken by Ensco and Pride. Mr. Haddock described his telephone conversation with Mr. Kalman. Mr. Rabun described a recent telephone conversation with Mr. Raspino. Mr. Rabun summarized the principal outstanding issues in relation to the proposed merger agreement, and called upon Alan Harvey of Baker & McKenzie to provide an overview of the contemplated transaction. Mr. Harvey reviewed the contemplated merger structure and consideration composed of a mix of cash and Ensco shares and also discussed the potential tax treatment of the merger consideration for the Pride stockholders. He described the principal open issues. Mr. Rabun described the process that would be employed, if the board determined to proceed. Representatives of Deutsche Bank reviewed updated materials which had been distributed to the board. After noting that there were no major changes since the last discussion with the board, representatives of Deutsche Bank reviewed various updated financial analyses and sensitivities, the competitive landscape and other illustrative combinations with Pride. The board discussed the dynamics of recent developments, other potential interested parties and due diligence, and further reviewed key issues pertaining to the merger agreement. Mr. Rabun led a discussion on negotiating strategy. Following discussion with participation by the financial and legal advisors, Mr. Rabun was authorized to present a specific merger proposal to Pride involving designated merger consideration in cash and stock and two Pride directorships on the combined company board. The board met in executive session to discuss social, organizational, severance and retentive compensation matters.

On February 4, 2011, Mr. Rabun had a telephone conference with Mr. Raspino, during which Mr. Rabun stated that Ensco was willing to increase the cash portion of the consideration by $1.08 per share to $14.73 per share, with the same exchange ratio of 0.4778 Ensco ADSs per Pride share as set forth in the December 31

proposal. The proposed consideration represented a price of $41.00, or an approximately 20% premium to the closing price of Pride’s common stock as of February 3, based on the closing price of Ensco ADSs on that date.

On February 5, 2011, Mr. Raspino advised Mr. Rabun that, based on the level of premium previously discussed and the favorable results of due diligence, the Pride board had expected a price in the $42.00 per share range, as well as three board seats. Mr. Raspino also discussed the removal of the new provision relating to the deferred prosecution agreement that had been proposed for inclusion in the definition of material adverse effect in the merger agreement. Mr. Rabun indicated that Ensco would not require the proposed provision.

On February 5, 2011, the Ensco board of directors held a special telephonic board meeting with participation of all members of the board, as well as members of management and representatives of Deutsche Bank and Baker & McKenzie. Mr. Rabun advised that he had received an initial response to Ensco’s revised proposal from Mr. Raspino, who requested that three Pride directors serve on the board of the combined company. Mr. Rabun also advised that Mr. Raspino indicated that the Pride board required a somewhat higher price. The board determined that it would be inappropriate to modify the proposal that had been submitted to Pride until such time as the Pride board had an opportunity to fully consider the matter. The meeting was adjourned until Ensco received a response to its proposal.

On February 5, 2011, the Pride board of directors met with management and Pride’s financial and legal advisors to discuss the Ensco proposal and the terms of the current draft of the merger agreement. The board indicated to Mr. Raspino that it would support a transaction if, among other matters, it offered a value that was a 21% premium to the closing price of Pride common stock on February 4, 2011, or $41.60 per share. The board authorized Mr. Raspino to continue to seek additional board representation on Ensco’s board following the merger so long as it would not diminish the value that Ensco was prepared to offer.

Mr. Raspino called Mr. Rabun that day to propose a price with a value equal to a 21% premium to the closing price of Pride common stock on February 4, 2011, or $41.60 per share, and that Pride directors would have three seats on the combined company’s board.

The Ensco telephonic board meeting was reconvened later that day. Mr. Rabun reported on his call with Mr. Raspino. The Ensco board discussed the feedback received from Mr. Raspino and considered the merger consideration issue in consultation with Ensco’s financial advisor. Representatives of Deutsche Bank then discussed certain considerations that it would take into account in rendering a fairness opinion. Following discussion with representatives of Deutsche Bank regarding the merger consideration, the board determined that its initial proposal to provide Pride two seats on the combined company board should remain unchanged. The board determined that Pride should be advised (1) that the proposed additional merger consideration would be satisfactory if comprised of $15.60 in cash and 0.4778 Ensco ADSs, each whole ADS representing one Class A ordinary share, for each share of Pride common stock and (2) the Pride directors would have two seats on the combined company’s board. Mr. Rabun was authorized to convey the board’s determination to Mr. Raspino for presentation to the Pride board of directors. The Ensco board entered into executive session to enable the board to discuss certain employment and compensation matters.

Mr. Rabun called Mr. Raspino to convey the Ensco board’s determination that (1) the proposed additional merger consideration would be satisfactory if comprised of $15.60 in cash and 0.4778 Ensco ADSs for each share of Pride common stock and (2) the Pride directors would have two seats on the combined company’s board. After discussions with the chairman of the Pride board of directors and Pride’s financial and legal advisors, Mr. Raspino called Mr. Rabun to inform him that those proposed terms were acceptable to the Pride board and that the respective counsel should work to finalize the documentation.

Mr. Rabun again reconvened the Ensco telephonic board meeting later that day. Mr. Rabun advised that Mr. Raspino had informed him that Ensco’s proposed terms for the merger were acceptable to the Pride board, subject to resolution of the few remaining open issues in agreement. The final approval would be forthcoming following a Pride board meeting to be held on the following day. Mr. Harvey reviewed the proposed merger agreement and summarized the terms of the proposed merger, pursuant to which the owner of each share of Pride common stock would be entitled to receive per share compensation composed of $15.60 in cash and 0.4778 Ensco ADSs, each whole ADS representing one Class A ordinary share. He then described the

termination provisions of the merger agreement, noting that they entailed a break-up fee of $260 million, which is reciprocal, contained fiduciary outs and a reciprocal $50 million fee in the event either company’s shareholders fail to approve the transaction in the absence of a competing offer. Mr. Rabun noted that employee matters had also been addressed in his conversation with Mr. Raspino, resulting in an understanding that employees would generally be treated on a common basis. The board engaged in a general discussion with management and Ensco’s outside financial and legal advisors regarding the terms and conditions of the contemplated agreement. Helen Bradley of Baker & McKenzie LLP, described the board’s fiduciary duties in relation to the contemplated merger transaction, referring to her presentation to the board on August 3, 2010 regarding directors’ duties. Representatives of Deutsche Bank described the terms of the fairness opinion which would be delivered by Deutsche Bank and the financial terms of the merger agreement, and presented financial analysis with respect to Pride, Ensco and the combined company. Deutsche Bank then delivered its oral opinion to the Ensco board of directors, which was subsequently confirmed by delivery of a written opinion dated February 6, 2011, to the effect that, as of such date and based upon and subject to the matters set forth therein, the merger consideration comprised of $15.60 in cash and 0.4778 Ensco ADSs, each whole ADS representing one Class A ordinary share, to be paid in respect to each share of Pride common stock was fair, from a financial point of view, to Ensco. The full text of Deutsche Bank’s written opinion, dated February 6, 2011, which sets forth, among other matters, the assumptions made, matters considered and limitations, qualifications and conditions on the review undertaken by Deutsche Bank in connection with the opinion, is attached as Annex B. See “— Opinion of Deutsche Bank Securities Inc.”

Following review and discussion among the Ensco directors, the Ensco board unanimously determined the merger to be advisable and likely to promote the success of Ensco for the benefit of its shareholders and in the best interests of Ensco. The board unanimously approved the terms and conditions for the contemplated merger including the conversion of each Pride share into the right to receive $15.60 and 0.4778 Ensco ADSs, each whole ADS representing one Class A ordinary share. The board also approved the submission to Ensco shareholders of an ordinary resolution to approve the issuance and delivery of the ADSs in respect of Class A ordinary shares to Pride stockholders, the filing with the SEC of a registration statement to register Class A ordinary shares represented by ADSs pursuant to the Securities Act of 1933, as amended, the filing with the New York Stock Exchange of a listing application and a bridge commitment letter and related fee letter providing for an unsecured term loan bridge facility of $2.75 billion to fund, together with cash on hand, the cash portion of the merger consideration. Later on February 5, 2011, Mr. Rabun had a telephone conference with Mr. Raspino to discuss the Ensco proposal and the results of the Ensco board meeting.

On February 6, 2011, the Pride board of directors held a specially scheduled board meeting attended in person or telephonically by all members of the Pride board, as well as members of management and representatives of Goldman Sachs, Baker Botts and Wachtell Lipton. At the meeting, Baker Botts and Wachtell Lipton reviewed with the Pride board of directors its fiduciary duties. Baker Botts and Wachtell Lipton discussed with the board the principal terms and conditions of the merger agreement. Goldman Sachs presented its financial analyses of the proposed merger and delivered its oral opinion to the Pride board of directors, which was confirmed by delivery of a written opinion dated February 6, 2011, that, as of such date and based upon and subject to the limitations and assumptions set forth therein, the merger consideration to be received by the Pride stockholders (other than Ensco and its affiliates) pursuant to the merger agreement was fair, from a financial point of view, to such holders. See “— Opinion of Goldman, Sachs & Co.” The board discussed with management the strategic benefits of the transaction and compared the transaction to possible transactions with Seadrill and other industry participants. Mr. Raspino discussed his view of the principal benefits to Pride and its stockholders of the combination of the two companies and recommended, on behalf of management, that the board approve the transaction. See “— Recommendation of the Pride Board of Directors and Its Reasons for the Merger” for a discussion of such principal benefits of the transaction and for a discussion of the factors considered by the Pride board in concluding that the merger agreement and the transactions contemplated by the merger agreement are advisable and in the best interests of Pride and its stockholders, including the board’s belief that the merger represented superior value to Pride stockholders as compared with the potential stockholder value that might result from other strategic alternatives that might be available to Pride, including Pride’s remaining an independent public company and possible transactions with other industry participants. Upon the recommendation of the compensation committee of the board of

directors, the board approved certain matters with respect to the treatment of equity awards as provided in the merger agreement. Following review and discussion among the members of the Pride board of directors, the Pride board of directors unanimously determined that the merger agreement and the transactions contemplated by the merger agreement were advisable and in the best interests of Pride stockholders, and all of the Pride directors unanimously voted to approve the merger agreement and the transactions contemplated by the merger agreement.

On February 6, 2011, Mr. Rabun had a telephone conference with Mr. Raspino to discuss the results of the Pride board meeting.

Over the course of the day on February 6, 2011, the merger agreement was finalized and was executed and delivered by Ensco and Pride that evening.

On February 7, 2011 and shortly before the public announcement of the merger, Mr. Trøim e-mailed Mr. Raspino addressing the confidentiality agreement and Seadrill’s continuing interest in pursuing a transaction with Pride.

On February 7, 2011, Ensco and Pride issued a joint press release, before the commencement of trading on the NYSE, announcing the transaction, and senior management of Ensco and Pride held a joint conference call. Various communications and the merger agreement were filed with the SEC on February 7, 2011 and thereafter.

On February 10, 2011, representatives of Baker & McKenzie and Citibank, the exchange agent for the merger consideration, conferred by telephone to discuss the certification and settlement procedures with respect to shares of Pride common stock beneficially owned in book-entry form by certain U.K. residents in order to provide reasonable assurances of compliance with the U.K. Prospectus Rules. Citibank reported that the Depository Trust Company had indicated that the certification process would require a specified deadline and that revisions would be necessary to the certification and exchange process with respect to settlement of book-entry shares. Over the next three weeks, representatives of Baker & McKenzie, Baker Botts, Wachtell Lipton and Citibank conferred several times to discuss potential amendments to the merger agreement to provide for an efficient certification, exchange and settlement process, and Baker & McKenzie provided drafts of revised language for the merger agreement, which were discussed by the parties.

On February 27, 2011, Baker & McKenzie sent Baker Botts a form of amendment to the merger agreement reflecting the negotiated language. On February 28, 2011, the Ensco board, at a regularly scheduled meeting, approved the amendment. On March 1, 2011, the Pride board approved the amendment by unanimous written consent, and the parties executed and delivered the amendment that day.

Recommendation of the Ensco Board of Directors and Its Reasons for the Merger

By vote at a meeting held on February 5, 2011, the Ensco board of directors unanimously determined that the merger agreement and the transactions contemplated by it are advisable and in the best interests of Ensco and its stockholders and approved the merger agreement and approved the issuance and delivery of Ensco ADSs pursuant to the merger agreement. The Ensco board of directors unanimously recommends that Ensco shareholders vote “FOR” approval of the issuance and delivery of Ensco ADSs pursuant to the merger agreement.

In deciding to approve the merger agreement and to recommend that Ensco shareholders vote to approve the issuance and delivery of Ensco ADSs to Pride stockholders pursuant to the merger agreement, the Ensco board of directors consulted with Ensco’s management and financial and legal advisors and considered several factors.

Many of the factors considered favored the conclusion of the Ensco board of directors that the merger is advisable and in the best interests of Ensco and its stockholders. The Ensco board of directors considered a number of factors concerning the merger. The Ensco board of directors considered these factors as a whole

and without assigning relative weights to each such factor, and overall considered the relevant factors to be favorable to, and in support of, its determinations and recommendations. These factors included:


	•	that the merger would enhance Ensco’s asset base, customer opportunities and service offerings by creating the world’s second largest offshore drilling fleet, with 74 rigs spanning all of the strategic, high-growth markets around the globe;

	•	that the merger would lead to future business opportunities in strategic, high-growth markets, particularly Brazil and West Africa, two of the fastest-growing deepwater markets in the world.;

	•	that the addition of Pride’s assets would provide a substantial presence in deepwater drilling sector, with 21 deepwater drilling rigs, including seven rigs delivered since 2008 and another five rigs expected to be delivered between now and 2013, establishing the combined fleet as among the youngest and most capable in the industry;

	•	that the merger would provide a complementary fleet composition, geographic scope and customer base;

	•	that the merger would provide a combined estimated revenue backlog of approximately $10 billion;

	•	that Ensco management expects the merger to result in meaningful cost savings and operational synergies, estimated to be in excess of $50 million per year in 2012 and beyond;

	•	the merger is anticipated to be immediately accretive to Ensco’s earnings and cash flow;

	•	the terms of the merger agreement, the structure of the transaction, including the conditions to each party’s obligation to complete the merger, and the ability of the Ensco board of directors to terminate the agreement under certain circumstances;

	•	that the merger agreement provides that, under certain circumstances, Pride could be required to pay a termination fee of $260 million to Ensco and a fee of $50 million in other circumstances;

	•	the ability of Ensco and Pride to complete the merger, including their ability to obtain the necessary regulatory approvals and their obligations in connection with obtaining those approvals; and

	•	Deutsche Bank’s presentation to the Ensco board on February 5, 2011 and the oral opinion of Deutsche Bank to the Ensco board of directors on February 5, 2011, subsequently confirmed in a written opinion dated February 6, 2011, to the effect that, as of the date thereof and based on and subject to the assumptions, limitations, qualifications and conditions described therein, the merger consideration comprised of $15.60 in cash and 0.4778 Ensco ADSs, each whole ADS representing one Class A ordinary share, to be paid in respect of each share of Pride common stock was fair, from a financial point of view, to Ensco. The full text of Deutsche Bank’s written opinion, dated February 6, 2011, which sets forth, among other matters, the assumptions made, matters considered and limitations, qualifications and conditions on the review undertaken by Deutsche Bank in connection with the opinion, is attached as Annex B. Deutsche Bank’s opinion was addressed to, and for the use and benefit of, the Ensco board, does not address Ensco’s underlying business decision to engage in the merger, and is not a recommendation as to how any holder of Ensco ADSs or Class A ordinary shares should vote with respect to the merger. See “— Opinion of Deutsche Bank Securities Inc.”

