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As filed with the Securities and Exchange Commission on
    August 17, 2007
 Registration
    No. 333-
    UNITED STATES SECURITIES AND
    EXCHANGE COMMISSION
 Washington, D.C.
    20549
      Form S-4
 REGISTRATION
    STATEMENT
 UNDER
 THE SECURITIES ACT OF
    1933
       CAL DIVE INTERNATIONAL,
    INC.
 (Exact name of registrant as
    specified in its charter)
  Delaware

1389

61-1500501(State or other jurisdiction
    of
    incorporation or organization)

(Primary Standard Industrial
    Classification Code Number)

(I.R.S. Employer
    Identification Number)       400 North Sam Houston Parkway,
    E., Suite 1000
 Houston, Texas 77060
 (281) 618-0400
 (Address, including zip code,
    and telephone number, including area code, of registrants
    principal executive offices)
      Lisa Manget Buchanan
 400 North Sam Houston Parkway,
    E., Suite 1000
 Houston, Texas 77060
 (281) 618-0400
 (Name, address, including zip
    code, and telephone number, including area code, of agent for
    service)
      Copies To:
  David S. Peterman
    Fulbright & Jaworski L.L.P.
    1301 McKinney, Suite 5100
    Houston, Texas 77010
    Telephone: (713) 651-5151
    Facsimile: (713) 651-5246

William B. Gibbens, III
    Horizon Offshore, Inc.
    2500 CityWest Boulevard, Suite 2200
    Houston, Texas  77042
    Facsimile: (713) 361-2693

William B. Masters
    Jones, Walker, Waechter, Poitevent,
    Carrère & Denègre, L.L.P.
    201 St. Charles Avenue, Suite 5100
    New Orleans, Louisiana  70170
    Facsimile: (504) 582-8012       Approximate date of commencement of proposed sale to the
    public:
  o
  o
  o
      CALCULATION OF REGISTRATION
    FEE
  Proposed Maximum


Proposed MaximumTitle of Each Class of


Amount to


Offering Price


Aggregate


Amount ofSecurities to be Registered(1)


be Registered(2)


per Share


Offering Price(3)


Registration FeeCommon stock, par value $0.01 per
    share


20,383,885


N/A


$191,445,442.05


$5,877.38   (1)
    
    This registration statement relates
    to shares of common stock, par value $.01, of Cal Dive
    International, Inc. (Cal Dive) issuable to holders
    of common stock, par value $.00001 per share, of Horizon
    Offshore, Inc. (Horizon) pursuant to the Merger
    Agreement.(2)
    
    The maximum number of shares of Cal
    Dive common stock issuable in connection with the merger in
    exchange for shares of Horizon common stock, based on the number
    of shares of Horizon common stock exchangeable in the merger, is
    equal to 32,614,215 shares of Horizon common stock
    outstanding on August 17, 2007 (including
    432,820 shares of restricted stock), multiplied by an
    exchange ratio of 0.625 of a share of Cal Dive common stock for
    each share of Horizon common stock.(3)
    
    Estimated solely for the purpose of
    calculating the registration fee pursuant to Rule 457(c),
    Rule 457(f)(1) and Rule 457(f)(3) of the Securities
    Act, based on the market value of the shares of Horizon common
    stock to be exchanged in the merger, as established by the
    average of the high and low prices of Horizon common stock as
    reported on the Nasdaq Global Market on August 15, 2007,
    which was $15.12, less the amount of cash to be paid by Cal Dive
    in exchange for shares of Horizon common stock (equal to $9.25
    multiplied by 32,614,215, the number of shares of Horizon common
    stock set forth above, or $301,681,489).  The Registrant hereby amends this Registration Statement on
    such date or dates as may be necessary to delay its effective
    date until the Registrant shall file a further amendment that
    specifically states that this Registration Statement shall
    thereafter become effective in accordance with Section 8(a)
    of the Securities Act of 1933, or until the Registration
    Statement shall become effective on such date as the Securities
    and Exchange Commission, acting pursuant to said
    Section 8(a), may determine.




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The
information contained in this information statement/proxy
statement/prospectus is not complete and may be changed. These
securities may not be sold until the registration statement
filed with the Securities and Exchange Commission, of which this
document is a part, is effective. This information
statement/proxy statement/prospectus is not an offer to sell
these securities, and it is not soliciting an offer to buy these
securities, in any state where the offer or sale is not
permitted.  SUBJECT TO COMPLETION, DATED
    AUGUST 17, 2007
  cal dive logo

horizon offshore logo   INFORMATION STATEMENT/PROXY STATEMENT/PROSPECTUS
 Proposed Merger  Your Vote Is Very Important
            In particular, you should consider the matters
    discussed under Risk Factors beginning on
    page 7 of this information statement/proxy
    statement/prospectus.
  Quinn J. Hébert

David W. SharpPresident and Chief Executive
    Officer

President and Chief Executive
    OfficerCal Dive International, Inc.

Horizon Offshore, Inc.   Neither the Securities and Exchange Commission nor any state
    securities commission has approved or disapproved of the
    securities to be issued in connection with the merger or passed
    upon the adequacy or accuracy of this information
    statement/proxy statement/prospectus. Any representation to the
    contrary is a criminal offense.




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REFERENCES
    TO ADDITIONAL INFORMATION
    www.horizonoffshore.com www.sec.gov
  Horizon will provide you with copies of the documents
    relating to Horizon incorporated by reference, excluding any
    exhibits to those documents, without charge, if you request it
    in writing or by telephone from:
       (713) 361-2600
  In order for you to receive timely delivery of the documents
    in advance of the Horizon special meeting, Horizon should
    receive your request no later
    than          ,
    2007.




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Cal Dive International, Inc.
  NOTICE OF APPROVAL GIVEN AND ACTION TO BE TAKEN
    WE ARE NOT ASKING YOU FOR YOUR PROXY AND YOU ARE REQUESTED
    NOT TO SEND US A PROXY. THE ACTIONS DESCRIBED BELOW HAVE ALREADY
    BEEN APPROVED BY WRITTEN CONSENT OF HOLDERS OF A MAJORITY OF CAL
    DIVE INTERNATIONAL, INC.S OUTSTANDING SHARES OF VOTING
    STOCK. A VOTE OF THE REMAINING STOCKHOLDERS IS NOT NECESSARY.
             Secretary