The Ensco board of directors considered additional information concerning the merger. The Ensco board of directors considered this information as a whole and without assigning relative weights to each such item, and overall considered the relevant factors to be favorable to, and in support of, its determinations and recommendations. This information included:


	•	information concerning the financial condition, results of operations, prospects and businesses of Ensco and Pride provided by management of each of the companies, including the respective companies’ cash flows from operations, expected accretion to earnings and cash flow, recent performance of common stock and the ratio of Ensco ADSs price to Pride common stock price over various periods, as well as current industry, economic and market conditions;


	•	the earnings per share, price to earnings multiples and other market factors of both Ensco and Pride; and

	•	the results of Ensco’s business, legal and financial due diligence review of Pride.

The Ensco board of directors also considered a variety of risks and other potentially negative factors concerning the merger agreement and the transactions contemplated by it, including the merger. These factors included:


	•	that there are significant risks inherent in combining and integrating two companies, including that the companies may not be successfully integrated or that the expected synergies from combining the two companies may not be realized, and that successful integration of the companies will require the dedication of significant management resources, which will temporarily detract attention from the day-to-day businesses of the combined company;

	•	the effects on cash flows from operations and other financial measures under various modeling assumptions, and the uncertainties in timing and execution risk with respect to the anticipated benefits of the merger;

	•	the need to obtain additional debt financing to be able to pay the cash component of the merger consideration and the lack of a financing condition in the merger agreement;

	•	the negative effect on employee morale and cost of relocating the headquarters of its U.S. operations to be consolidated with Pride’s headquarters in Houston;

	•	that the merger agreement provides that, in certain circumstances, Delaware Sub could be required to pay a termination fee of $260 million to Pride and a fee of $50 million in certain other circumstances;

	•	that the merger might not be completed as a result of a failure to satisfy the conditions contained in the merger agreement, including failure to receive necessary regulatory approvals such as under the HSR Act;

	•	the potential that certain institutional holders of shares of Pride common stock may not be permitted by their investment policies or may not otherwise want to hold ADSs of a non-U.S. company and would, as a result, sell the Ensco ADSs in the open market shortly after the closing of the merger, which may have a short-term, negative effect on the market prices of Ensco ADSs;

	•	the possibility of losing key employees and skilled workers as a result of the merger and the expected consolidation of its U.S. headquarters in Houston;

	•	the possibility of customer overlap or that key customers may choose not to do business with the combined company; and

	•	other matters described under the caption “Risk Factors.”

This discussion of the information and factors considered by the Ensco board of directors in reaching its conclusion and recommendations includes all of the material factors considered by the board but is not intended to be exhaustive and is not provided in any specific order or ranking. In view of the wide variety of factors considered by the Ensco board of directors in evaluating the merger agreement and the transactions contemplated by it, including the merger, and the complexity of these matters, the Ensco board of directors did not find it practicable to, and did not attempt to, quantify, rank or otherwise assign relative weight to those factors. In addition, different members of the Ensco board of directors may have given different weight to different factors. The Ensco board of directors did not reach any specific conclusion with respect to any of the factors considered and instead conducted an overall analysis of such factors and determined that, in the aggregate, the potential benefits considered outweighed the potential risks or possible negative consequences of approving the merger agreement and the issuance and delivery of Ensco ADSs pursuant to the merger agreement. As of the date of this joint proxy statement/prospectus, there have been no material changes in the operations or performance of Ensco or in the financial projections for Ensco or Pride prepared by Ensco’s

management since February 6, 2011, and Ensco does not anticipate such changes to occur prior to the general meeting of Ensco shareholders.

It should be noted that this explanation of the reasoning of the Ensco board of directors and all other information presented in this section is forward-looking in nature and, therefore, should be read in light of the factors discussed under the heading “Cautionary Statement Concerning Forward-Looking Statements.”

Recommendation of the Pride Board of Directors and Its Reasons for the Merger

By a vote at a meeting held on February 6, 2011, the Pride board of directors unanimously determined that the merger agreement and the transactions contemplated by the merger agreement were advisable and in the best interests of Pride and its stockholders and approved the merger agreement and the transactions contemplated thereby, including the merger. The Pride board of directors unanimously recommends that the Pride stockholders vote FOR the proposal to adopt the merger agreement at the Pride special meeting.

In evaluating the merger, the Pride board of directors consulted with Pride’s management and legal and financial advisors and, in reaching its determination and recommendation, the Pride board of directors considered a number of factors. The Pride board of directors also consulted with outside legal counsel regarding its fiduciary duties, legal due diligence matters and the terms of the merger agreement.

Many of the factors considered favored the conclusion of the Pride board of directors that the merger agreement and the transactions contemplated by the merger agreement are advisable and in the best interests of Pride and its stockholders, including the following:


	•	The aggregate value and composition of the merger consideration to be received by Pride stockholders in the merger.

	•	That the merger consideration with a value of $41.60 per share of Pride common stock, based upon the closing price of Ensco ADSs on February 4, 2011 (the last trading date before the date of the Pride board meeting), represented a premium of:


	•	21% to the closing price of Pride common stock on the same date; and

	•	26%, 38% and 45% to the one-month, six-month and 12-month average closing prices of Pride common stock.


	•	The potential stockholder value that might result from other alternatives available to Pride, including the alternative of remaining as an independent public company, considering, in particular, the potential for Pride stockholders to benefit from any future earnings growth of Pride and continued costs, risks and uncertainties associated with continuing to operate as a public company.

	•	The belief of the Pride board of directors that the shared core values of the two companies, including those of safety, employee development, ethics, operational excellence and customer satisfaction, will assist in integration of the companies, enhance the reputation of the combined company as an “employer of choice” and its ability to attract, retain and develop a high quality workforce and enhance customer service going forward.

	•	That the merger would enhance Pride’s assets, customer opportunities and service offerings by creating the world’s second largest and second youngest fleet of deepwater rigs, with 21 rigs and an average age of approximately seven years, and the second largest fleet of offshore drilling rigs, with 74 rigs spanning the world’s strategic, high-growth markets, including the largest active fleet of jackups, all independent leg design with many equipped with high specification features increasingly preferred by clients.

	•	The diversity of the combined company’s assets, customers and geographic areas of operations.

	•	The prospects of the combined company, including the value of critical mass and the potential for the combined company to have a stronger competitive position, greater opportunities for growth and an


		enhanced ability to meet the increasingly stringent regulatory requirements worldwide than Pride would have operating independently in the offshore drilling industry, particularly given events related to the Macondo well incident.


	•	The board’s familiarity with, and understanding of, Pride’s business, assets, financial condition, results of operations, current business strategy and prospects.

	•	The financial analyses presented by Goldman Sachs at the Pride board meeting held on February 6, 2011, and the oral opinion of that firm delivered to Pride’s board on that date, which was confirmed by delivery of a written opinion dated February 6, 2011, that, as of such date and based upon and subject to the limitations and assumptions set forth therein, the merger consideration to be received by the Pride stockholders (other than Ensco and its affiliates) pursuant to the merger agreement (which for purposes of this paragraph refers to the original merger agreement dated February 6, 2011) was fair, from a financial point of view, to such holders, as more fully described below under “— Opinion of Goldman, Sachs & Co.” The full text of the written opinion of Goldman Sachs, dated February 6, 2011, which sets forth assumptions made, procedures followed, matters considered and limitations on the review undertaken in connection with the opinion, is attached as Annex C to this joint proxy statement/prospectus.

	•	Information and discussions regarding Ensco’s business, assets, financial condition, results of operations, business plan, financial strategy, customer relationships, management and prospects, including the size and scale of the combined company and the expected pro forma effect of the merger on the combined company’s global rig fleet, potential customers, cost of capital, earnings, cost structure and capitalization, and the belief that the larger combined company would have more financial resources to pursue additional, meaningful growth while high-grading its fleet.

	•	The possibility that the combined company would achieve a higher trading multiple than Pride as a stand-alone company and would be more attractive to a broader group of investors because of the size, competitive position, asset quality and worldwide presence of the combined company.

	•	That the merger consideration is payable in cash and Ensco ADSs, providing Pride stockholders with the opportunity to participate in the equity value of the combined company following the merger while at the same time providing immediate value through the cash component of the merger consideration, with Pride stockholders expected to hold approximately 38% of the combined company’s ADSs outstanding immediately after the merger and two Pride directors bringing their experience to the combined company’s board.

	•	That the merger agreement has no financing condition and the belief of the Pride board of directors, supported by the financing commitment letter, and established after consultation with Pride’s advisors regarding the terms and degree of conditionality of the financing commitment letter, that Ensco would be able to obtain the financing necessary to pay the cash portion of the merger consideration payable under the merger agreement.

	•	The belief of the Pride board of directors that the merger represented superior value to Pride stockholders as compared with the potential stockholder value that might result from other strategic alternatives that might be available to Pride, including possible transactions with Seadrill, Company A, Company B, Company C, other industry participants with which Pride has had discussions and other potential acquirers, taking into account, among other matters, (1) indications of value proposed or suggested by such participants as compared with the value of the merger consideration, and the board’s view of the low likelihood that value superior to the merger consideration was achievable, (2) the history of discussions with such participants, (3) the likelihood that any of them would offer a transaction more advantageous to Pride stockholders than the merger, (4) the likelihood that an agreement could be reached regarding such an alternative transaction on a timely basis, the likelihood that any transaction agreed to would be consummated and the risk that pursuing such an alternative transaction would render a transaction with Ensco unavailable, (5) the risks to Pride if such an


		alternative transaction was not agreed to or not consummated, (6) the possible detrimental effects of public disclosure of Pride’s exploring possible business combination transactions and (7) the following:


	•	Information and discussions regarding Seadrill’s business, assets, financial condition, leverage, results of operations, financial strategy, customer relationships, management and prospects, as well as the status, nature and uncertainty of Pride’s discussions with Seadrill, including consideration of the matters with respect to Seadrill described under “— Background of the Merger” above, and discussions with respect to the relative value of Seadrill equity compared with Ensco equity and the equity of other offshore drillers.

	•	Consideration of the analyses presented to the Pride board regarding Company A, Company B, Company C, other industry participants with which Pride has had discussions and the potential for other interested acquirers and the substance of the discussions with Company A, Company B, Company C and such other industry participants.


	•	That Ensco is headquartered in a jurisdiction that has a favorable tax regime and an extensive network of tax treaties, which can allow the combined company to achieve a global effective tax rate comparable to our competitors, and that Ensco is moving its U.S. headquarters to Houston from Dallas, thereby allowing the employees of Pride more easily to contribute to the success of the combined company.

	•	That Ensco currently pays regular quarterly cash dividends on its Class A ordinary shares ($0.35 per share since the second quarter of 2010) while Pride does not currently pay a dividend and that, after the proposed transaction, Pride’s stockholders will be entitled to receive dividends, if any, paid by Ensco on its Class A ordinary shares.

	•	The review by the Pride board of directors with its legal and financial advisors of the structure of the merger and the financial and other terms of the merger agreement, including the parties’ representations, warranties and covenants, the conditions to their respective obligations and the termination provisions, as well as the likelihood of consummation of the merger and the Pride board’s evaluation of the likely time period necessary to close the transaction. The Pride board of directors also considered the following specific aspects of the merger agreement:


	•	The combination of stock and cash consideration contemplated by the merger agreement.

	•	Pride’s right to designate two current non-employee directors to the board of directors of Ensco.

	•	The nature of the closing conditions included in the merger agreement, including the market, industry-related and other exceptions to the events that would constitute a material adverse effect on either Pride or Ensco for purposes of the agreement, as well as the likelihood of satisfaction of all conditions to the consummation of the merger.

	•	Ensco’s agreement to use reasonable best efforts to obtain approvals of applicable antitrust and competition authorities, including disposing of assets and limiting the combined company’s freedom of action, except for such matters which, in the reasonable good faith judgment of both Ensco and Pride, are reasonably likely individually or in the aggregate to have a material adverse effect on either Ensco or Pride.

	•	Pride’s right to engage in negotiations with, and provide information to, a third party that makes an unsolicited written acquisition proposal, if the Pride board of directors determines in good faith, after consultation with its legal and financial advisors, that such proposal constitutes or could reasonably be expected to result in a transaction that is superior to the merger.

	•	Pride’s right to change its recommendation to vote in favor of the adoption of the merger agreement if it determines in good faith that the failure to take such action would be inconsistent with its fiduciary duties, subject to certain conditions (including considering any adjustments to the merger agreement proposed by Ensco and payment to Ensco of a $260 million termination fee if Ensco


		subsequently terminates the merger agreement under circumstances specified in the merger agreement).


	•	Pride’s right to terminate the merger agreement in order to accept a superior proposal, subject to certain conditions (including considering any adjustments to the merger agreement proposed by Ensco and payment to Ensco of a $260 million termination fee).

	•	The obligations of Pride and Ensco to hold their respective stockholders and shareholders meetings even if their respective boards change their recommendation of the merger.

	•	That termination fees of $260 million and $50 million, in each case, payable by Pride to Ensco under the circumstances specified in the merger agreement, were reasonable in the judgment of the Pride board of directors after consultation with its advisors.

	•	The obligation of Delaware Sub to pay to Pride $260 million and $50 million termination fees under reciprocal circumstances.

	•	The fact that Ensco’s obligation to close the merger is not subject to a financing condition or any condition related to the number of Pride stockholders seeking statutory appraisal rights.

	•	The obligation of Ensco to use its reasonable best efforts to take all actions necessary to consummate the financing provided for in the bridge commitment letter and, if such financing is unavailable, to use its reasonable best efforts to arrange to obtain alternate financing for an equivalent amount of funds.

	•	The requirement that Pride stockholder approval be obtained as a condition to consummation of the merger.

In the course of its deliberations, the Pride board of directors also considered a variety of risks and other potentially negative factors, including the following:


	•	That because the merger consideration is a fixed dollar amount and a fixed exchange ratio of Ensco ADSs to Pride common stock, Pride stockholders could be adversely affected by a decrease in the trading price of Ensco ADSs during the pendency of the merger and the fact that the merger agreement does not provide Pride with a price-based termination right or other similar protection.