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Horizon Offshore, Inc.
  NOTICE OF SPECIAL MEETING OF STOCKHOLDERS
 TO BE
    HELD          ,
    2007
              THE BOARD OF DIRECTORS OF HORIZON HAS CAREFULLY CONSIDERED
    THE TERMS OF THE MERGER AGREEMENT AND THE MERGER AND BELIEVES
    THAT THE MERGER IS ADVISABLE AND FAIR TO, AND IN THE BEST
    INTERESTS OF, HORIZON AND ITS STOCKHOLDERS. THE BOARD OF
    DIRECTORS HAS UNANIMOUSLY APPROVED THE MERGER AGREEMENT AND THE
    MERGER AND UNANIMOUSLY RECOMMENDS THAT STOCKHOLDERS VOTE FOR
    APPROVAL AND ADOPTION OF THE MERGER AGREEMENT.
    It is important that your stock be represented at the special
    meeting regardless of the number of shares you hold. Please
    promptly mark, date, sign, and return the enclosed proxy in the
    accompanying envelope, whether or not you intend to be present
    at the special meeting. In some cases, you may be able to
    instruct your bank or brokerage firm how to exercise your proxy
    by telephone or the Internet. See Information About the
    Special Meeting and Voting beginning on page 30. Your
    proxy is revocable at any time prior to its use at the special
    meeting.
  Please do not send your Horizon common stock certificates
    with the enclosed proxy. If the merger is completed, the
    exchange agent will send you instructions regarding the
    surrender of your stock certificates.




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In connection with the proposed merger, you may exercise
    appraisal rights as provided in the Delaware General Corporation
    Law. The procedure for exercising your appraisal rights is
    summarized under the heading Appraisal Rights in the
    attached information statement/proxy statement/prospectus.
     Secretary




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TABLE OF
    CONTENTS
  PageQuestions and
    Answers About the Merger and the Special Meeting


vSummary


1The
    Companies


1The
    Merger


1Risk
    Factors


2Material U.S.
    Federal Income Tax Consequences of the Merger to Horizon
    Stockholders


2Recommendation of
    the Horizon Board of Directors


3Opinion of Lehman
    Brothers Inc.  Financial Advisor to Horizon


3Ownership of Cal
    Dive Following the Merger


3Board of Directors
    of Cal Dive Following the Merger


3Market Prices and
    Share Information


3Interests of
    Horizon Directors and Executive Officers in the Merger


4Conditions to
    Completion of the Merger


4Regulatory
    Matters


5Termination of the
    Merger Agreement


5Non Solicitation
    Provisions and Acquisition Proposals


5Fees and
    Expenses


5Accounting
    Treatment


6Comparison of
    Stockholders Rights


6Risk
    Factors


7Risks Relating to
    the Merger


7Risks Relating to
    Cal Dive


12Cautionary
    Statement Regarding Forward-Looking Statements


20Selected Historical
    and Unaudited Pro Forma Financial Information


22Selected Cal Dive
    Historical Financial Data


22Selected Horizon
    Historical Financial Data


25Selected Unaudited
    Condensed Combined Pro Forma Financial Data


27Comparative
    Historical and Pro Forma Per Share Information


28Comparative Market
    Value Information


29Stockholder
    Litigation


29Information About
    The Special Meeting and Voting


30Date, Time and
    Place


30Matters to be
    Considered


30Stockholders
    Entitled to Vote


30Quorum and Required
    Vote


30How Shares Will Be
    Voted at the Special Meeting


31How to Vote Your
    Shares


31How to Change Your
    Vote


32Voting by
    Participants in the Horizon Benefit Plans


32Solicitation of
    Proxies


32Recommendation of
    the Horizon Board of Directors


32Special Meeting
    Admission


32Adjournment and
    Postponements


33




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PageThe
    Merger


33General


33Background of the
    Merger


33Horizons
    Reasons for the Merger


39Recommendation of
    the Horizon Board of Directors


41Opinion of Lehman
    Brothers Inc.  Financial Advisor to Horizon


41Cal Dives
    Reasons for the Merger


49Opinion of Banc of
    America Securities LLC  Financial Advisor to Cal
    Dive


50Accounting
    Treatment


57Opinions that the
    Merger Constitutes a Reorganization under Section 368(a) of
    the Internal Revenue Code


57Regulatory
    Matters


57Appraisal
    Rights


57Delisting and
    Deregistration of Horizon Common Stock


60Federal Securities
    Laws Consequences; Resale Restrictions


60Interests of
    Horizon Directors and Executive Officers in the Merger


60Stock Options and
    Restricted Stock


61Change in Control
    Severance Agreements


61Positions of
    Certain Horizon Executive Officers After the Merger


62Indemnification of
    Horizon Officers and Directors


62D&O
    Insurance


62Ownership of
    Horizon Common Stock


62Retention Bonus
    Plan for Salaried Personnel


62Material U.S.
    Federal Income Tax Consequences


63General


63Tax Consequences of
    the Merger to Horizon Stockholders


64The Merger
    Agreement


66Structure of the
    Merger


67Timing of
    Closing


67Merger
    Consideration


67Fractional
    Shares


67Potential
    Adjustment to Merger Consideration


67Treatment of
    Horizon Stock Options and Restricted Stock


67Conversion of
    Shares


68Exchange
    Procedures


68Managers and
    Officers of the Surviving Company After the Merger


69Representations and
    Warranties


69Covenants and
    Agreements


70Operating
    Covenants  Horizon


70Operating
    Covenants  Cal Dive


71No Control of Other
    Partys Business


72Non-Solicitation
    Provisions and Acquisition Proposals


72Employee Benefit
    Matters


74Directors and
    Officers Indemnification and Insurance


75 ii




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PageAffiliate
    Agreements


75Tax
    Matters


75Additional
    Agreements


75Conditions
    Precedent


76Conditions to Each
    Partys Obligation to Effect the Merger


76Conditions to
    Obligations of Cal Dive


76Conditions to
    Obligations of Horizon


77Termination


77Fees and
    Expenses


78Amendment


78Extension;
    Waiver


78Information About
    Cal Dive


79Business


79Properties


89Insurance and Legal
    Proceedings


91Market for Cal
    Dives Common Stock and Related Stockholder
    Matters


92Dividend
    Policy


92Managements
    Discussion and Analysis of Financial Condition and Results of
    Operations


92Market Risk
    Management


106Changes in and
    Disagreements with Accountants on Accounting and Financial
    Disclosure


107Directors and
    Executive Officers


107Certain
    Relationships and Related Transactions


109Board of Directors
    Independence


110Compensation
    Committee Interlocks and Inside Participation


110Compensation
    Discussion and Analysis


111Director
    Compensation


117Executive
    Compensation


118Beneficial
    Ownership of Cal Dives Common Stock


126Information About
    Horizon


127General Development
    of Horizons Business


127Directors and
    Executive Officers


128Beneficial
    Ownership of Horizons Common Stock


128Cal Dives
    Financial Statements and Supplementary Data


129Unaudited Condensed
    Combined Pro Forma Financial Data


164Description of Cal
    Dive Capital Stock


169Common
    Stock


169Preferred
    Stock


169Purposes and
    Effects of Certain Provisions of Cal Dives Amended and
    Restated Certificate of Incorporation and Bylaws


170Limitation on
    Foreign Ownership of Common Stock


173Corporate
    Opportunity


173Transfer Agent and
    Registrar


173New York Stock
    Exchange Listing


173Comparison of
    Stockholders Rights


173 iii




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PageProposed
    Financings


178Legal
    Matters


178Experts


178Stockholder
    Proposals


179Where You Can Find
    More Information


179ANNEXESAnnex A
    Agreement and Plan of Merger, dated as of June 11,
    2007


A-1Annex B
    Opinion of Lehman Brothers Inc., dated June 11, 2007


B-1Annex C
    Opinion of Banc of America Securities LLC, dated June 11,
    2007


C-1Annex D
    Section 262 of the Delaware General Corporation
    Law


D-1SubsidiariesConsent of Ernst & Young LLPConsent of Grant Thornton LLPConsent of Spears & Associates, IncForm of Proxy of Horizon Offshore, IncConsent of Prospective Director for David W. SharpConsent of Prospective Director for John T. Mills    No person is authorized to give any information or to make
    any representation with respect to the matters described in this
    information statement/proxy statement/prospectus other than
    those contained herein or in the documents incorporated by
    reference herein and, if given or made, such information or
    representation must not be relied upon as having been authorized
    by Cal Dive or Horizon. This information statement/proxy
    statement/prospectus does not constitute an offer to sell or a
    solicitation of an offer to buy the securities offered by this
    information statement/proxy statement/prospectus or a
    solicitation of a proxy in any jurisdiction where, or to any
    person whom, it is unlawful to make such an offer or
    solicitation. Neither the delivery hereof nor any distribution
    of securities made hereunder shall, under any circumstances,
    create an implication that there has been no change in the
    affairs of Cal Dive or Horizon since the date hereof or
    that the information contained or incorporated by reference in
    this information statement/proxy statement/prospectus is correct
    as of any time subsequent to the date hereof.
 iv




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QUESTIONS
    AND ANSWERS ABOUT THE MERGER AND THE SPECIAL MEETING  The following questions and answers briefly address some
    commonly asked questions about the special meeting and the
    merger. They may not include all the information that is
    important to you. We urge you to read carefully this entire
    information statement/proxy statement/prospectus, including the
    annexes and the other documents we refer to in this information
    statement/proxy statement/prospectus.
  Frequently
    Used Terms
    
    Cal Dive International, Inc., a Delaware corporation, as
    Cal Dive;
    Horizon Offshore, Inc., a Delaware corporation, as
    Horizon;
    Cal Dive Acquisition, LLC, a newly formed Delaware limited
    liability company and a wholly-owned subsidiary of
    Cal Dive, as Merger Sub;
    Helix Energy Solutions Group, Inc., a Minnesota corporation, as
    Helix;
    the merger of Horizon into Merger Sub and the conversion of
    shares of Horizon common stock into the right to receive cash
    and shares of Cal Dive common stock as the
    merger;
    the Agreement and Plan of Merger, dated as of June 11,
    2007, among Cal Dive, Merger Sub, and Horizon as the
    merger agreement;
    the
    Hart-Scott-Rodino
    Antitrust Improvements Act of 1976, as amended, as the HSR
    Act or the
    Hart-Scott-Rodino
    Act; and
    the General Corporation Law of the State of Delaware as the
    DGCL.  About the
    Merger
  Q1:
    
    What am I voting on?A1:
    
    Cal Dive is proposing to acquire Horizon. Horizon stockholders
    are being asked to vote to approve and adopt the merger
    agreement. In the merger, Horizon will merge into Merger Sub.
    Merger Sub would be the surviving entity in the merger and would
    remain a wholly-owned subsidiary of Cal Dive, and Horizon would
    no longer be a separate company.Horizon is also seeking your approval of a proposal to adjourn
    or postpone the special meeting, if necessary, to solicit
    additional proxies in favor of approval and adoption of the
    merger agreement.Q2:
    
    What will I receive in exchange for my Horizon shares?A2:
    
    Upon completion of the merger, you will receive a combination of
    $9.25 in cash, without interest, and 0.625 of a share of Cal
    Dive common stock, for each share of Horizon common stock that
    you own. We refer to the aggregate amount of the stock
    consideration and cash consideration to be received by Horizon
    stockholders pursuant to the merger as the merger consideration.
    The merger consideration is not subject to any adjustment. No
    fractional shares will be issued. In lieu of any fractional
    shares, the holder of any fractional share will receive cash
    equal to the product of such fractional share and the average
    closing sales price of Cal Dives common stock on the New
    York Stock Exchange for the 20 trading days immediately
    preceding the third trading day before the closing.Q3:
    
    Do I have the option to receive all cash consideration or all
    stock consideration for my Horizon shares?A3:
    
    No. All Horizon stockholders will receive the fixed
    combination of the cash consideration and the stock
    consideration for each share of Horizon common stock that they
    own. v




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Q4:
    
    What are the U.S. federal income tax consequences of the
    merger to me?A4:
    
    The merger is intended to constitute a
    reorganization within the meaning of
    Section 368(a) of the Internal Revenue Code of 1986, as
    amended, or the Code. Assuming the merger qualifies as a
    reorganization within the meaning of
    Section 368(a) of the Code, a Horizon stockholder who
    exchanges, in the merger, his Horizon shares for cash and Cal
    Dive shares will recognize gain (but not loss) in an amount
    equal to the lesser of: the amount of cash received pursuant to the merger
    (excluding any cash received in lieu of fractional shares of Cal
    Dive common stock), and the amount, if any, by which the sum of the fair
    market value of the shares of Cal Dive common stock as of the
    effective time of the merger and the amount of cash received
    pursuant to the merger for those Horizon shares exceeds his
    adjusted tax basis in those Horizon shares.The merger is conditioned on the receipt of legal opinions to
    the effect that the merger will constitute a
    reorganization within the meaning of
    Section 368(a) of the Code.For a more complete discussion of the U.S. federal income tax
    consequences of the merger, see Material U.S. Federal
    Income Tax Consequences beginning on page 63 of this
    information statement/proxy statement/prospectus.Tax matters are very complicated and the tax consequences
    of the merger to any particular Horizon stockholder will depend
    on that stockholders particular situation. Horizon
    stockholders should consult their own tax advisor to determine
    the specific tax consequences of the merger to them.Q5:
    
    What is the required vote to approve and adopt the merger
    agreement?A5:
    
    Holders of a majority of the outstanding shares of Horizon
    common stock entitled to vote at the special meeting must vote
    to approve and adopt the merger agreement to complete the
    merger. Cal Dive has already received approval of the issuance
    of its common stock in the merger by the holder of a majority of
    its outstanding shares.Q6:
    