	•	That Ensco’s obligation to close the merger is conditioned on a vote of its shareholders.

	•	That, while the merger is expected to be completed, there is no assurance that all conditions to the parties’ obligations to complete the merger will be satisfied or waived, and as a result, it is possible that the merger might not be completed even if approved by Pride’s stockholders and Ensco’s shareholders.

	•	The restrictions on the conduct of Pride’s business prior to completion of the merger, requiring Pride to conduct its business only in the ordinary course, subject to specific limitations, which may delay or prevent Pride from undertaking business opportunities that may arise pending completion of the merger.

	•	That the exchange of shares of Pride common stock for Ensco ADSs and cash generally will be a taxable transaction for U.S. federal income tax purposes.

	•	The limitations imposed on Pride’s ability to solicit alternative transactions prior to closing or termination of the merger agreement, including the requirement to pay a $260 million termination fee in the event Pride accepts a superior proposal.

	•	The transaction costs to be incurred in connection with the merger.

	•	Risks of the type and nature described under “Risk Factors.”

Pride’s board considered all of these factors as a whole and, on balance, concluded that they supported a determination to approve the merger agreement. The foregoing discussion of the information and factors considered by the Pride board of directors is not exhaustive. In view of the wide variety of factors considered

by the Pride board of directors in connection with its evaluation of the proposed transaction and the complexity of these matters, the Pride board of directors did not consider it practical to, nor did it attempt to, quantify, rank or otherwise assign relative weights to the specific factors that it considered in reaching its decision. The Pride board of directors evaluated the factors described above, among others, and reached a consensus that the proposed transaction was advisable, fair to and in the best interests of Pride and its stockholders. In considering the factors described above and any other factors, individual members of the Pride board of directors may have viewed factors differently or given different weight or merit to different factors.

In considering the recommendation of the Pride board of directors to adopt the merger agreement, Pride stockholders should be aware that the executive officers and directors of Pride have certain interests in the merger that may be different from, or in addition to, the interests of Pride stockholders generally. The Pride board of directors was aware of these interests and considered them when approving the merger agreement and recommending that Pride stockholders vote to adopt the merger agreement. See “— Interests of the Pride Directors and Executive Officers in the Merger.”

It should be noted that this explanation of the reasoning of the Pride board of directors and all other information presented in this section is forward-looking in nature and, therefore, should be read in light of the factors discussed under the heading “Cautionary Statement Concerning Forward-Looking Statements.”

Opinion of Deutsche Bank Securities Inc.

Deutsche Bank has acted as Ensco’s financial advisor in connection with the merger. At the February 5, 2011 meeting of the board of directors of Ensco, Deutsche Bank delivered its oral opinion, subsequently confirmed in writing on February 6, 2011, to the board of directors of Ensco to the effect that, as of the date of such opinion, and based upon and subject to the assumptions, limitations, qualifications and conditions described in Deutsche Bank’s opinion, the merger consideration comprised of $15.60 in cash and 0.4778 Ensco ADSs, each whole ADS representing one Class A ordinary share, to be paid in respect of each share of Pride common stock in the merger was fair, from a financial point of view, to Ensco.

The full text of Deutsche Bank’s written opinion, dated February 6, 2011, which sets forth, among other matters, the assumptions made, matters considered, and limitations, qualifications and conditions of the review undertaken by Deutsche Bank in connection with the opinion, is attached as Annex B to this proxy statement/prospectus and is incorporated herein by reference. The summary of the Deutsche Bank opinion set forth in this proxy statement/prospectus is qualified in its entirety by reference to the full text of the opinion. Deutsche Bank’s opinion was addressed to, and for the use and benefit of, the Ensco board of directors. The Deutsche Bank opinion is not a recommendation as to how any holder of Ensco ADSs or Ensco Class A ordinary shares should vote with respect to the merger. Deutsche Bank’s opinion is limited to the fairness, from a financial point of view, of the merger consideration to be paid in respect of each share of Pride common stock and does not address any other aspect of the merger. Deutsche Bank was not asked to, and Deutsche Bank’s opinion did not, address the fairness of the merger to the holders of any class of securities, creditors or other constituencies of Ensco. Deutsche Bank expressed no opinion as to the merits of the underlying decision by Ensco to engage in the merger or the relative merits of the merger as compared to any alternative transactions or business strategies. Nor did Deutsche Bank express an opinion as to how any holder of the Ensco ADSs or Class A ordinary shares should vote with respect to the merger. Deutsche Bank did not express any view or opinion as to the fairness, financial or otherwise, of the amount or nature of any compensation payable to or to be received by any of the officers, directors, or employees of any party to the merger, or any class of such persons, in connection with the merger relative to the merger consideration.

In connection with Deutsche Bank’s role as financial advisor to Ensco, and in arriving at its opinion, Deutsche Bank reviewed certain publicly available financial and other information concerning Ensco and Pride, and certain internal analyses, financial forecasts and other information relating to Ensco, Pride and the combined company prepared by the management of Ensco. Deutsche Bank also held discussions with certain senior officers and other representatives and advisors of Ensco and Pride regarding the businesses and

prospects of Ensco, Pride and the combined company, including certain cost savings and operating synergies projected by the management of Ensco to result from the merger. In addition, Deutsche Bank:


	•	reviewed the reported prices and trading activity for both the Ensco ADSs and Pride common stock;

	•	compared certain financial and stock market information for Ensco and Pride with, to the extent publicly available, similar information for certain other companies it considered relevant whose securities are publicly traded;

	•	to the extent publicly available, reviewed the financial terms of certain recent business combinations or acquisition transactions it deemed relevant;

	•	reviewed the merger agreement; and

	•	performed such other studies and analyses and considered such other factors as it deemed appropriate.

Deutsche Bank did not assume responsibility for independent verification of, and did not independently verify, any information, whether publicly available or furnished to it, concerning Ensco or Pride, including, without limitation, any financial information considered in connection with the rendering of its opinion. Accordingly, for purposes of its opinion, Deutsche Bank, with the knowledge and permission of the board of directors of Ensco, assumed and relied upon the accuracy and completeness of all such information. Deutsche Bank did not conduct a physical inspection of any of the properties or assets, and did not prepare or obtain any independent evaluation or appraisal of any of the assets or liabilities (including any contingent, derivative or off-balance-sheet assets or liabilities) of Ensco, Pride or any of their respective subsidiaries, nor did Deutsche Bank evaluate the solvency or fair value of Ensco, Pride or the combined company (or the impact of the merger thereon) under any law relating to bankruptcy, insolvency or similar matters. With respect to the financial forecasts, including, without limitation, the analyses and forecasts of the amount and timing of certain cost savings, operating efficiencies, revenue effects, financial synergies and other strategic benefits projected by management of Ensco to be achieved as a result of the merger (collectively, the “Synergies”), made available to Deutsche Bank and used in its analyses, Deutsche Bank assumed, with the knowledge and permission of the board of directors of Ensco, that the forecasts had been reasonably prepared on bases reflecting the best currently available estimates and judgments of the management of Ensco as to the matters covered thereby. In rendering its opinion, Deutsche Bank expressed no view as to the reasonableness of such forecasts and projections, including, without limitation, the Synergies, or the assumptions on which they were based. Deutsche Bank’s opinion was necessarily based upon economic, market and other conditions as in effect on, and the information made available to it as of, the date of the opinion. Deutsche Bank expressly disclaimed any undertaking or obligation to advise any person of any change in any fact or matter affecting its opinion of which it becomes aware after the date of its opinion.

For purposes of rendering its opinion, Deutsche Bank assumed, with the permission of the board of directors of Ensco, that in all respects material to its analysis, the merger would be consummated in accordance with the terms of the merger agreement, without any material waiver, modification or amendment of any term, condition or agreement. Deutsche Bank also assumed that all material governmental, regulatory or other approvals and consents required in connection with the consummation of the merger would be obtained and that in connection with obtaining any necessary governmental, regulatory or other approvals and consents, no restrictions, terms or conditions would be imposed that would be material to its analysis. Deutsche Bank is not a legal, regulatory, tax or accounting expert and Deutsche Bank relied on the assessments made by Ensco and its advisors with respect to such issues.

Deutsche Bank’s opinion was approved and authorized for issuance by a Deutsche Bank fairness opinion review committee and was addressed to, and for the use and benefit of, the board of directors of Ensco in connection with and for the purposes of its evaluation of the merger. Deutsche Bank’s opinion was limited to the fairness of the merger consideration to be paid in respect of each share of Pride common stock, from a financial point of view, to Ensco as of the date of the opinion. Deutsche Bank’s opinion did not address any other terms of the merger or the merger agreement. Deutsche Bank was not asked to, and its opinion did not, address the fairness of the merger, or any consideration received in connection therewith, to the holders of any class of securities, creditors or other constituencies of Ensco, nor did it address the fairness of the

contemplated benefits of the merger. Deutsche Bank expressed no opinion as to the merits of the underlying decision by Ensco to engage in the merger or the relative merits of the merger as compared to any alternative transactions or business strategies. Nor did Deutsche Bank express any opinion, and its opinion did not constitute a recommendation, as to how any holder of Ensco ADSs or Ensco Class A ordinary shares should vote with respect to the merger. In addition, Deutsche Bank did not express any view or opinion as to the fairness, financial or otherwise, of the amount or nature of any compensation payable to or to be received by any officers, directors, or employees of any parties to the merger agreement, or any class of such persons, in connection with the merger relative to the merger consideration. Deutsche Bank’s opinion did not in any manner address the prices at which the Ensco ADSs, Pride common stock or any other securities would trade following the announcement or consummation of the merger.

The following is a summary of the material financial analyses contained in the presentation that was made by Deutsche Bank to the board of directors of Ensco on February 5, 2011 and that were used by Deutsche Bank in connection with rendering its opinion described above. The following summary, however, does not purport to be a complete description of the financial analyses performed by Deutsche Bank, nor does the order in which the analyses are described represent the relative importance or weight given to the analyses by Deutsche Bank. Some of the summaries of the financial analyses include information presented in tabular format. The tables must be read together with the full text of each summary and are alone not a complete description of Deutsche Bank’s financial analyses. Except as otherwise noted, the following quantitative information, to the extent that it is based on market data, is based on market data as it existed on or before February 4, 2011, and is not necessarily indicative of current market conditions.

Implied Transaction Multiples Analysis

Based upon the closing price of $54.41 per Ensco ADS on February 4, 2011, Deutsche Bank calculated that the merger consideration, consisting of 0.4778 of an Ensco ADS and $15.60 in cash, had an implied value of $41.60 per share of Pride common stock. Deutsche Bank then derived an implied total enterprise value for Pride of approximately $8.89 billion by multiplying this implied value of the merger consideration by the number of fully diluted shares of Pride common stock outstanding and adding Pride’s estimated net debt as of December 31, 2010 of approximately $1.379 billion.

Using the results of the calculations described above and Wall Street consensus estimates for Pride, Deutsche Bank calculated the following premia and multiples:


	•	price as a premium to the closing price of Pride common stock on February 4, 2011;

	•	price as a premium to the volume weighted average price (which we refer to as “VWAP”) of Pride common stock during the one month and three months ended February 4, 2011, respectively; and

	•	total enterprise value (which we refer to as “TEV”) as a multiple of Wall Street consensus estimated earnings before interest, tax expense, depreciation and amortization (which we refer to as “EBITDA”) for 2010, 2011 and 2012, respectively.

The results of this analysis are summarized as follows:


Premium to
2/4/2011 Close	21.0	%
1-Month VWAP	25.4	%
3-Month VWAP	27.9	%
Implied Multiple of TEV to
2010E consensus EBITDA	18.5	x
2011E consensus EBITDA	10.6	x
2012E consensus EBITDA	8.7	x

Selected Trading Comparables Analysis — Pride

Deutsche Bank reviewed and compared certain financial information and commonly used valuation measurements for Pride with corresponding financial information and measurements for the following selected companies:


	•	Transocean Ltd.

	•	Seadrill Limited

	•	Noble Corporation

	•	Diamond Offshore Drilling, Inc.

	•	Fred Olsen Energy ASA

	•	Atwood Oceanics, Inc.

These companies were selected as comparables because they are publicly traded companies in the offshore drilling industry with rig fleets weighted towards floater rigs, which are similar to Pride’s fleet. Although none of the selected companies is directly comparable to Pride, the companies included were selected by Deutsche Bank based upon Deutsche Bank’s general experience and knowledge of offshore drilling companies that for purposes of this analysis may be considered similar to certain operations of Pride. Accordingly, the analysis of publicly traded comparable companies was not simply mathematical. Rather, it involved complex considerations and qualitative judgments, reflected in Deutsche Bank’s opinion, concerning differences in financial and operating characteristics of the selected companies and other factors that could affect the public trading value of such companies.

Based on the closing prices of Pride common stock and the common stock of the selected companies on February 4, 2011, information contained in the most recent public periodic and other filings of the selected companies and Wall Street consensus estimates of EBITDA for Pride and the selected companies, Deutsche Bank calculated the multiple of total enterprise value to estimated EBITDA for each of 2010, 2011 and 2012, respectively.

The results of this analysis are summarized as follows:


	Price		TEV		TEV/EBITDA
Company	at 2/4/2011		(millions)		2010E			2011E			2012E

Transocean Ltd.	$	79.99	$	33,925		7.4	x		7.1	x		7.0	x
Seadrill Limited	$	34.44	$	23,306		11.1	x		9.0	x		8.5	x
Noble Corporation	$	37.60	$	12,021		8.3	x		8.5	x		6.0	x
Diamond Offshore Drilling, Inc.	$	71.67	$	10,475		5.9	x		6.0	x		6.5	x
Fred Olsen Energy ASA	$	45.09	$	3,811		6.1	x		5.3	x		5.6	x
Atwood Oceanics, Inc.	$	40.80	$	2,713		7.7	x		7.1	x		6.5	x
Median of Selected Companies						7.6	x		7.1	x		6.5	x
Pride	$	34.39	$	7.573		15.7	x		9.0	x		7.4	x

Based in part on the trading multiples of the selected companies described above, Deutsche Bank calculated a range of the estimated total enterprise value of Pride by applying multiples of total enterprise value to estimated EBITDA ranging from 8.0x to 9.0x and 7.0x to 8.0x to Wall Street consensus estimates of Pride’s EBITDA for 2011 and 2012, respectively. Deutsche Bank then subtracted Pride’s estimated net debt as of December 31, 2010 of approximately $1.379 billion from the ranges of total enterprise value and divided the results by the number of fully diluted shares of Pride common stock outstanding to derive ranges of implied equity value per share of Pride common stock ranging from $29.66 to $34.27 based on Wall Street consensus EBITDA estimates for 2011, and from $32.06 to $37.65 based on Wall Street consensus EBITDA estimates for 2012.

Selected Precedent Transactions Analysis — Pride

Deutsche Bank reviewed publicly available information relating to certain selected acquisition transactions in the offshore drilling and oilfield service industries that were announced between 1997 and 2010.

The Offshore Drilling Industry transactions involved the acquisition of corporate entities comprised primarily of floating rigs and/or higher specification jackup rigs larger than $500 million. The Oilfield Service Industry transactions, which were utilized solely to compare premiums paid, were selected due to the similar characteristics these transactions had when compared to the transaction involving Pride including, but not limited to, transactions in the Oilfield Service Industry involving public targets larger than $500 million and a consideration mix including cash and stock. Transactions characterized as mergers of equals were excluded. Although none of the selected transactions is directly comparable to the Pride transaction, the transactions included were selected by Deutsche Bank based upon its general experience and knowledge of precedent transactions of a similar nature that for purposes of this analysis may be considered similar to the transaction involving Pride.

With respect to each selected transaction, Deutsche Bank calculated the value of the per share consideration paid in such transaction as a premium to the closing price of the target’s common stock on the last trading day prior to the announcement of the applicable transaction and to the price of the target’s common stock one-month prior to the announcement of the applicable transaction. With respect to each selected transaction in the offshore drilling industry, Deutsche Bank also calculated the target’s total enterprise value, or TEV, as a multiple of Wall Street consensus EBITDA estimates for the target for the first fiscal year

ended after announcement of the transaction, referred to as FY+1 EBITDA. The results of these analyses are summarized as follows:


			Target		Premium to
			TEV		Prior Close						TEV/
Date Announced	Acquirer	Target	(millions)		1-Day			1-Month			FY+1 EBITDA

Offshore Drilling Industry
06/27/2010	Noble Corporation	FDR Holdings Limited	$	2,160		—			—			11.3	x
07/07/2008	China Oilfield Services Ltd.	Awilco Offshore ASA	$	3,794		19	%		18	%		13.9	x
04/22/2008	DryShips Inc.	Ocean Rig ASA	$	1,331		29	%		25	%		15.7	x
01/02/2007	Aban Offshore Ltd.	Sinvest ASA	$	1,327		35	%		7	%		8.0	x
01/09/2006	Seadrill Limited	Smedvig ASA	$	3,021		22	%		52	%		12.7	x
05/15/2002	ENSCO International Incorporated	Chiles Offshore Inc.	$	674		14	%		24	%		18.0	x
08/21/2000	Transocean Sedco Forex Inc.	R&B Falcon Corporation	$	8,754		19	%		31	%		10.8	x
07/10/1997	Falcon Drilling Company, Inc.	Reading & Bates Corporation	$	2,805		17	%		26	%		11.9	x
Mean of Selected Offshore Drilling Industry Transactions				—		22	%		26	%		12.8	x
Median of Selected Offshore Drilling Industry Transactions				—		19	%		25	%		12.3	x
Oilfield Service Industry
12/13/2010	General Electric Company	Wellstream Holdings PLC	$	1,366		31	%		55	%		—
05/10/2010	Seadrill Limited	Scorpion Offshore Limited	$	1,242		14	%		25	%		—
02/19/2010	Schlumberger Limited	Smith International, Inc.	$	12,591		37	%		52	%		—
08/31/2009	Baker Hughes Incorporated	BJ Services Company	$	5,530		16	%		26	%		—
06/02/2009	Cameron International Corporation	NATCO Group Inc.	$	923		53	%		87	%		—
06/03/2008	Smith International, Inc.	W-H Energy Services, Inc.	$	3,203		20	%		31	%		—
05/23/2008	Umbrellastream Ltd	Expro International Group	$	3,820		74	%		73	%		—
		PLC
12/17/2007	National Oilwell Varco, Inc.	Grant Prideco, Inc.	$	7,238		22	%		23	%		—
03/19/2007	Hercules Offshore, Inc.	TODCO	$	2,172		28	%		28	%		—
02/12/2007	Tenaris S.A.	Hydril Company	$	2,017		17	%		40	%		—
Mean of Selected Oilfield Service Industry Transactions				—		31	%		44	%		—
Median of Selected Oilfield Service Industry Transactions				—		25	%		36	%		—
Mean of All Selected Transactions				—		27	%		37	%		—
Median of All Selected Transactions				—		22	%		28	%		—

With respect to the acquisitions of Ocean Rig ASA, Sinvest ASA, Smedvig ASA, Wellstream Holdings PLC, Scorpion Offshore Limited and Expro International Group PLC, the premia were calculated based upon the closing price of the target’s common stock on the last trading day as of which the price of the target’s common stock was assumed to be unaffected and one month prior to such date.

Based in part on the premia and multiples of the selected transactions described above, Deutsche Bank selected reference ranges of the same premia and multiples and derived corresponding ranges of estimated equity value per share of Pride common stock as follows:


	•	Deutsche Bank calculated a range of the implied total enterprise value of Pride by applying multiples of total enterprise value to EBITDA ranging from 10.0x to 12.0x to Wall Street consensus estimates of Pride’s EBITDA for 2011. Deutsche Bank then subtracted from the total enterprise values Pride’s estimated net debt as of December 31, 2010 of approximately $1.379 billion and divided the results by the number of fully diluted shares of Pride common stock outstanding. This analysis resulted in a range of implied equity value per share of Pride common stock of $38.85 to $48.03 per share.

	•	Deutsche Bank calculated a range of implied equity value per share of Pride common stock by applying premia ranging from 15% to 30% to the closing price of Pride common stock on February 4, 2011.


		This analysis resulted in a range of implied equity value per share of Pride common stock ranging from $39.55 to $44.71 per share.


	•	Deutsche Bank calculated a range of implied equity value per share of Pride common stock by applying premia ranging from 25% to 40% to the volume weighted average price of Pride common stock for the one-month period ended February 4, 2011. This analysis resulted in a range of implied equity value per share of Pride common stock of $41.48 to $46.46 per share.

Discounted Cash Flow Analysis

Deutsche Bank performed a discounted cash flow analysis to determine a range of implied net present values per share of Pride common stock. Deutsche Bank calculated the discounted cash flow value for Pride as the sum of the net present value of (i) the estimated future unlevered free cash flow, calculated as earnings before interest expense and taxes, less cash taxes, referred to as tax-adjusted EBIT, minus capital expenditures, plus or minus changes in working capital, and plus depreciation and amortization, that Pride will generate for the years 2011 through 2015, plus (ii) the value of Pride at the end of such period, or the terminal value, calculated by applying multiples of terminal value to last-twelve-month EBITDA ranging from 8.0x to 10.0x (selected by Deutsche Bank based on its analysis of historical comparable multiples of the selected companies described under “— Selected Trading Comparables Analysis — Pride” above) to estimates of Pride’s EBITDA in a terminal year which equated to 2015 prepared by management of Ensco assuming no net synergies. Based on its calculation of Pride’s estimated weighted average cost of capital, Deutsche Bank applied discount rates ranging from 9.0% to 11.0% to Pride’s future cash flows and terminal value to derive a range of present total enterprise values for Pride. Deutsche Bank subtracted Pride’s estimated net debt as of December 31, 2010 of approximately $1.379 billion from such present total enterprise values and divided the results by the number of fully diluted shares of Pride common stock outstanding. This analysis resulted in a range of implied net present value per share of Pride common stock of approximately $30.98 to $42.86 per share.

Using the same multiples and discount rates described above, Deutsche Bank performed similar discounted cash flow analyses assuming net pre-tax synergies of approximately $50 million per year starting in 2012 and approximately $25 million in costs in 2012 to achieve such synergies. This analysis resulted in a range of implied net present value of approximately $32.89 to $45.28 per share of Pride common stock.

Selected Trading Comparables Analysis — Ensco

Deutsche Bank reviewed and compared certain financial information and commonly used valuation measurements for Ensco with corresponding financial information and measurements for the following selected companies in the offshore drilling industry with a fleet concentrated in jackup rigs and floater rigs, respectively:

Selected Jackup Companies:


	•	Rowan Companies, Inc.

	•	Vantage Drilling Company

	•	Hercules Offshore, Inc.

Selected Floater Companies:


	•	Transocean Ltd.

	•	Seadrill Limited

	•	Noble Corporation

	•	Diamond Offshore Drilling, Inc.

	•	Pride International, Inc.


	•	Fred Olsen Energy ASA

	•	Atwood Oceanics, Inc.

These companies were selected as comparables because, similar to Ensco, they are publicly traded companies in the offshore drilling industry with rig fleets characterized predominantly as comprising jackup rigs and floater rigs, respectively. Ensco’s fleet comprises a balance of both jackup rigs and floater rigs, with a more significant concentration of jackup rigs. Although none of the selected companies is directly comparable to Ensco, the companies included were selected by Deutsche Bank based upon its general experience and knowledge of offshore drilling companies that for purposes of this analysis may be considered similar to certain operations of Ensco. Accordingly, the analysis of publicly traded comparable companies was not simply mathematical. Rather, it involved complex considerations and qualitative judgments, reflected in Deutsche Bank’s opinion, concerning differences in financial and operating characteristics of the selected companies and other factors that could affect the public trading value of such companies.

Based on the closing prices of the Ensco ADSs and the common stock of the selected companies on February 4, 2011, information contained in the most recent public periodic and other filings of the selected companies and Wall Street consensus estimates of EBITDA for Ensco and the selected companies, Deutsche Bank calculated the multiple of total enterprise value to estimated EBITDA for each of 2010, 2011 and 2012, respectively.

The results of this analysis are summarized as follows:


	Price at				TEV/EBITDA
Company	2/4/2011		TEV		2010E			2011E			2012E
			(millions)

Selected Jackup Companies:
Rowan Companies, Inc.	$	36.58	$	5,440		9.0	x		8.5	x		6.2	x
Vantage Drilling Company	$	1.90	$	1,608		18.4	x		6.7	x		6.1	x
Hercules Offshore, Inc.	$	3.49	$	1,125		7.0	x		7.3	x		8.1	x
Median of Selected Jackup Companies						9.0	x		7.3	x		6.2	x
Selected Floater Companies:
Transocean Ltd.	$	79.99	$	33,925		7.4	x		7.1	x		7.0	x
Seadrill Limited	$	34.44	$	23,306		11.1	x		9.0	x		8.5	x
Noble Corporation	$	37.60	$	12,021		8.3	x		8.5	x		6.0	x
Diamond Offshore Drilling, Inc.	$	71.67	$	10,475		5.9	x		6.0	x		6.5	x
Pride International, Inc.	$	34.39	$	7,573		15.7	x		9.0	x		7.4	x
Fred Olsen Energy ASA	$	45.09	$	3,811		6.1	x		5.3	x		5.6	x
Atwood Oceanics, Inc.	$	40.80	$	2,713		7.7	x		7.1	x		6.5	x
Median of Selected Floater Companies						7.7	x		7.1	x		6.5	x
Ensco	$	54.41	$	7.003		8.6	x		7.7	x		6.1	x

Based in part on the trading multiples of the selected companies described above, Deutsche Bank calculated a range of the estimated total enterprise value of Ensco by applying multiples of total enterprise value to estimated EBITDA ranging from 7.0x to 8.0x and 5.5x to 6.5x to the Wall Street consensus estimates of Ensco’s EBITDA for 2011 and 2012, respectively. Deutsche Bank then subtracted from the ranges of total enterprise value Ensco’s estimated net debt and minority interest of approximately ($787) million as of December 31, 2010 (i.e., adding Ensco’s net cash position) and divided the results by the number of fully diluted Ensco ADSs outstanding. This analysis resulted in ranges of implied equity value per Ensco ADS of $50.25 to $56.60 based on Wall Street consensus EBITDA estimates for 2011, and from $49.70 to $57.68 based on Wall Street consensus EBITDA estimates for 2012.

Pro Forma Transaction Analysis

Deutsche Bank performed an illustrative pro forma transaction analysis of the potential financial impact of the merger on Ensco using the implied value of the per share merger consideration of $41.60 and earnings and cash flow estimates for Ensco and Pride for 2011 and 2012 prepared by the management of Ensco. For purposes of this analysis, Deutsche Bank assumed the merger closed on December 31, 2010. This analysis incorporated assumptions made by Ensco’s management, including, among others, pre-tax synergies of $50 million in 2012 (excluding the effect of approximately $25 million in costs in 2012 to achieve such synergies), and the post-tax effect of (1) net incremental non-cash income of $54 million in 2011 and expense of $24 million in 2012 resulting from the mark-to-market impact of Pride’s drilling contracts, (2) incremental net interest expense associated with financing of $39 million in 2011 and $75 million in 2012, and (3) incremental depreciation expense of $14 million in each of 2011 and 2012, respectively.

This analysis indicated that the merger would be accretive to Ensco on an earnings per share basis and on a cash flow per share basis for both years analyzed. The following table summarizes the results of this analysis:

Illustrative Accretion Statistics


	Accretion

Earnings Per Share
2011E		18	%
2012E		11	%
Cash Flow Per Share
2011E		9	%
2012E		12	%

In addition, Deutsche Bank noted that at the implied offer price of $41.60 per share of Pride common stock, the pro forma ratios of net debt to estimated EBITDA for Ensco after giving effect to the merger were 3.1x, 2.6x and 1.9x for 2010, 2011 and 2012, respectively, compared to a standalone case of (1.0x), (1.1x) and (0.9x) for 2010, 2011 and 2012, respectively.

The preparation of a fairness opinion is a complex process involving the application of subjective business and financial judgment in determining the most appropriate and relevant methods of financial analysis and the application of those methods to the particular circumstances and, therefore, is not readily susceptible to summary description. Deutsche Bank believes that its analyses must be considered as a whole and that considering any portion of such analyses and of the factors considered without considering all analyses and factors could create a misleading view of the process underlying the opinion. In arriving at its fairness determination, Deutsche Bank did not assign specific weights to any particular analyses.

In conducting its analyses and arriving at its opinion, Deutsche Bank utilized a variety of generally accepted valuation methods. The analyses were prepared solely for the purpose of enabling Deutsche Bank to provide its opinion to the board of directors of Ensco as to the fairness, from a financial point of view, of the merger consideration to be paid in respect of each share of Pride common stock to Ensco described above as of the date of its opinion and do not purport to be appraisals or necessarily reflect the prices at which businesses or securities actually may be sold, which are inherently subject to uncertainty. As described above, in connection with its analyses, Deutsche Bank made, and was provided by the management of Ensco with, numerous assumptions with respect to industry performance, general business and economic conditions and other matters, many of which are beyond the control of Deutsche Bank, Pride or Ensco. Analyses based on estimates or forecasts of future results are not necessarily indicative of actual past or future values or results, which may be significantly more or less favorable than suggested by such analyses. Because such analyses are inherently subject to uncertainty, being based upon numerous factors or events beyond the control of Ensco, Pride or their respective advisors, future results or actual values may be materially different from these forecasts or assumptions.