    What happens if I do not vote?A6:
    
    Because the required vote of Horizon stockholders is based upon
    the number of outstanding shares of Horizon common stock
    entitled to vote rather than upon the number of shares actually
    voted, abstentions from voting and broker non-votes
    will have the same effect as a vote AGAINST approval and
    adoption of the merger agreement. If you return a properly
    signed proxy card but do not indicate how you want to vote, your
    proxy will be counted as a vote FOR approval and adoption of the
    merger agreement and FOR approval of any proposal to adjourn or
    postpone the special meeting to solicit additional proxies in
    favor of approval and adoption of the merger agreement.Q7:
    
    How does the Horizon board of directors recommend I vote?A7:
    
    The board of directors of Horizon unanimously recommends that
    Horizons stockholders vote FOR approval and adoption of
    the merger agreement. The Horizon board of directors believes
    the merger is advisable and in the best interests of Horizon and
    its stockholders.Q8:
    
    Do I have appraisal rights with respect to the merger?A8:
    
    Yes. Under Delaware law, a Horizon stockholder has the right to
    dissent from the merger and, in lieu of receiving the merger
    consideration, obtain payment in cash of the fair value of your
    shares of Horizon common stock as determined by the Delaware
    Chancery Court. To exercise appraisal rights, a Horizon
    stockholder must strictly follow the procedures prescribed by
    Section 262 of the DGCL. See The Merger 
    Appraisal Rights beginning on page 57 of this
    information statement/proxy statement/prospectus. In addition,
    the full text of the applicable provisions of Delaware law is
    included as Annex D to this information statement/proxy
    statement/prospectus. vi




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Q9:
    
    Will the rights of a Horizon stockholder change as a result
    of the merger?A9:
    
    Yes. Through the date of the merger, the rights of Cal Dive
    stockholders will continue to be governed by Cal Dives
    certificate of incorporation and bylaws, and the rights of
    Horizon stockholders will continue to be governed by
    Horizons certificate of incorporation and bylaws. Upon
    completion of the merger, Horizon stockholders will become Cal
    Dive stockholders and their rights will then be governed by Cal
    Dives certificate of incorporation and bylaws. Please read
    carefully the summary of the material differences between the
    rights of Cal Dive stockholders and Horizon stockholders under
    Comparison of Stockholders Rights beginning on
    page 173 of this information statement/proxy
    statement/prospectus.Q10:
    
    What will happen to shares of Cal Dive common stock in the
    merger?A10:
    
    Each outstanding share of Cal Dive common stock will remain
    outstanding as a share of Cal Dive common stock.Q11:
    
    Will Horizon stockholders be able to trade the Cal Dive
    common stock that they receive in the merger?A11:
    
    The shares of Cal Dive common stock issued in connection with
    the merger will be freely tradable, unless you are an affiliate
    of Horizon, and will be quoted on the New York Stock Exchange
    under the symbol DVR. Generally, persons who are
    deemed to be affiliates (generally directors, officers and 10%
    or greater stockholders) of Horizon must comply with
    Rule 145 under the Securities Act of 1933 if they wish to
    sell or otherwise transfer any of the shares of Cal Dive common
    stock they receive in the merger. You will be notified if you
    are an affiliate of Horizon.Q12:
    
    Are there risks associated with the merger or owning Cal Dive
    common stock that I should consider in deciding how to vote?A12:
    
    Yes. There are risks associated with all business combinations,
    including the merger of our two companies. In particular, the
    implied value of the stock consideration will fluctuate as the
    market price of Cal Dive common stock fluctuates. Accordingly,
    the value of the Cal Dive common stock that Horizon stockholders
    will receive in return for their Horizon common stock may be
    less than or more than the value of the Cal Dive common stock as
    of the date of the merger agreement or the date of this
    information statement/proxy statement/prospectus. There are a
    number of other risks that are discussed in this document and in
    other documents incorporated by reference in this document.
    Please read with particular care the more detailed
    description of the risks associated with the merger and the
    ownership of Cal Dive common stock discussed under Risk
    Factors beginning on page 7 of this information
    statement/proxy statement/prospectus.Q13:
    
    When do you expect the merger to be completed?A13:
    
    We are working on completing the merger as quickly as possible.
    To complete the merger, we must obtain the approval of the
    Horizon stockholders and satisfy or waive all other closing
    conditions under the merger agreement, which we currently expect
    should occur in the fourth quarter of 2007. However, we cannot
    assure you when or if the merger will occur. See The
    Merger Agreement  Conditions Precedent
    beginning on page 76 of this information statement/proxy
    statement/prospectus. If the merger occurs, we will promptly
    make a public announcement of this fact.Q14:
    
    What will happen to my Horizon shares after completion of the
    merger?A14:
    
    Upon completion of the merger, your shares of Horizon common
    stock will be canceled and will represent only the right to
    receive your portion of the merger consideration (or the fair
    value of your Horizon common stock if you seek appraisal rights)
    and any declared but unpaid dividends that you may be owed. In
    addition, trading in shares of Horizon common stock on the
    Nasdaq Global Market will cease and price quotations for shares
    of Horizon common stock will no longer be available. vii




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About the
    Special Meeting
  Q15:
    
    When and where is the Horizon special stockholder meeting?A15:
    
    The Horizon special stockholder meeting will take place
    on          ,
    2007, at 9:00 a.m., Central Time, and will be held
    at          ,
    Houston, Texas .Q16:
    
    What will happen at the special meeting?A16:
    
    At the Horizon special meeting, Horizon stockholders will vote
    on a proposal to approve and adopt the merger agreement and on a
    proposal to approve adjournments or postponements of the special
    meeting, if necessary, to permit further solicitation of proxies
    if there are not sufficient votes at the time of the special
    meeting to approve and adopt the merger proposal. We cannot
    complete the merger unless, among other things, Horizons
    stockholders vote to approve and adopt the merger agreement.Q17:
    
    Who is entitled to vote at the special meeting?A17:
    
    Only holders of record of Horizon common stock at the close of
    business
    on          ,
    2007, which is the date Horizons board of directors has
    fixed as the record date for the special meeting, are entitled
    to receive notice of and vote at the special meeting.Q18:
    
    What is a quorum?A18:
    
    A quorum is the number of shares that must be present to hold
    the meeting. The quorum requirement for the Horizon special
    meeting is the holders of a majority of the issued and
    outstanding shares of Horizon common stock as of the record
    date, present in person or represented by proxy and entitled to
    vote at the special meeting. A proxy submitted by a stockholder
    may indicate that all or a portion of the shares represented by
    the proxy are not being voted with respect to a particular
    matter. Proxies that are marked abstain or for which
    votes have otherwise been withheld and proxies relating to
    street name shares that are returned to the relevant
    company but not voted will be treated as shares present for
    purposes of determining the presence of a quorum on all matters.Q19:
    
    How many shares can vote?A19:
    
    On the record date, Horizon had
    outstanding           shares
    of common stock, which constitute Horizons only
    outstanding voting securities. Each Horizon stockholder is
    entitled to one vote on each proposal for each share of Horizon
    common stock held as of the record date.Q20:
    
    What vote is required?A20:
    
    The affirmative vote of the holders of a majority of the
    outstanding shares of Horizon common stock entitled to vote at
    the Horizon special meeting is required to adopt the merger
    agreement. The approval of a proposal to adjourn or postpone the
    special meeting, if necessary, to permit further solicitation of
    proxies, if there are not sufficient votes at the time of the
    special meeting to approve the other proposal(s), requires the
    vote of a majority of shares present in person or by proxy at
    the special meeting and actually voted at that special meeting.If a quorum is not present at the Horizon special meeting, the
    holders of a majority of the shares entitled to vote who are
    present in person or by proxy at the meeting may adjourn the
    meeting.Even if the votes set forth above are obtained at the special
    meeting, we cannot assure you that the merger will be completed,
    because the completion of the merger is subject to the
    satisfaction or waiver of other conditions discussed in this
    information statement/proxy statement/prospectus.Q21:
    
    What do I need to do now?A21:
    
    After carefully reading and considering the information
    contained and referred to in this information statement/proxy
    statement/prospectus, including its annexes, please authorize
    your shares of Horizon common stock to be voted by returning
    your completed, dated, and signed proxy card in the enclosed
    return envelope, or vote by telephone or Internet, as soon as
    possible. To be sure that your vote is counted, please submit
    your proxy as instructed on your proxy card even if you plan to
    attend the viii




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special meeting in person. DO NOT enclose or return your stock
    certificate(s) with your proxy card. If you hold shares
    registered in the name of a broker, bank, or other nominee, that
    broker, bank, or other nominee has enclosed or will provide a
    voting instruction card for use in directing your broker, bank,
    or other nominee how to vote those shares.Q22:
    
    May I vote in person?A22:
    
    Yes. You may attend the special meeting of Horizons
    stockholders and vote your shares in person rather than by
    signing and returning your proxy card. If you wish to vote in
    person and your shares are held by a broker, bank, or other
    nominee, you need to obtain a proxy from the broker, bank, or
    nominee authorizing you to vote your shares held in the
    brokers, banks, or nominees name.Q23:
    
    If my shares are held in street name, will my
    broker, bank, or other nominee vote my shares for me?A23:
    
    Yes, but your broker, bank, or other nominee may vote your
    shares of Horizon common stock only if you instruct your broker,
    bank, or other nominee how to vote. If you do not provide your
    broker, bank, or other nominee with instructions on how to vote
    your street name shares, your broker, bank, or other
    nominee will not be permitted to vote them on the merger
    agreement. You should follow the directions your broker, bank,
    or other nominee provides to ensure your shares are voted at the
    special meeting. Please check the voting form used by your
    broker, bank, or other nominee to see if it offers telephone or
    Internet voting.Q24:
    
    May I change my vote?A24:
    
    Yes. You may change your vote at any time before your proxy is
    voted at the special meeting. If your shares of Horizon common
    stock are registered in your own name, you can do this in one of
    three ways. First, you can deliver to Horizon, prior to the
    special meeting, a written notice stating that you want to
    revoke your proxy. The notice should be sent to the attention of
    William B. Gibbens, III, Secretary, Horizon Offshore, Inc.,
    2500 CityWest Boulevard, Suite 2200, Houston, Texas 77042,
    to arrive by the close of business
    on     , 2007. Second, prior to the special meeting, you can
    complete and deliver a new proxy card. The proxy card should be
    sent to the addressee indicated on the pre-addressed envelope
    enclosed with your initial proxy card to arrive by the close of
    business
    on          ,
    2007. The latest dated and signed proxy actually received by
    this addressee before the special meeting will be counted, and
    any earlier proxies will be considered revoked.If you vote your proxy electronically through the Internet or by
    telephone, you can change your vote by submitting a different
    vote through the Internet or by telephone, in which case your
    later-submitted proxy will be recorded and your earlier proxy
    revoked. Third, you can attend the Horizon special meeting
    and vote in person. Any earlier proxy will thereby be revoked
    automatically. Simply attending the special meeting, however,
    will not revoke your proxy, as you must vote at the special
    meeting to revoke a prior proxy.If you have instructed a broker to vote your shares, you must
    follow directions you receive from your broker to change or
    revoke your vote.If you are a street-name stockholder and you vote by proxy, you
    may later revoke your proxy instructions by informing the holder
    of record in accordance with that entitys procedures.Q25:
    
    How will the proxies vote on any other business brought up at
    the special meetings?A25:
    
    By submitting your proxy, you authorize the persons named on the
    proxy card to use their judgment to determine how to vote on any
    other matter properly brought before the special meeting. The
    proxies will vote your shares in accordance with your
    instructions. If you sign, date, and return your proxy without
    giving specific voting instructions, the proxies will vote your
    shares FOR the proposals. If you do ix




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not return your proxy, or if your shares are held in street name
    and you do not instruct your bank, broker or nominee on how to
    vote, your shares will not be voted at the special meeting.The board of directors of Horizon does not intend to bring any
    other business before the meeting, and it is not aware that
    anyone else intends to do so. If any other business properly
    comes before the meeting, it is the intention of the persons
    named on the proxy cards to vote as proxies in accordance with
    their best judgment.Q26:
    
    What is a broker non-vote?A26:
    
    A broker non-vote occurs when a bank, broker, or
    other nominee submits a proxy that indicates that the broker
    does not vote for some or all of the proposals, because the
    broker has not received instructions from the beneficial owners
    on how to vote on these proposals and does not have
    discretionary authority to vote in the absence of instructions.Q27:
    
    Will broker non-votes or abstentions affect the results?A27:
    
    If you are a Horizon stockholder, broker non-votes and
    abstentions will have the same effect as a vote against the
    proposal to adopt the merger agreement, but will have no effect
    on the outcome of the proposal relating to adjournments or
    postponements of the special meeting, if necessary, to permit
    further solicitation of proxies. If your shares are held in
    street name, we urge you to instruct your bank, broker, or
    nominee on how to vote your shares for those proposals on which
    you are entitled to vote.Q28:
    
    What happens if I choose not to submit a proxy or to vote?A28:
    