The terms of the transaction, including the merger consideration, were determined through arm’s-length negotiations between Ensco and Pride and were approved by the board of directors of Ensco. Although Deutsche Bank provided advice to the Ensco board of directors during the course of these negotiations, the decision to enter into the merger was solely that of the Ensco board of directors. As described above under “— Recommendations of the Ensco Board of Directors and Its Reasons for the Merger,” the opinion and presentation of Deutsche Bank to the board of directors of Ensco were only one of a number of factors taken into consideration by the board of directors of Ensco in making its determination to approve the merger agreement and the transactions contemplated by it, including the merger.

Ensco selected Deutsche Bank as its financial advisor in connection with the transaction based on Deutsche Bank’s qualifications, expertise, reputation and experience in mergers and acquisitions. Ensco has retained Deutsche Bank pursuant to a letter agreement dated December 22, 2010. As compensation for Deutsche Bank’s services in connection with the merger, Ensco has agreed to pay Deutsche Bank a fee of $15 million, of which $3.75 million became payable upon delivery of Deutsche Bank’s opinion (or would have become payable upon Deutsche Bank advising Ensco that it was unable to render an opinion) and the remainder is contingent upon consummation of the merger. Ensco may also pay Deutsche Bank an additional discretionary fee of up to $5 million, determined in Ensco’s sole discretion, to compensate Deutsche Bank based on the complexity of the transaction. Regardless of whether the transaction is consummated, Ensco has agreed to reimburse Deutsche Bank for reasonable fees and disbursements of Deutsche Bank’s counsel and all of Deutsche Bank’s reasonable travel and other out-of-pocket expenses incurred in connection with the transaction or otherwise arising out of the retention of Deutsche Bank under the engagement letter. Ensco has also agreed to indemnify Deutsche Bank and certain related persons to the fullest extent lawful against certain liabilities, including certain liabilities under the federal securities laws arising out of its engagement or the transaction.

Deutsche Bank is an internationally recognized investment banking firm experienced in providing advice in connection with mergers and acquisitions and related transactions. Deutsche Bank is an affiliate of Deutsche Bank AG, which, together with its affiliates, is referred to as the DB Group. One or more members of the DB Group have, from time to time, provided, and are currently providing, investment banking, commercial banking (including extension of credit) and other financial services to Ensco or its affiliates for which they have received, and in the future may receive, compensation, including acting as a lender under Ensco’s $700,000,000 revolving credit facility since May 2010 (aggregate commitment $40,000,000). During the two year period ended February 6, 2011, the DB Group has received revenues for services provided to Ensco and its affiliates unrelated to the transaction of approximately $0.2 million. One or more members of the DB Group have, from time to time, provided investment banking, commercial banking (including extension of credit) and other financial services to Pride or its affiliates for which it has received compensation but the DB Group has not provided any such services to Pride or its affiliates in the last two years. The DB Group may also provide investment and commercial banking services to Ensco, Pride and their respective affiliates in the future, for which the DB Group would expect to receive compensation. In addition, at the time of the execution of the merger agreement, one or more members of the DB Group had agreed to provide financing to Ensco in connection with the merger. Following the execution of the merger agreement, Deutsche Bank acted as joint book-running manager in connection with Ensco’s issuance of $1.0 billion aggregate principal amount of 3.25% senior notes due 2016 and $1.5 billion aggregate principal amount of 4.70% senior notes due 2021 on March 17, 2011. In connection with the issuance of the senior notes, Deutsche Bank received underwriting discounts and commissions in the aggregate amount of approximately $4.7 million. Due to the issuance of the senior notes and the availability of cash on hand, Ensco terminated the bridge commitment letter pursuant to which members of the DB Group would have provided such financing to Ensco. In the ordinary course of business, members of the DB Group may actively trade in the securities and other instruments and obligations of Ensco, Pride or their respective affiliates for their own accounts and for the accounts of their customers. Accordingly, the DB Group may at any time hold a long or short position in such securities, instruments and obligations.

Opinion of Goldman, Sachs & Co.

At the meeting of the board of directors of Pride on February 6, 2011, Goldman Sachs delivered its oral opinion, subsequently confirmed in writing, that, as of February 6, 2011, and based upon and subject to the limitations and assumptions set forth therein, the per share consideration of $15.60 in cash and 0.4778 Ensco ADSs, each duly and validly issued against the deposit of an equal number of Ensco Class A ordinary shares, to be paid to the holders (other than Ensco and its affiliates) of the outstanding shares of Pride common stock pursuant to the merger agreement (which for purposes of this section refers to the original merger agreement dated February 6, 2011) was fair from a financial point of view to such holders.

The full text of the written opinion of Goldman Sachs, dated February 6, 2011, which sets forth assumptions made, procedures followed, matters considered and limitations on the review undertaken in connection with the opinion, is attached as Annex C to this joint proxy statement/prospectus. Goldman Sachs provided its advisory services and its opinion for the information and assistance of the board of directors of Pride in connection with its consideration of the merger. The Goldman Sachs opinion does not constitute a recommendation as to how any holder of Pride common stock should vote with respect to the merger or any other matter.

In connection with rendering the opinion described above and performing its related financial analyses, Goldman Sachs reviewed, among other things:


	•	the merger agreement;

	•	annual reports to stockholders and Annual Reports on Form 10-K of Pride and Ensco for the five years ended December 31, 2009;

	•	certain interim reports to stockholders and Quarterly Reports on Form 10-Q of Pride and Ensco;

	•	certain other communications from Pride and Ensco to their respective stockholders;

	•	certain publicly available research analyst reports for Pride and Ensco;

	•	certain internal financial analyses and forecasts for Ensco prepared by its management;

	•	certain internal financial analyses and forecasts for Pride prepared by its management and certain financial analyses and forecasts for Ensco prepared by the management of Pride, including the Base Case Forecasts for each of Pride and Ensco (the “Base Case Forecasts”), in each case, as approved for Goldman Sachs’ use by Pride; and

	•	certain cost savings and operating synergies projected by the management of Pride to result from the merger, as approved for Goldman Sachs’ use by Pride (the “Synergies”).

Goldman Sachs also held discussions with members of the senior managements of Pride and Ensco regarding their assessment of the strategic rationale for, and the potential benefits of, the merger and the past and current business operations, financial condition and future prospects of Pride and Ensco. In addition, Goldman Sachs reviewed the reported price and trading activity for the Pride common stock, Ensco Class A ordinary shares and Ensco ADSs; compared certain financial and stock market information for Pride and Ensco with similar information for certain other companies the securities of which are publicly traded; reviewed the financial terms of certain recent business combinations in the offshore drilling industry and in other industries; and performed such other studies and analyses, and considered such other factors, as Goldman Sachs deemed appropriate.

For purposes of rendering the opinion described above, Goldman Sachs relied upon and assumed, without assuming any responsibility for independent verification, the accuracy and completeness of all of the financial, legal, regulatory, tax, accounting and other information provided to, discussed with or reviewed by, Goldman Sachs; and Goldman Sachs did not assume any responsibility for any such information. In that regard, Goldman Sachs assumed with the consent of the board of directors of Pride that the Base Case Forecasts and the Synergies were reasonably prepared on a basis reflecting the best currently available estimates and judgments of the management of Pride. In addition, Goldman Sachs did not make an independent evaluation or appraisal of the assets and liabilities (including any contingent, derivative or other off-balance-sheet assets and liabilities) of Pride or Ensco or any of their respective subsidiaries nor was any such evaluation or

appraisal furnished to Goldman Sachs. Goldman Sachs assumed that all governmental, regulatory or other consents and approvals necessary for the consummation of the merger will be obtained without any adverse effect on Pride or Ensco or on the expected benefits of the merger in any way meaningful to Goldman Sachs’ analysis. Goldman Sachs also assumed that the merger will be consummated on the terms set forth in the merger agreement, without the waiver or modification of any term or condition the effect of which would be in any way meaningful to Goldman Sachs’ analysis.

Goldman Sachs’ opinion does not address the underlying business decision of Pride to engage in the merger, or the relative merits of the merger as compared to any strategic alternatives that may be available to Pride; nor does it address any legal, regulatory, tax or accounting matters. Goldman Sachs’ opinion addresses only the fairness from a financial point of view, as of the date of its opinion, of the consideration to be paid to the holders (other than Ensco and its affiliates) of Pride common stock pursuant to the merger agreement. Goldman Sachs does not express any view on, and its opinion does not address, any other term or aspect of the merger agreement or merger or any term or aspect of any other agreement or instrument contemplated by the merger agreement or entered into or amended in connection with the merger, including, without limitation, the fairness of the merger to, or any consideration received in connection therewith by, the holders of any other class of securities, creditors, or other constituencies of Pride; nor as to the fairness of the amount or nature of any compensation to be paid or payable to any of the officers, directors or employees of Pride, or class of such persons, in connection with the merger, whether relative to the consideration to be paid to the holders (other than Ensco and its affiliates) of Pride common stock pursuant to the merger agreement or otherwise. Goldman Sachs expressed no opinion as to the prices at which Ensco Class A ordinary shares or Ensco ADSs will trade at any time or as to the impact of the merger on the solvency or viability of Pride or Ensco or the ability of Pride or Ensco to pay their respective obligations when they come due. Goldman Sachs’ opinion is necessarily based on economic, monetary, market and other conditions as in effect on, and the information made available to Goldman Sachs as of, the date of its opinion and Goldman Sachs assumes no responsibility for updating, revising or reaffirming its opinion based on circumstances, developments or events occurring after such date.

Summary of Financial Analyses of Pride’s Financial Advisor

The following is a summary of the material financial analyses delivered by Goldman Sachs to the board of directors of Pride in connection with rendering the opinion described above. The following summary, however, does not purport to be a complete description of the financial analyses performed by Goldman Sachs, nor does the order of analyses described represent relative importance or weight given to those analyses by Goldman Sachs. Some of the summaries of the financial analyses include information presented in tabular format. The tables must be read together with the full text of each summary and are alone not a complete description of Goldman Sachs’ financial analyses. Except as otherwise noted, the following quantitative information, to the extent that it is based on market data, is based on market data as it existed on or before February 6, 2011, and is not necessarily indicative of current market conditions.

Selected Companies Analysis. Goldman Sachs reviewed and compared certain financial information for Pride and Ensco to corresponding financial information, ratios and public market multiples for the following publicly traded corporations in the offshore drilling industry:

Atwood Oceanics, Inc.

Diamond Offshore Drilling, Inc.

Noble Corporation

Rowan Companies, Inc.

Seadrill Limited

Transocean Ltd.

Each of these companies is referred to as a “Selected Company.”

Although none of the Selected Companies is directly comparable to Pride or Ensco, the companies included were chosen because each is an offshore drilling company, with its common stock listed on a United States securities exchange and with a market capitalization of at least $2 billion.

Goldman Sachs calculated and compared various financial multiples and ratios for the Selected Companies, Pride and Ensco. The financial multiples and ratios for the Selected Companies were based on closing stock market prices on February 4, 2011, information obtained from public filings and estimates from the Institutional Brokers Estimate System, or IBES. The financial multiples and ratios for Ensco were based on closing stock market prices on February 4, 2011, information obtained from public filings, IBES estimates and the Base Case Forecasts. The financial multiples and ratios for Pride were based on closing stock market prices on February 4, 2011, the $41.60 implied value per share of Pride common stock to be received by the holders of such shares in the merger (calculated based on the closing market price of Ensco ADSs on February 4, 2011), information obtained from public filings, IBES estimates and the Base Case Forecasts. The financial multiples and ratios include:


	•	ratios of enterprise value (computed as market capitalization plus outstanding debt as of September 30, 2010 minus cash and cash equivalents as of September 30, 2010) to each of estimated calendar year 2011 and 2012 earnings before interest, taxes, depreciation and amortization ( “EBITDA”);

	•	ratios of the share price to each of estimated calendar year 2011 and 2012 earnings per share; and

	•	ratios of the share price to each of estimated calendar year 2011 and 2012 cash flow per share.

Implied Multiples

Enterprise

Share Price/

Share Price/Cash

Value/EBITDA

Earnings Per Share

Flow Per Share

2011E

2012E

2011E

2012E

2011E

2012E

Company

Pride

8.9x

7.4x

12.8x

10.7x

8.4x

7.1x

(February 4, 2011 — IBES)

Pride

8.5x

7.5x

11.9x

10.7x

8.2x

7.4x

(February 4, 2011 — Base Case Forecasts)

Pride

10.5x

8.7x

15.5x

13.0x

10.2x

8.6x

(Merger Consideration — IBES)

Pride

10.0x

8.9x

14.4x

13.0x

10.0x

9.0x

(Merger Consideration — Base Case Forecasts)

Ensco

Ensco (IBES)

7.6x

6.2x

13.7x

10.6x

9.1x

7.5x

Ensco (Base Case)

9.4x

6.8x

18.2x

12.0x

11.7x

8.3x

Selected Companies

Atwood Oceanics, Inc. (IBES)

7.2x

6.8x

10.2x

8.5x

8.0x

Diamond Offshore Drilling, Inc. (IBES)

6.0x

6.4x

11.4x

12.5x

7.6x

7.9x

Noble Corporation (IBES)

8.8x

6.0x

17.1x

9.4x

7.5x

5.5x

Rowan Companies, Inc. (IBES)

8.3x

5.9x

16.6x

11.1x

9.4x

6.7x

Seadrill Limited (IBES)

9.4x

8.9x

10.7x

9.6x

7.7x

7.5x

Transocean Ltd. (IBES)

6.9x

6.7x

12.0x

11.3x

6.5x

6.2x

High

9.4x

8.9x

17.1x

12.5x

9.4x

8.0x

Low

6.0x

5.9x

10.2x

9.4x

6.5x

5.5x

Historical Exchange Ratio Analysis. Goldman Sachs calculated the average historical exchange ratios of Pride common stock to Ensco ADSs based on the closing prices of Pride common stock and Ensco ADSs during the 30-trading day, 60-trading day, 90-trading day, one-year, three-year and five-year periods ended February 4, 2011, as well as the exchange ratio of the closing prices of Pride common stock to Ensco ADSs on February 4, 2011. The following table presents the results of this analysis:

Average Exchange Ratio


	Implied Exchange Ratio
	of Pride common stock
	to Ensco ADSs

Time Period (up to February 4, 2011)
February 4, 2011		0.63x
30-day Average		0.62x
60-day Average		0.63x
90-day Average		0.64x
1-year Average		0.64x
3-year Average		0.61x
5-year Average		0.60x

Implied Present Value of Future Share Price Analysis. Goldman Sachs performed an illustrative analysis of the implied present value of the future price per share of Pride common stock, which is designed to provide an indication of the present value of a theoretical future value of a company’s equity as a function of such company’s estimated future EBITDA, its assumed enterprise value to forward year EBITDA multiple and its estimated future net debt amount. For this analysis, Goldman Sachs used the Base Case Forecasts. Goldman Sachs first calculated the implied values per share of Pride common stock for each of the years ended December 31, 2013, December 31, 2014 and December 31, 2015, by applying estimates of forward year EBITDA to assumed enterprise value to forward year EBITDA multiples of 4.0x to 12.0x, then subtracting the net debt as of year-end. The enterprise value to forward year EBITDA multiple range used by Goldman Sachs in this analysis was derived by Goldman Sachs utilizing its experience and professional judgment, taking into account current and historical trading data and the current and historical enterprise value to forward year EBITDA multiples for Pride and the Selected Companies referenced in “— Opinion of Goldman, Sachs & Co. — Summary of Financial Analyses of Pride’s Financial Advisor — Selected Companies Analysis” above. The implied per share future values of Pride common stock for each year were then discounted back to the beginning of 2011, using a range of illustrative discount rates from 11.0% to 15.0%, derived by utilizing the capital asset pricing model, which takes into account certain financial metrics, including beta, for Pride, as well as certain financial metrics for the United States financial markets generally. The analysis resulted in a range of implied present values per share of Pride common stock of $11.92 to $49.79, $13.26 to $49.65 and $13.12 to $45.55, for 2013, 2014 and 2015, respectively.

Relative Discounted Cash Flow Analysis. Goldman Sachs performed an illustrative relative discounted cash flow analysis to determine the implied exchange ratio of Pride common stock to Ensco ADSs, assuming each company continued to operate as a standalone company, using the Base Case Forecasts for Pride and Ensco.

In its analysis Goldman Sachs applied a range of illustrative discount rates for each of Pride and Ensco ranging from 9% to 13%, derived by utilizing the capital asset pricing model, which takes into account certain financial metrics, including betas, for Pride and Ensco, as well as certain financial metrics for the United States financial markets generally, to the projected cash flows (beginning January 1, 2011 and discounted using the mid-year convention) generated by Pride’s and Ensco’s assets over their estimated remaining lives. This analysis resulted in a range of implied exchange ratios of 0.46x to 0.51x.

Goldman Sachs also performed the same analysis as in the paragraph above based upon the same assumptions, except that in this analysis Goldman Sachs applied a range of discount rates for Pride ranging from 9% to 13% and applied a range of discount rates for Ensco equal to 100 basis points higher than the corresponding discount rate for Pride. This analysis resulted in a range of implied exchange ratios of 0.49x to 0.56x.

Goldman Sachs also calculated implied exchange ratios of Pride common stock to Ensco ADSs using present values of estimated cash flows for Pride and Ensco through the year 2015 and present values of an illustrative terminal value of Pride and Ensco at the end of year 2015, based on a range of multiples for Ensco of 3.0x to 11.0x estimated 2016 EBITDA and a range of multiples for Pride of the corresponding multiple for Ensco plus 0.0x to 2.0x, assuming an illustrative discount rate of 11%. The enterprise value to forward year EBITDA multiple range used by Goldman Sachs in this analysis was derived by Goldman Sachs utilizing its experience and professional judgment, taking into account current and historical trading data and the current and historical enterprise value to forward year EBITDA multiples for Pride, Ensco and the Selected Companies referenced in “— Opinion of Goldman, Sachs & Co. — Summary of Financial Analyses of Pride’s Financial Advisor — Selected Companies Analysis” above. This analysis resulted in a range of implied exchange ratios of 0.36x to 0.62x.

Goldman Sachs also calculated implied exchange ratios of Pride common stock to Ensco ADSs using present values of estimated cash flows for Pride and Ensco through the year 2015 and present values of an illustrative terminal value of Pride and Ensco at the end of year 2015, based on a range of multiples for Ensco of 3.0x to 11.0x estimated 2016 EBITDA and a range of multiples for Pride of the corresponding multiple for Ensco plus 0.0x to 2.0x, assuming an illustrative discount rate of 11% for Pride and an illustrative discount rate of 12% for Ensco. The enterprise value to forward year EBITDA multiple range used by Goldman Sachs in this analysis was derived by Goldman Sachs utilizing its experience and professional judgment, taking into account current and historical trading data and the current and historical enterprise value to forward year EBITDA multiples for Pride, Ensco and the Selected Companies referenced in “— Opinion of Goldman, Sachs & Co. — Summary of Financial Analyses of Pride’s Financial Advisor — Selected Companies Analysis” above. This analysis resulted in a range of implied exchange ratios of 0.37x to 0.64x.

Consideration vs. Standalone Discounted Cash Flow Analysis. Based on the Base Case Forecasts and Synergies, Goldman Sachs performed illustrative premium / (discount) analyses of the aggregate of an illustrative discounted cash flow value of the Ensco ADSs and cash to be received by holders of Pride common stock in the merger in relation to an illustrative standalone discounted cash flow analysis per share of Pride common stock to determine an implied premium or discount to the holders of Pride common stock as a result of the merger.

Goldman Sachs calculated ratios of the illustrative discounted cash flow value of the consideration to be paid to holders of Pride common stock in the merger to the illustrative standalone discounted cash flow analysis per share of Pride common stock, as of January 1, 2011, based on discount rates ranging from 9.0% to 13.0% applied to the estimated cash flows generated by Pride’s and Ensco’s assets over their estimated remaining lives. This analysis resulted in a range of premium/(discount) to standalone discounted cash flows of 28% to 51%.

Goldman Sachs then calculated ratios of the illustrative discounted cash flow value of the merger consideration to be paid to the holders of Pride common stock in the merger to the illustrative standalone discounted cash flow analysis per share of Pride common stock, as of January 1, 2011, using present values of estimated cash flows for Pride and Ensco through the year 2015 and present values of an illustrative terminal value of Pride and Ensco at the end of year 2015, based on a range of multiples for Pride of 4.0x to 12.0x estimated 2016 EBITDA and a range of multiples for Ensco of the corresponding multiple for Pride minus 1.5x to plus 0.5x, assuming a discount rate of 11%. The enterprise value to forward year EBITDA multiple range used by Goldman Sachs in this analysis was derived by Goldman Sachs utilizing its experience and professional judgment, taking into account current and historical trading data and the current and historical enterprise value to forward year EBITDA multiples for Pride, Ensco and the Selected Companies referenced in “— Opinion of Goldman, Sachs & Co. — Summary of Financial Analyses of Pride’s Financial Advisor — Selected Companies Analysis” above. This analysis resulted in a range of premium/(discount) to standalone discounted cash flows of 12% to 92%.

Accretion/Dilution Analysis. Goldman Sachs analyzed the pro forma financial effects of the merger using the Base Case Forecasts, IBES estimates and the Synergies. This analysis incorporated assumptions made by Pride’s management, including, among others, pre-tax synergies of $24 million and $98 million in 2011 and 2012, respectively, and the post-tax effect of net incremental non-cash expenses of $159 million and $80 million in 2011 and 2012, respectively, resulting from the mark-to-market impact of Pride’s drilling contracts, and incremental depreciation expense of $105 million in each of 2011 and 2012, respectively. Goldman Sachs compared the projected earnings per share and cash flow per share of Ensco on a standalone

basis for 2011 and 2012 to the projected earnings per share and cash flow per share of the combined company assuming completion of the merger. This analysis indicated that the merger would be dilutive to holders of Ensco ADSs on an estimated earnings per share basis for both years analyzed and accretive on an estimated cash flow per share basis for both years analyzed. The following table summarizes the results of this analysis:

Illustrative Accretion / Dilution Statistics


				Base Case
	IBES			Forecasts

Earnings Per Share
2011E		(26.6	)%		(16.9	)%
2012E		(8.9	)%		(5.1	)%
Cash Flow Per Share
2011E		7.3	%		22.1	%
2012E		11.3	%		14.2	%

The preparation of a fairness opinion is a complex process and is not necessarily susceptible to partial analysis or summary description. Selecting portions of the analyses or of the summary set forth above, without considering the analyses as a whole, could create an incomplete view of the processes underlying Goldman Sachs’ opinion. In arriving at its fairness determination, Goldman Sachs considered the results of all of its analyses and did not attribute any particular weight to any factor or analysis considered by it. Rather, Goldman Sachs made its determination as to fairness on the basis of its experience and professional judgment after considering the results of all of its analyses. No company or transaction used in the above analyses as a comparison is directly comparable to Pride or the merger.

Goldman Sachs prepared these analyses for purposes of Goldman Sachs’ providing its opinion to Pride’s board of directors as to the fairness from a financial point of view of the consideration to be received by the holders (other than Ensco and its affiliates) of outstanding Pride common stock in connection with the merger. These analyses do not purport to be appraisals nor do they necessarily reflect the prices at which businesses or securities actually may be sold. Analyses based upon forecasts of future results are not necessarily indicative of actual future results, which may be significantly more or less favorable than suggested by these analyses. Because these analyses are inherently subject to uncertainty, being based upon numerous factors or events beyond the control of the parties or their respective advisors, future results may be materially different from those forecast.

The merger consideration to be received by holders of Pride common stock was determined through arms’ length negotiations between Pride and Ensco and was approved by Pride’s board of directors. Goldman Sachs provided advice to Pride during these negotiations. Goldman Sachs did not, however, recommend any specific amount of consideration to Pride or its board of directors or that any specific amount of consideration constituted the only appropriate consideration for the merger.

As described above, Goldman Sachs’ opinion to Pride’s board of directors was one of many factors taken into consideration by Pride’s board of directors in making its determination to approve the merger agreement. The foregoing summary does not purport to be a complete description of the analyses performed by Goldman Sachs in connection with the fairness opinion and is qualified in its entirety by reference to the written opinion of Goldman Sachs attached as Annex C.

Goldman Sachs and its affiliates are engaged in investment banking and financial advisory services, commercial banking, securities trading, investment management, principal investment, financial planning, benefits counseling, risk management, hedging, financing, brokerage activities and other financial and non-financial activities and services for various persons and entities. In the ordinary course of these activities and services, Goldman Sachs and its affiliates may at any time make or hold long or short positions and investments, as well as actively trade or effect transactions, in the equity, debt and other securities (or related derivative securities) and financial instruments (including bank loans and other obligations) of Pride, Ensco,

any of their respective affiliates and third parties or any currency or commodity that may be involved in the merger contemplated by the merger agreement for their own account and for the accounts of their customers.

In addition, Goldman Sachs has provided certain investment banking services to Pride and its affiliates from time to time for which Goldman Sachs’ Investment Banking Division has received, and may receive, compensation, including having acted as bookrunner with respect to the public offering of Pride’s 8.5% Senior Notes due June 2019 (aggregate principal amount $500,000,000) in May 2009, financial advisor to Pride with respect to the spin-off of Seahawk Drilling in August 2009 and bookrunner with respect to the public offering of Pride’s 6.875% Senior Notes due June 2020 and 7.875% Senior Notes due 2040 (aggregate principal amount $1,200,000,000) in August 2010. During the two year period ended February 6, 2011, the Investment Banking Division of Goldman Sachs has accrued revenues for services provided to Pride and its affiliates unrelated to the transaction of approximately $16 million. Goldman Sachs also has provided certain investment banking services to Ensco and its affiliates from time to time for which Goldman Sachs’ Investment Banking Division has received, and may receive, compensation, including having acted as advisor to Ensco with respect to the attempted acquisition of Scorpion Offshore Limited in May 2010. During the two year period ended February 6, 2011, the Investment Banking Division of Goldman Sachs has accrued revenues for services provided to Ensco of approximately $3 million. Goldman Sachs may also in the future provide investment banking services to Pride, Ensco and their respective affiliates for which Goldman Sachs’ Investment Banking Division may receive compensation.

The board of directors of Pride selected Goldman Sachs as its financial advisor because it is an internationally recognized investment banking firm that has substantial experience in transactions similar to the merger. Pursuant to a letter agreement dated January 26, 2011, Pride engaged Goldman Sachs to act as its financial advisor in connection with the merger. Pursuant to the terms of the engagement letter, Pride has agreed to pay Goldman Sachs a transaction fee currently estimated to be approximately $42 million (which is based on the closing price of Ensco ADSs and Pride net debt as of March 31, 2011), of which $5 million became payable upon execution of the engagement letter and the remainder is contingent upon consummation of the merger. In addition, Pride has agreed to reimburse Goldman Sachs for its expenses, including attorneys’ fees and disbursements, and to indemnify Goldman Sachs and related persons against various liabilities, including certain liabilities under the federal securities laws.

Ensco Prospective Financial Information

Ensco is including selected prospective financial information based on estimates by Ensco management in this joint proxy statement/prospectus to provide its shareholders with access to certain non-public unaudited projected financial information that was made available to Pride and its financial advisor in connection with the merger. The unaudited prospective financial information does not give effect to the merger and does not take into account any circumstances or events occurring after January 21, 2011, the date it was prepared.

The unaudited prospective financial information was not prepared with a view toward public disclosure, and the inclusion of this information should not be regarded as an indication that any of Ensco, Ensco’s financial advisor, Pride, Pride’s financial advisor or any other recipient of this information considered, or now considers, it to be predictive of actual future results. The selected prospective financial information is not being included in this joint proxy statement/prospectus to influence shareholder’s decision whether to vote in favor of the issuance and delivery of Ensco ADSs pursuant to the merger, but because it represents prospective financial information prepared by management of Ensco in connection with due diligence. The information also was used for purposes of the financial analyses performed by Ensco’s financial advisor and was presented to the Ensco board of directors.

The unaudited prospective financial information was not prepared with a view toward complying with GAAP, the published guidelines of the SEC regarding projections or the guidelines established by the American Institute of Certified Public Accountants for preparation and presentation of prospective financial information. All of the unaudited prospective financial information was prepared by Ensco, and neither KPMG LLP nor any other independent accountants have compiled, examined or performed any procedures with respect to the unaudited prospective financial information contained herein, nor have they expressed any opinion or any other form of assurance on such information or its achievability. The report of Ensco’s independent registered public accounting firm contained in Ensco’s Annual Report on Form 10-K for the year ended December 31, 2010, which is incorporated by reference into this joint proxy statement/prospectus,

relates to Ensco’s historical financial information. It does not extend to the unaudited prospective financial information and should not be read to do so.

By including the unaudited prospective financial information in this joint proxy statement/prospectus, neither Ensco nor any of its representatives has made or makes any representation to any person regarding the ultimate performance of Pride or Ensco compared to the information contained in the unaudited prospective financial information.