    If a Horizon stockholder does not submit a proxy or vote at the
    Horizon special meeting, it will have the same effect as a vote
    against the proposal to adopt the merger agreement, but will
    have no effect on the outcome of the proposal relating to
    adjournments or postponements of the special meeting, if
    necessary, to permit further solicitation of proxies.Q:29
    
    Why is it important for me to vote?A29:
    
    We cannot complete the merger without holders of a majority of
    the outstanding shares of Horizon common stock entitled to vote
    voting in favor of the approval and adoption of the merger
    agreement.Q30:
    
    What happens if I sell my shares of Horizon common stock
    before the special meeting?A30:
    
    The record date for the special meeting
    is          ,
    2007, which is earlier than the date of the special meeting. If
    you hold your shares of Horizon common stock on the record date
    you will retain your right to vote at the special meeting. If
    you transfer your shares of Horizon common stock after the
    record date but prior to the date on which the merger is
    completed, you will lose the right to receive the merger
    consideration for shares of Horizon common stock. The right to
    receive the merger consideration will pass to the person who
    owns your shares of Horizon common stock when the merger is
    completed.  General
  Q31:
    
    Should I send in my Horizon stock certificates now?A31:
    
    No. PLEASE DO NOT SEND ANY STOCK CERTIFICATES WITH YOUR
    PROXY CARD. After the merger is completed, you will receive
    written instructions informing you how to send in your stock
    certificates to receive the merger consideration.Q32:
    
    What does it mean if I get more than one proxy card?A32:
    
    Your shares are probably registered in more than one account.
    You should vote each proxy card you receive. x




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Q33:
    
    Where can I find more information about the special meeting,
    the merger, Horizon, or Cal Dive?A33:
    
    You can find more information about Horizon or Cal Dive in each
    of the companies respective filings with the Securities
    and Exchange Commission and, with respect to Cal Dive, with the
    New York Stock Exchange, and, with respect to Horizon, the
    Nasdaq Global Market. If you have any questions about the
    special meeting, the merger or how to submit your proxy, or if
    you need additional copies of this information statement/proxy
    statement/prospectus or the enclosed proxy card or voting
    instructions, you should contact Horizon at the address or phone
    number below. If your broker holds your shares, you can also
    call your broker for additional information.     (713) 361-2600
  xi




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SUMMARY  This summary highlights selected information from this
    information statement/proxy statement/prospectus, including
    material terms of the merger, and may not contain all of the
    information that is important to you. To understand the merger
    fully and for a more complete description of the legal terms of
    the merger, you should carefully read this entire document,
    including its Annexes, and the documents to which we refer you.
    See Where You Can Find More Information beginning on
    page 179 of this information statement/ proxy
    statement/prospectus.
 The
    Companies (page 79 for Cal Dive and page 127 for
    Horizon)  Cal Dive International, Inc.
   (281) 618-0400
    Horizon Offshore, Inc.
   (713) 361-2600
   The
    Merger (page 33)  General
      Merger
    Consideration (page 67)
 1




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Fractional
    Shares (page 67)
    Treatment
    of Horizon Stock Options and Restricted Stock
    (page 67)
     Risk
    Factors (page 7)   Material
    U.S. Federal Income Tax Consequences of the Merger to Horizon
    Stockholders (page 63)
 2




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Tax
    matters are very complicated and the tax consequences of the
    merger to any particular Horizon stockholder will depend on that
    stockholders particular situation. Horizon stockholders
    should consult their own tax advisor to determine the specific
    tax consequences of the merger to them.
 Recommendation
    of the Horizon Board of Directors (page 41)   Opinion
    of Lehman Brothers Inc.  Financial Advisor to Horizon
    (page 41)  Lehman Brothers opinion was provided for the use and
    benefit of Horizons board of directors in connection with
    its evaluation of the merger and does not address the merits of
    the proposed merger or constitute a recommendation to any
    stockholder as to how he or she should vote on the merger or any
    matter relevant to the merger agreement. The opinion addresses
    only the fairness, from a financial point of view, of the merger
    consideration to be received to Horizons stockholders, as
    of the date of the opinion.
 Ownership
    of Cal Dive Following the Merger   Board of
    Directors of Cal Dive Following the Merger   Market
    Prices and Share Information (page 29)
 3




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Closing Price per ShareJune 11, 2007


, 2007Cal Dive common stock

$
16.00


$Horizon common stock

$
16.95


$Merger consideration equivalent

$
19.25


$    Interests
    of Horizon Directors and Executive Officers in the Merger
    (page 60)   Conditions
    to Completion of the Merger (page 76)    
    absence of any temporary restraining order, preliminary or
    permanent injunction, or other order issued by a court of
    competent jurisdiction or other law, legal restraint, or
    prohibition having the effect of making the merger illegal or
    otherwise prohibiting the consummation of the merger;
    receipt of approvals and authorizations required under the
    antitrust laws, including expiration or early termination of the
    waiting period under the
    Hart-Scott-Rodino
    Act, to consummate the transactions contemplated by the merger
    agreement;
    approval for listing of the Cal Dive shares to be issued in
    the merger on the New York Stock Exchange, subject to official
    notice of issuance;
    continued effectiveness of the registration statement of which
    this information statement/proxy statement/prospectus is a part,
    the absence of a stop order by the Securities and Exchange
    Commission suspending the effectiveness of the registration
    statement and the absence of any continuing or threatened
    proceeding or investigation by the Securities and Exchange
    Commission to suspend such effectiveness;
    adoption of the merger agreement by the holders of a majority of
    the outstanding Horizon shares entitled to vote at the Horizon
    special meeting;
    accuracy as of the closing of the merger of the representations
    and warranties made by each of Cal Dive, Merger Sub, and
    Horizon to the extent specified in the merger agreement;
    Cal Dives, Merger Subs, and Horizons
    performance in all material respects of their respective
    covenants and agreements under the merger agreement; and
 4




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
    receipt of opinions by Cal Dive and Horizon from their
    respective tax counsel to the effect that the merger will
    constitute a reorganization within the meaning of
    Section 368(a) of the Code. Regulatory
    Matters (page 57)  Hart-Scott-Rodino Hart-Scott-Rodino
 Termination
    of the Merger Agreement (page 77)   Non
    Solicitation Provisions and Acquisition Proposals
    (page 72)   Fees and
    Expenses (page 78)
 5




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Accounting
    Treatment (page 57)   Comparison
    of Stockholders Rights (page 173)
 6