Although presented with numeric specificity, the unaudited prospective financial information reflects numerous estimates and assumptions with respect to oil and gas industry activity, commodity prices, demand for natural gas and crude oil, global rig count, capacity utilization and general economic and regulatory conditions, and matters specific to Ensco’s business, including the following material assumptions and estimates as of January 21, 2011:


	•	contracted drilling rigs were estimated to continue at their contractual day rates through their firm contractual terms;

	•	future day rates for uncontracted rigs or rigs coming off contract were assumed to be consistent with Ensco management estimates as derived from current market tenders and activity by rig type and geographic location;

	•	utilization rates by rig type and geographic location were estimated based on current market trends;

	•	drilling operations for ENSCO 8503 and ENSCO 8504 were estimated to commence during the first and fourth quarters of 2011;

	•	ENSCO 7500 was estimated to be unutilized during the first half of the year as the rig is undergoing an enhancement project and estimated to return to near-full utilization in the third and fourth quarters of 2011;

	•	future operating cost estimates on a rig-by-rig basis were assumed to be consistent with historical cost information and management estimates by rig type and geographic location;

	•	management estimated a substantial decline in professional fees over the prior year due to professional fees incurred during 2010 in connection with various reorganization efforts undertaken as a result of Ensco’s redomestication to the U.K. in December 2009;

	•	capital expenditures for newbuild construction, rig enhancement projects and minor upgrades and improvements were generally consistent with management’s estimates that were disclosed in the Ensco Annual Report on Form 10-K for the year ended December 31, 2010;

	•	management estimated there to be no significant legislative changes affecting the offshore drilling industry;

	•	management estimated there to be no significant changes in prices of crude oil and natural gas that would affect demand for offshore drilling services;

	•	management estimated there to be no significant changes in expected downtime and repairs on drilling rigs except as noted above; and

	•	management estimated there to be no significant impact from pending litigation.

Many of these assumptions and estimates are beyond Ensco’s control. As a result, although this information was prepared by management of Ensco based on estimates and assumptions that management believed were reasonable at the time, there can be no assurance that the prospective results will be realized or that actual results will not be significantly higher or lower than estimated.

Form 10-K for the year ended December 31, 2010 and future SEC filings for Ensco’s actual results of operations and a description of risk factors with respect to Ensco’s business. See “Cautionary Statement Concerning Forward-Looking Statements” and “Where You Can Find More Information; Incorporation by Reference.” No representation is made by Pride, Ensco or any other person to any person regarding the ultimate performance of Ensco compared to the unaudited prospective financial information. No representation was made by Ensco to Pride in the merger agreement concerning this information.

The following table presents selected unaudited prospective financial information prepared by Ensco as of January 21, 2011:


	Year ended
	December 31,
	2011
	(in millions)

Operating revenues	$	1,745
Contract drilling expenses (exclusive of depreciation)		836
Depreciation expense		256
General and administrative expense		75
Capital expenditures		518

The above unaudited prospective financial information does not give effect to the merger.

Except as required by applicable securities laws, neither Pride nor Ensco intends to update or otherwise revise the prospective financial information to reflect circumstances existing after the date when made or to reflect the occurrence of future events, even in the event that any or all of the assumptions underlying such prospective financial information are no longer appropriate.

Pride Prospective Financial Information

Pride is including selected prospective financial information based on estimates by Pride management in this joint proxy statement/prospectus to provide its stockholders with access to certain non-public unaudited projected financial information that was made available to Ensco and its financial advisor in connection with the merger. The unaudited prospective financial information does not give effect to the merger and does not take into account any circumstances or events occurring after January 27, 2011, the date it was prepared.

The unaudited prospective financial information was not prepared with a view toward public disclosure, and the inclusion of this information should not be regarded as an indication that any of Pride, Pride’s financial advisor, Ensco, Ensco’s financial advisor or any other recipient of this information considered, or now considers, it to be predictive of actual future results. The selected prospective financial information is not being included in this joint proxy statement/prospectus to influence a stockholder’s decision whether to vote in favor of the adoption of the merger agreement, but because it represents prospective financial information prepared by management of Pride in connection with due diligence. The information also was used for purposes of the financial analyses performed by Pride’s financial advisor and was presented to the Pride board of directors.

The unaudited prospective financial information was not prepared with a view toward complying with GAAP, the published guidelines of the SEC regarding projections or the guidelines established by the American Institute of Certified Public Accountants for preparation and presentation of prospective financial information. All of the unaudited prospective financial information was prepared by Pride, and neither KPMG LLP nor any other independent accountants have compiled, examined or performed any procedures with respect to the unaudited prospective financial information contained herein, nor have they expressed any opinion or any other form of assurance on such information or its achievability. The report of Pride’s independent registered public accounting firm contained in Pride’s Annual Report on Form 10-K for the year ended December 31, 2010, which is incorporated by reference into this joint proxy statement/prospectus, relates to Pride’s historical financial information. It does not extend to the unaudited prospective financial information and should not be read to do so.

By including the unaudited prospective financial information in this joint proxy statement/prospectus, neither Pride nor any of its representatives has made or makes any representation to any person regarding the ultimate performance of Pride or Ensco compared to the information contained in the unaudited prospective financial information.

Although presented with numeric specificity, the unaudited prospective financial information reflects numerous estimates and assumptions with respect to oil and gas industry activity, commodity prices, demand for natural gas and crude oil, global rig count, capacity utilization and general economic and regulatory conditions, and matters specific to Pride’s business, including the following material assumptions as of January 27, 2011:


	•	near-term oil price in the range of $70 to $90 per barrel;

	•	the resumption of deepwater drilling activity in the U.S. Gulf of Mexico;

	•	incremental demand for newbuild ultra-deepwater rigs driven by pre-salt activity in deepwater offshore Brazil;

	•	the continued growth in the demand for deepwater drilling services globally and a shift in customer demand to newer higher specification rigs;

	•	increased regulatory requirements with respect to deepwater drilling activity, both domestically and internationally, and stronger contractual protections sought by customers;

	•	no significant changes to expected downtime, maintenance and recertification procedures applicable to floating rigs and jackups;

	•	operating costs generally expected to continue to increase 3-5% annually over the near term;

	•	no material change to historical effective tax rates;

	•	the reactivation of the Pride South Seas in mid third quarter of 2011; and

	•	the commencement of operations on full dayrate of the Deep Ocean Ascension in early second quarter of 2011, the Deep Ocean Clarion in late first quarter of 2011 and the Deep Ocean Mendocino in late second quarter of 2011.

Many of the above assumptions are beyond Pride’s control. As a result, although this information was prepared by management of Pride based on estimates and assumptions that management believed were reasonable at the time, there can be no assurance that the prospective results will be realized or that actual results will not be significantly higher or lower than estimated.

We caution you not to rely on the unaudited prospective financial information set forth below. We urge you to read carefully this entire joint proxy statement/prospectus, including the annexes and the other documents to which this joint proxy statement/prospectus refers or incorporates by reference, including Pride’s Annual Report on Form 10-K for the year ended December 31, 2010 and future SEC filings for Pride’s actual results of operations and a description of risk factors with respect to Pride’s business. See “Cautionary Statement Concerning Forward-Looking Statements” and “Where You Can Find More Information; Incorporation by Reference.” No representation is made by Pride, Ensco or any other person to any stockholder regarding the ultimate performance of Pride compared to the unaudited prospective financial information. No representation was made by Pride to Ensco in the merger agreement concerning this information.

The following table presents selected unaudited prospective financial information prepared by Pride as of January 27, 2011:


	Year ended
	December 31,
	2011
	(in millions)

Operating revenues including reimbursable revenues	$	2,039
Operating costs, excluding depreciation and amortization		1,057
General and administrative expense		95
Capital expenditures		1,159

In addition, the Base Case Forecasts for Pride provided to Goldman Sachs referred to above under “— Opinion of Goldman, Sachs & Co.” were based on this information but reflected a 0.2%, or $5 million, increase in revenues and a 1.5%, or $17 million, increase in total costs (all of which was included in operating costs and general and administrative expense) as compared to the prospective financial information presented above. The Base Case Forecasts for Ensco provided to Goldman Sachs by Pride reflected a 3.9%, or $68 million, decrease in revenues, a 1.0%, or $12 million, decrease in total costs (contract drilling expense, depreciation expense and general and administrative expense) and a substantial increase in capital expenditures as compared to the prospective financial information presented above under “— Ensco Prospective Financial Information.” The Base Case Forecasts reflected numerous estimates and assumptions as more fully set forth above.

Interests of the Pride Directors and Executive Officers in the Merger

In considering the recommendation of the Pride board of directors with respect to the merger, Pride stockholders should be aware that executive officers and directors of Pride have certain interests in the merger that may be different from, or in addition to, the interests of Pride stockholders generally.

The Pride board of directors was aware of the interests described in this section and considered them, among other matters, in approving the merger agreement and making its recommendation that the Pride stockholders adopt the merger agreement. See “— Recommendation of the Pride Board of Directors and Its Reasons for the Merger.”

These interests are summarized below. References in this section to Pride’s executive officers are to the following individuals: Louis A. Raspino, Imran Toufeeq, Brian C. Voegele, W. Gregory Looser, Lonnie D. Bane, Kevin C. Robert and Brady K. Long. For purposes of all the Pride plans and compensatory arrangements described in this section, consummation of the merger will constitute a change in control of Pride.

Ensco Board of Directors Following the Merger

The merger agreement provides that Ensco will take such actions as are necessary to expand the size of the Ensco board of directors and to appoint two current non-employee members of the Pride board of directors designated by Pride and reasonably acceptable to Ensco to fill such vacancies effective as of the effective time of the merger. Pride has not yet determined which of its current directors will be its designees on the Ensco board of directors as of the date of this joint proxy statement/prospectus. See “— Directors and Executive Officers of Ensco After the Merger.”

Treatment of Equity Incentive Awards

Pride’s executive officers have received, from time to time, awards consisting of restricted stock units, performance-based restricted stock units and options to acquire Pride common stock. Pride’s directors have received, from time to time, awards consisting of restricted stock units and options to acquire Pride common stock, all of which are fully vested as of January 31, 2011. Pursuant to the terms of Pride’s long-term incentive plans and the applicable award agreements thereunder, as a result of the merger all options to acquire Pride common stock will fully vest, all restrictions applicable to Pride restricted stock units will lapse and all performance-based restricted stock units will fully vest and will be earned based on actual performance as determined by Pride’s Compensation Committee prior to the merger. Options to acquire Pride common stock will remain outstanding and exercisable following the merger according to their original terms, provided that the options will be assumed by Ensco and converted into equivalent options to acquire Ensco ADSs based on an exchange ratio equal to 0.4778 plus a fraction obtained by dividing $15.60 by the average closing price of Ensco ADSs for the five trading days ending three trading days before the closing of the merger. See “The Merger Agreement — Merger Consideration — Treatment of Employee Stock Options and Other Equity

Awards.” The option term will be extended for certain of Pride’s executive officers pursuant to the terms of their employment arrangements described below.

Employment Agreements

Pride is party to employment agreements with each of its executive officers. Upon the occurrence of a change in control, the term of the employment agreements are automatically extended for two years. The employment agreements provide for change in control severance benefits in the event of certain qualifying terminations of employment in connection with or within two years after a change in control.

Under the employment agreements, if Pride terminates an executive officer’s employment without cause (as defined in the applicable agreement) or the executive officer terminates employment for good reason (as defined in the applicable agreement and as summarized below) at any time during the two-year period following a change in control, the executive will be eligible to receive the following payments and benefits in exchange for a timely executed release of claims against Pride and its affiliates:


	•	a lump sum cash payment equal to (i) two times (three times for Mr. Raspino and 1.5 times for Mr. Long) the executive’s annual base salary plus (ii) two times (three times for Mr. Raspino) the executive’s maximum bonus (1.5 times the target bonus for Mr. Long) under Pride’s annual incentive plan;

	•	life, health and accident and disability insurance continuation, at a cost to the executive at no more than the active employee rates for such coverage, for a period of two years (three years for Mr. Raspino and 1.5 years for Mr. Long) or until similar benefits are received from another employer, whichever is earlier; and

	•	immediate vesting of all equity awards, with options remaining outstanding until the later of two years after the change in control or 120 days after the executive officer’s termination, except for (i) Mr. Voegele, for whom such treatment is provided for in his equity award agreements, (ii) Mr. Raspino, whose options remain outstanding for their original term, and (iii) Mr. Long, whose options remain outstanding for 60 days after termination as provided in his equity award agreements.

For purposes of the employment agreements, “good reason” is defined generally to include (i) resignation requested by Pride other than for cause, (ii) a significant and adverse change in the nature or scope of position, authority or duties (including for Mr. Raspino, failure to be reelected to the board of directors), (iii) a significant and material diminution in duties and responsibilities that would degrade or embarrass the executive or otherwise make it unreasonable for the executive to remain employed, (iv) a reduction in base salary or target bonus, or a material reduction in other benefits, (v) a material breach of the employment agreement by Pride, (vi) any requirement that the executive relocate more than 50 miles from downtown Houston, Texas, or (vii) notice by Pride of non-renewal of the employment agreement prior to the employment period in which the executive attains age 65. Except for Mr. Long, if the executive voluntarily terminates employment within six months (12 months for Mr. Raspino) after a change in control, the executive is deemed to have an involuntary termination entitling the executive to receive the payments and benefits described above. The employment agreements require Pride to establish a rabbi trust prior to the consummation of a change in control and to fund the rabbi trust with the cash severance amounts described above.

The employment agreements provide that the executive officer is responsible for all income tax liability as a result of payments under the employment agreements, including any excise taxes imposed on excess parachute payments made on account of a change in control. In order to minimize excise tax liabilities, the employment agreements provide for a reduction of certain payments that are made as a result of a change in control. For Messrs. Raspino, Toufeeq, Voegele, Looser, Bane and Robert, if the reduction would reduce severance payments to the executive by 10% or more, the reduction will not apply, and the executive will receive a gross-up payment in an amount such that after payment of all taxes on the gross-up payment, the executive retains an amount of the gross-up payment equal to the excise taxes imposed on the executive’s severance payments. For Mr. Long, the reduction will not apply if the amount of Mr. Long’s benefit after paying the applicable taxes would exceed the benefit Mr. Long would receive if his payments were subject to the reduction.

Annual Incentive Plan and Non-Executive Retention Plan

Each of Pride’s executive officers participate in Pride’s annual incentive plan. In the event of a change in control, Pride’s annual incentive plan provides for payment of the executive officer’s maximum bonus for the year of the change in control, pro-rated for full months of service in such year prior to the date of the change in control. In addition, the merger agreement permits Pride, with the agreement of the Ensco senior executive in charge of human resources, to establish a retention plan for certain key employees (other than executive officers) up to a specified limit.

Supplemental Executive Retirement Plan

Pride’s executive officers, with the exception of Mr. Long, participate in Pride’s Supplemental Executive Retirement Plan, or SERP. Messrs. Raspino, Looser and Bane are fully vested in their SERP benefit. Messrs. Toufeeq, Voegele and Robert vest incrementally during their employment through the date of eligibility for early or normal retirement.

The SERP is intended to provide specified benefits to a select group of management and highly compensated employees of Pride. The SERP benefit at an executive’s “normal retirement date,” which is the date he attains age 62, is a lump sum payment equal to the actuarial present value of an annual benefit of 50% of his final annual pay payable for his lifetime. “Final annual pay” for purposes of the benefits calculations with respect to Messrs. Raspino, Looser and Bane means the executive’s base annual salary and target bonus award under Pride’s annual incentive plan as in effect on the executive’s last day of active employment. “Final annual pay” for purposes of the benefit calculations with respect to Messrs. Toufeeq, Voegele and Robert means the sum of (1) the executive’s average base annual salary over the five years preceding his last day of active employment and (2) the executive’s target bonus percentage under Pride’s annual incentive plan as in effect on the executive’s last day of active employment multiplied by the amount in clause (1) above.