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RISK
    FACTORS  In addition to the other information included and
    incorporated by reference into this information statement/proxy
    statement/prospectus, including the matters addressed under the
    caption Cautionary Statement Regarding Forward-Looking
    Statements beginning on page 20, you should carefully
    read and consider the following risk factors in evaluating the
    proposals to be voted on at the special meeting of Horizon
    stockholders and in determining whether to vote for approval and
    adoption of the merger agreement. Please also refer to the
    additional risk factors identified in the periodic reports and
    other documents incorporated by reference into this information
    statement/proxy statement/prospectus and see Where You Can
    Find More Information beginning on page 179.
 Risks
    Relating to the Merger  The
    exchange ratio will not be adjusted in the event the value of
    Cal Dive common stock declines before the merger is completed.
    As a result, the value of the shares of Cal Dive common stock at
    the time that Horizon stockholders receive them could be less
    than the value of those shares today.
    The
    merger is subject to certain conditions to closing that, if not
    satisfied or waived, will result in the merger not being
    completed.
    Certain
    directors and the executive officers of Horizon have interests
    and arrangements that are different from, or in addition to,
    those of Horizons stockholders and that may influence or
    have influenced their decision to support or approve the
    merger.
   7




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##### Table of Contents




    the appointment of two of Horizons current directors to
    Cal Dives board of directors, one of whom also serves
    as an executive officer;
    it is expected that all of Horizons executive
    officers employment will terminate as a result of the
    merger, and under the terms of employment agreements entered
    into between Horizon and its executive officers, those officers
    are entitled to certain specified severance benefits;
    as of the effective time of the merger, acceleration of vesting
    of Horizon stock options and restricted stock for directors and
    executive officers;
    indemnification of directors and executive officers of Horizon
    against certain liabilities arising both before and, in some
    cases, after the merger; and
    liability insurance for directors and executive officers of
    Horizon.    Cal
    Dive may face difficulties in achieving the expected benefits of
    the merger.
    Cal
    Dives actual financial position and results of operations
    may differ significantly and adversely from the pro forma
    amounts included in this information statement/proxy
    statement/prospectus.
    Horizon
    will be subject to business uncertainties and contractual
    restrictions while the merger is pending.
   8




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The
    merger agreement limits Horizons ability to pursue
    alternatives to the merger.
      Failure
    to complete the merger could negatively impact the stock price
    and the future business and financial results of
    Horizon.
    
    Horizon may be required to pay Cal Dive a termination fee
    of $18.9 million if the merger agreement is terminated
    under certain circumstances and Horizon enters into or completes
    an alternative transaction;
    The current market price of Horizon common stock may reflect a
    market assumption that the merger will occur, and a failure to
    complete the merger could result in a negative perception by the
    stock market of Horizon generally and a resulting decline in the
    market price of Horizon common stock;
    Certain costs relating to the merger (such as legal, accounting,
    and financial advisory fees) are payable by Horizon whether or
    not the merger is completed;
    There may be substantial disruption to the business of Horizon
    and a distraction of its management and employees from
    day-to-day operations, because matters related to the merger
    (including integration planning) may require substantial
    commitments of time and resources, which could otherwise have
    been devoted to other opportunities that could have been
    beneficial to Horizon;
    Horizons business could be adversely affected if it is
    unable to retain key employees or attract qualified
    replacements; and
    Horizon would continue to face the risks that it currently faces
    as an independent company, as further described in the documents
    that Horizon has filed with the SEC that are incorporated by
    reference into this information statement/proxy
    statement/prospectus. 9




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The
    price of Cal Dive common stock may be affected by factors
    different from those affecting the price of Horizon common
    stock.
  Form 10-K
  Cal
    Dive will have higher levels of indebtedness following the
    merger than either Cal Dive or Horizon had before the
    merger.
    
    limiting its ability to obtain additional financing on
    satisfactory terms to fund its working capital requirements,
    capital expenditures, acquisitions, investments, debt service
    requirements, and other general corporate requirements;
    increasing its vulnerability to general economic downturns,
    competition, and industry conditions, which could place it at a
    competitive disadvantage compared to its competitors that are
    less leveraged;
    increasing its exposure to rising interest rates because a
    portion of its borrowings will be at variable interest rates;
    reducing the availability of its cash flow to fund its working
    capital requirements, capital expenditures, acquisitions,
    investments, and other general corporate requirements because it
    will be required to use a substantial portion of its cash flow
    to service debt obligations; and
    limiting its flexibility in planning for, or reacting to,
    changes in its business and the industry in which it operates.   10




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The
    opinion obtained by Horizon from its financial advisor does not
    reflect changes in circumstances between signing the merger
    agreement and the completion of the merger.
    The
    shares of Cal Dive common stock to be received by Horizon
    stockholders as a result of the merger will have different
    rights from the shares of Horizon common stock.
    Helix
    will continue to control Cal Dive and Horizon stockholders will
    exercise less influence over management.
    The
    merger may be completed even though Cal Dive or Horizon suffers
    a material adverse change.
    
    changes in laws, rules or regulations applicable to
    Cal Dive or Horizon;
    changes in general regulatory or economic conditions in the
    United States or other countries in which Cal Dive or
    Horizon operate;
    changes in, or events or conditions generally affecting, the
    industries in which Cal Dive and Horizon operate;
    changes in the market price of oil or natural gas;
    changes in the market price of Cal Dives or
    Horizons common stock; or
    any changes or effects arising out of the negotiation, public
    announcement or pending nature of the merger. 11




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Risks
    Relating to Cal Dive  Cal
    Dives business largely depends on offshore exploration,
    development, and production activity in the oil and natural gas
    industry, which is currently at a historically high level and
    could decline in the future.
    
    changes in United States and international economic conditions;
    demand for oil and natural gas, especially in the United States,
    China, and India;
    worldwide political conditions, particularly in significant
    oil-producing regions such as the Middle East, West Africa, and
    Latin America;
    actions taken by the Organization of Petroleum Exporting
    Countries, or OPEC;
    the availability and discovery rate of new oil and natural gas
    reserves in offshore areas;
    the cost of offshore exploration for, and production and
    transportation of, oil and natural gas;
    the ability of oil and natural gas companies to generate funds
    or otherwise obtain external capital for exploration,
    development, and production operations;
    the sale and expiration dates of offshore leases in the United
    States and overseas;
    technological advances affecting energy exploration, production,
    transportation, and consumption;
    weather conditions;
    environmental or other government regulations; and
    tax policies.    Market
    conditions in the marine contracting industry are highly
    cyclical and subject to rapid change. Due to the short-term
    nature of most of Cal Dives contracts, adverse changes in
    market conditions can have an immediate impact on Cal
    Dives results of operations.
   12




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##### Table of Contents



Cal
    Dives business is concentrated on the Gulf of Mexico OCS,
    and the mature nature of this region could result in less
    exploration, development, and production activities in the area,
    thereby reducing demand for Cal Dives
    services.
    Intense
    competition in Cal Dives industry may reduce its
    profitability and weaken its financial condition.
    If Cal
    Dive fails to manage its growth effectively, its results of
    operations could be harmed.
      
    incorrect assumptions regarding the future results of acquired
    operations or assets or expected cost reductions or other
    synergies expected to be realized as a result of acquiring
    operations or assets;
    failure to integrate the operations or management of any
    acquired operations or assets successfully and timely;
    diversion of managements attention from existing
    operations or other priorities; and
    Cal Dives inability to secure, on terms it finds
    acceptable, sufficient financing that may be required for any
    such acquisition or investment.   13




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##### Table of Contents



Cal
    Dives operations outside of the United States are subject
    to additional political, economic, and other uncertainties that
    could adversely affect its business, financial condition, or
    results of operations, and its exposure to such risks will
    increase as it expands its international
    operations.
    
    political, social, and economic instability;
    the loss of revenue, property, and equipment from hazards such
    as expropriation, nationalization, war, insurrection, acts of
    terrorism, and other political risks;
    increased operating costs;
    increases in taxes and governmental royalties;
    renegotiation or abrogation of contracts with governmental
    entities;
    changes in laws and policies governing operations of
    foreign-based companies;
    import-export quotas;
    currency restrictions and exchange rate fluctuations;
    world economic cycles;
    limited market access; and
    other uncertainties arising out of foreign government
    sovereignty over our international operations.      Cal
    Dive is the subject of an agreed final judgment that prevents it
    from making acquisitions of certain saturation diving systems
    without the consent of the U.S. Department of Justice, which
    could adversely affect its ability to make strategic
    acquisitions and increase its revenues and
    profitability.
    The
    loss of the services of one or more of Cal Dives key
    employees, or its failure to attract and retain other highly
    qualified personnel in the future, could disrupt its operations
    and adversely affect its financial results.
   14




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##### Table of Contents



The
    operation of marine vessels is risky, and Cal Dive may incur
    losses or other liabilities that are not covered by insurance
    and could have a material adverse effect on its financial
    condition and results of operations.
    Cal
    Dive has substantial debt obligations that could restrict its
    operations and impair its financial condition.
      
    increasing its vulnerability to adverse economic, regulatory,
    and industry conditions;
    limiting its ability to compete and its flexibility in planning
    for, or reacting to, changes in its business and the industry;
    limiting its ability to borrow additional funds; and
    requiring it to dedicate a substantial portion of its cash flow
    from operations to payments on its debt, thereby reducing funds
    available for working capital, capital expenditures,
    acquisitions, and other purposes.   15




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Cal
    Dives contracting business declines in winter, and adverse
    weather conditions in the Gulf of Mexico can adversely affect
    its revenues.
    Cal
    Dives original estimates of the costs associated with its
    qualified turnkey projects and capital projects may be incorrect
    and result in reduced profitability, losses, or cost over-runs
    on those projects.
    Cal
    Dive is subject to extensive federal, state, local, and other
    laws and regulations that could adversely affect the cost,
    manner, or feasibility of conducting its
    operations.
    Cal
    Dive may incur substantial costs and liabilities with respect to
    environmental, health, and safety laws and
    regulations.
   16




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##### Table of Contents



Cal
    Dive has a limited operating history as an independent company
    and its historical financial information is not necessarily
    representative of the results it would have achieved as an
    independent publicly traded company and may not be a reliable
    indicator of its future results.
    
    Cal Dives historical financial results reflect
    allocations of corporate expenses from Helix. Those allocations
    may be different from the comparable expenses it would have
    incurred had it operated as an independent publicly traded
    company.
    Cal Dives working capital requirements and funding
    for maintenance capital expenditures, strategic investments, and
    acquisitions have historically been part of the corporate-wide
    cash management program of Helix. Following Cal Dives
    initial public offering in December 2006, it has been solely
    responsible for the provision of funds to finance its working
    capital and other cash requirements.  Helix
    owns a controlling interest in Cal Dive and will continue to own
    a controlling interest of Cal Dive after the merger. The
    interests of Helix may conflict with those of Cal Dives
    other stockholders, and other stockholders voting power
    may be limited.
     17




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##### Table of Contents



Conflicts
    of interest may arise between Helix and Cal Dive that could be
    resolved in a manner unfavorable to Cal Dive.
      
    Cross officerships, directorships, and stock
    ownership.  The ownership interests of
    Cal Dives directors or executive officers in the
    common stock of Helix or service as a director or officer of
    both Helix and Cal Dive could create, or appear to create,
    conflicts of interest when directors and executive officers are
    faced with decisions that could have different implications for
    the two companies. For example, these decisions could relate to
    (i) the nature, quality, and cost of services rendered to
    Cal Dive by Helix, (ii) disagreement over the
    desirability of a potential acquisition or other corporate
    opportunity, (iii) employee retention or recruiting, or
    (iv) Cal Dives dividend policy.
    Intercompany transactions.  From time to time,
    Helix or its affiliates may enter into transactions with
    Cal Dive or its subsidiaries or other affiliates. Although
    the terms of any such transactions will be established based
    upon negotiations between employees of Helix and Cal Dive
    and, when appropriate, subject to the approval of the
    independent directors on Cal Dives board or a
    committee of disinterested directors, the terms of any such
    transactions may not be as favorable to Cal Dive or its
    subsidiaries or affiliates as may otherwise be obtained in
    arms length negotiations. Under the Master Agreement, at
    Helixs request, Cal Dive will continue to contract
    vessels and related equipment owned by Cal Dive to Helix,
    at prevailing market rates.
    Intercompany agreements.  Cal Dive has
    entered into certain agreements with Helix pursuant to which
    Helix has agreed to provide Cal Dive with certain
    accounting, tax, and other services and Cal Dive has agreed
    to provide Helix with certain training, supply chain,
    operational facilities, and operational human resources
    services. Payments for these services will allow Helix and
    Cal Dive to fully recover the allocated direct costs of
    providing the services, plus all out-of-pocket costs and
    expenses. In addition, Cal Dive has entered into a number
    of intercompany agreements covering matters such as tax sharing
    and Cal Dives responsibility for certain liabilities
    previously undertaken by Helix for certain of its businesses.
    Cal Dive negotiated the terms of these agreements with
    Helix in the context of a parent-subsidiary relationship. The
    terms were not the result of arms length negotiations. In
    addition, conflicts could arise in the interpretations of any
    extension or renegotiation of these agreements in the future.  If
    Helix engages in the same type of business Cal Dive conducts or
    takes advantage of business opportunities that might be
    attractive to Cal Dive, Cal Dives ability to operate
    successfully and expand its business may be
    hampered.
    
    engaging in the same or similar business activities or lines of
    business as Cal Dive, or
    doing business with any of Cal Dives clients,
    customers, or vendors. 18




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##### Table of Contents



Future
    sales or distributions of Cal Dives shares by Helix could
    depress the market price for shares of Cal Dive