If the executive officer’s employment is terminated involuntarily or for good reason within two years after a change in control, or in the event of a voluntary resignation by the executive within six months (12 months for Mr. Raspino) after a change in control, then the executive officer’s benefit under the SERP will fully vest and


	•	with respect to Messrs. Raspino, Toufeeq, Voegele and Robert, the executive will receive from us a lump sum payment in an amount equal to the actuarial present value of an annual benefit of 50% of his final annual pay payable for his lifetime and commencing on the first to occur of his early retirement date or his normal retirement date; and

	•	with respect to Messrs. Looser and Bane, in lieu of the lump sum benefit described above, the executive will receive from us a lump sum payment in an amount equal to the greater of his final annual pay at the time of the change in control or his final annual pay at the time of termination, multiplied by five.

The aggregate SERP benefits payable as a result of a change in control are required to be deposited into a rabbi trust prior to the change in control.

In addition, in connection with termination of employment with a vested right to a benefit under the SERP, the executive is entitled to receive retiree medical and dental coverage for himself, his spouse and his dependents who were covered under our group health plan as of the date of termination, with such coverage beginning immediately with respect to Messrs. Raspino, Looser and Bane and, with respect to Messrs. Toufeeq, Voegele and Robert, on his normal retirement date at age 62. The coverage will be provided until the later of the death of the executive or his surviving spouse. These benefits will be at least as favorable as the group medical and dental coverage offered to Pride’s active executive employees. This coverage (i) will be suspended during any period the executive has medical coverage provided by another employer, (ii) with respect to the executive and his spouse (if applicable), will be converted to Medicare Supplement coverage upon becoming eligible for and covered by Medicare and (iii) with respect to his dependents, will terminate at such time as the dependents are no longer eligible for coverage under the terms of Pride’s group health plan. Any retiree medical and dental benefits to the executive’s spouse or surviving spouse are available solely to the spouse to whom the executive was married on the date of the executive’s termination of employment. The executive or, if applicable, his surviving spouse will be responsible for the applicable premiums for coverage at the same

rate paid by active executive employees but not to exceed the cost of the most comprehensive group medical and dental coverage offered by Pride.

Summary of Estimated Value of Benefits Attributable to Change in Control

The following table sets forth the number of outstanding, unvested equity awards that will vest upon consummation of the merger for Pride’s executive officers and directors, as well as the estimated value of such awards. The chart also includes the amount of the estimated cash severance payments and the estimated value of other severance benefits that the executive officers would receive. The table is based on grants outstanding as of April 21, 2011 and assumes that the merger is completed on June 1, 2011 and that each executive officer experiences a severance-qualifying termination immediately thereafter.


	Louis A.		Imran		Brian C.		W. Gregory		Lonnie D.		Kevin C.		Brady K.
	Raspino		Toufeeq		Voegele		Looser		Bane		Robert		Long

Restricted stock units		157,699		50,245		55,509		52,959		34,807		33,647		28,342
Estimated value of restricted stock units(1)	$	6,811,020	$	2,170,082	$	2,397,434	$	2,287,299	$	1,503,314	$	1,453,214	$	1,224,091
Performance-based restricted stock units(2)		130,677		57,814		44,163		45,039		28,702		34,420		20,740
Estimated value of performance-based restricted stock units(1)	$	5,643,940	$	2,496,987	$	1,907,400	$	1,945,234	$	1,239,639	$	1,486,600	$	895,761
Shares subject to outstanding options		387,273		116,515		130,292		128,115		84,877		93,161		33,815
Estimated value of shares subject to outstanding options(1)	$	6,538,103	$	1,633,614	$	2,215,357	$	2,134,264	$	1,430,635	$	1,525,379	$	388,410
Estimated cash severance payments under employment agreements	$	8,550,000	$	2,600,000	$	2,112,000	$	2,136,000	$	1,628,000	$	1,725,000	$	888,000
Estimated pro-rated 2011 Annual Incentive Plan payment	$	791,666	$	325,000	$	256,666	$	259,583	$	185,000	$	203,125	$	185,000
Estimated enhanced SERP lump sum payment(3)	$	—	$	3,250,040	$	2,456,353	$	1,810,939	$	71,713	$	2,166,638	$	—
Estimated 280G gross-up amount	$	—	$	4,075,117	$	3,223,564	$	2,303,846	$	—	$	2,633,261	$	—


(1)		Estimated value is based on the closing price of Pride common stock as of April 21, 2011 at $43.19. The estimated option value represents $43.19 less the applicable exercise price multiplied by the number of option shares.


(2)		The number of performance-based restricted stock units to be earned depends upon the satisfaction of certain performance goals. This chart assumes that all unvested performance goals will be achieved at the maximum level. On March 9, 2011, Pride’s executive officers vested in the following number of earned performance-based restricted stock units: Mr. Raspino — 17,532 units; Mr. Toufeeq — 7,452 units; Mr. Voegele — 6,137 units; Mr. Looser — 6,137 units; Mr. Bane — 3,945 units; Mr. Robert — 4,384 units and Mr. Long — 1,772 units. Pursuant to the terms of Pride’s long-term incentive plan and the applicable award agreements, as a result of the merger, all remaining performance-based restricted stock units will fully vest and will be earned based on actual performance as determined by Pride’s Compensation Committee prior to the merger. Further, as a result of the merger, all earned performance-based restricted stock units will be paid on the effective date of the merger.

(3)		Represents the increase in SERP benefit as a result of the merger. Mr. Raspino is fully vested in his SERP and not entitled to enhanced SERP benefits as a result of the merger.

Pride’s directors will not receive any additional or enhanced payments as a result of the merger. All of the outstanding restricted stock unit and option awards of Pride’s directors are fully vested as of January 31, 2011.

Indemnification and Insurance

The merger agreement provides for indemnification and advancement of expenses in favor of the current and former directors and officers of Pride and its subsidiaries and for the purchase of directors’ and officers’ liability insurance and fiduciary liability insurance tail policies with respect to matters existing or occurring at or prior to the effective time of the merger. These interests are described in more detail below at “The Merger Agreement — Additional Agreements — Indemnification and Insurance.”

Directors and Executive Officers of Ensco After the Merger

Ownership of Ensco After the Merger

Regulatory Approvals

Antitrust Approvals

The merger is also subject to antitrust review by government authorities in Brazil, which does not require governmental approval prior to the closing of the transaction.

There can be no assurance that the merger will not be challenged on antitrust or competition grounds or, if a challenge is made, what the outcome would be. The Antitrust Division, the FTC, any U.S. state and other applicable U.S. or non-U.S. regulatory bodies may challenge the merger on antitrust or competition grounds at any time, including after the termination of the waiting period under the HSR Act or other applicable process, as they may deem necessary or desirable or in the public interest. Accordingly, at any time before or after the completion of the merger, any such party could take action under the antitrust laws, including, without limitation, by seeking to enjoin the effective time of the merger or permitting completion subject to regulatory concessions or conditions. Private parties may also seek to take legal action under antitrust or competition laws under certain circumstances.

Other Regulatory Procedures

The merger may be subject to certain regulatory requirements of other municipal, state and federal, domestic or foreign, governmental agencies and authorities, including those relating to the offer and sale of securities. Ensco and Pride are currently working to evaluate and comply in all material respects with these requirements, as appropriate, and do not currently anticipate that they will hinder, delay or restrict completion of the merger.

It is possible that one or more of the regulatory approvals required to complete the merger will not be obtained on a timely basis or at all. In addition, it is possible that any of the governmental entities with which filings are made may seek regulatory concessions as conditions for granting approval of the merger. Under the merger agreement, Ensco and Pride have each agreed to use its reasonable best efforts to take all actions necessary, proper or advisable to complete the merger and the other transactions contemplated by the merger agreement, including to gain clearance from antitrust authorities and obtain other required approvals. See “The Merger Agreement — Additional Agreements — Efforts Related to Consents and Approvals of Governmental Entities and Third Parties.”

Although Ensco and Pride do not expect antitrust or other regulatory authorities to raise any significant objections to the merger that would result in the failure to satisfy the conditions to closing the merger by the termination date, Ensco and Pride can provide no assurance that all required regulatory approvals will be obtained or that these approvals will not contain terms, conditions or restrictions that would be detrimental to Ensco after the effective time of the merger. Ensco and Pride have not yet obtained any of the regulatory approvals required to complete the merger.

Material U.S. Federal Income Tax Consequences of the Merger

Scope of Discussion

The following discussion summarizes the material U.S. federal income tax consequences of the merger and of holding and disposing of Ensco ADSs that may be relevant to Pride stockholders. This discussion does not address any aspects of U.S. taxation other than U.S. federal income taxation, is not a complete analysis or listing of all potential tax consequences of the merger or of holding and disposing of Ensco ADSs, and does not address all tax considerations that may be relevant to Pride stockholders. In particular, the discussion below addresses only the U.S. federal income tax consequences to Pride stockholders who hold their shares of Pride common stock, and who will hold their Ensco ADSs, solely as capital assets. The discussion below does not address any tax consequences to Pride stockholders who are subject to special rules under U.S. federal income tax laws, such as:


	•	banks, financial institutions or insurance companies;

	•	tax-exempt entities, including an “individual retirement account” or “Roth IRA”;


If you are an Ensco shareholder:		If you are a Pride stockholder:

Proxy Solicitor: D.F. King & Co., Inc. 48 Wall Street, 22nd Floor New York, New York 10005 Shareholders Call Toll-Free at: 1-800-859-8509 Banks and Brokers Call Collect at: 1-212-269-5550 Email: ensco@dfking.com		Proxy Solicitor: Innisfree M&A Incorporated 501 Madison Avenue, 20th Floor New York, NY 10022 Shareholders Call Toll-Free at: (877) 825-8772 Banks and Brokers Call Collect at: (212) 750-5833


	As of December 31,
	2010		2009		2008		2007		2006
	(In millions)

Balance Sheet Data:
Working capital	$	463.1	$	661.8	$	849.6	$	888.0	$	293.1
Property and equipment, net		5,961.2		4,890.3		4,592.9		4,021.4		4,000.3
Total assets		6,871.7		6,142.9		6,069.0		5,615.6		5,097.6
Long-term debt, net of current portion		1,833.4		1,161.7		692.9		1,111.9		1,280.2
Stockholders’ equity		4,516.3		4,257.8		4,400.0		3,474.0		2,643.5


	Page

QUESTIONS AND ANSWERS ABOUT THE MEETINGS		1
SUMMARY		9
The Companies		9
The Merger		10
Recommendation of the Ensco Board of Directors		10
Recommendation of the Pride Board of Directors		10
Stockholders Entitled to Vote; Vote Required		11
Opinions of Financial Advisors		12
Directors and Executive Officers of Ensco After the Merger		13
Ownership of Ensco After the Merger		13
Share Ownership of Directors and Executive Officers of Ensco		14
Share Ownership of Directors and Executive Officers of Pride		14
Interests of the Pride Directors and Executive Officers in the Merger		14
Listing of Ensco ADSs; Delisting and Deregistration of Shares of Pride Common Stock		15
Appraisal Rights in the Merger		15
Conditions to Completion of the Merger		15
Regulatory Approvals Required for the Merger		16
No Solicitation and Change in Recommendation		16
Termination of the Merger Agreement		16
Termination Fees		17
Material U.S. Federal Income Tax Consequences of the Merger		18
Material U.K. Tax Consequences of the Merger		18
Accounting Treatment		19
Payment of Dividends		19
Description of Debt Financing		19
Comparison of Rights of Pride Stockholders and Ensco Shareholders		19
Litigation Relating to the Merger		19
Selected Historical Financial Data of Ensco		21
Selected Historical Financial Data of Pride		22
Selected Unaudited Pro Forma Condensed Combined Financial Information		24
Unaudited Comparative Per Share Data		25
Comparative Ensco and Pride Market Price and Dividend Data		26
RISK FACTORS		28
Risk Factors Relating to the Merger		28
Risk Factors Relating to the Combined Company Following the Merger		33
Risk Factors Relating to Ensco ADSs Following the Merger		45
CAUTIONARY STATEMENT CONCERNING FORWARD-LOOKING STATEMENTS		45
THE MERGER		48
Background of the Merger		48
Recommendation of the Ensco Board of Directors and Its Reasons for the Merger		63
Recommendation of the Pride Board of Directors and Its Reasons for the Merger		66
Opinion of Deutsche Bank Securities Inc.		70
Opinion of Goldman, Sachs & Co.		80


	Page

Ensco Prospective Financial Information		86
Pride Prospective Financial Information		88
Interests of the Pride Directors and Executive Officers in the Merger		90
Directors and Executive Officers of Ensco After the Merger		94
Ownership of Ensco After the Merger		94
Regulatory Approvals		94
Material U.S. Federal Income Tax Consequences of the Merger		95
Material U.K. Tax Consequences of the Merger		100
Accounting Treatment		104
Listing of Ensco American Depositary Shares		104
Delisting and Deregistration of Pride Common Stock		104
Restrictions on Sales of Shares of Ensco American Depositary Shares Received in the Merger		105
Litigation Relating to the Merger		105
THE MERGER AGREEMENT		107
Structure of the Merger		107
Effective Time of the Merger		107
Merger Consideration		108
Exchange of Certificates		110
Representations and Warranties		112
Conditions to the Completion of the Merger		114
Conduct of Business Pending the Merger		115
Additional Agreements		118
Termination of the Merger Agreement		126
Termination Fees		128
APPRAISAL RIGHTS		130
DESCRIPTION OF DEBT FINANCING		134
UNAUDITED PRO FORMA CONDENSED COMBINED FINANCIAL STATEMENTS		135
DESCRIPTION OF CLASS A ORDINARY SHARES OF ENSCO		146
DESCRIPTION OF AMERICAN DEPOSITARY SHARES OF ENSCO		152
COMPARISON OF RIGHTS OF PRIDE STOCKHOLDERS AND ENSCO SHAREHOLDERS		160
THE ENSCO GENERAL MEETING		185
THE PRIDE SPECIAL MEETING		188
SHAREHOLDER PROPOSALS		191
LEGAL MATTERS		192
EXPERTS		192
WHERE YOU CAN FIND MORE INFORMATION; INCORPORATION BY REFERENCE		193


Annexes

Annex A		Agreement and Plan of Merger (composite as amended)
Annex B		Opinion of Deutsche Bank Securities Inc.
Annex C		Opinion of Goldman, Sachs & Co.
Annex D		Section 262 of the General Corporation Law of the State of Delaware


Q:	Who can answer my questions?

A:	If you have any questions about the merger or how to submit your proxy or voting instructions, or if you need additional copies of this joint proxy statement/prospectus, the enclosed proxy or voting instructions card, you should contact: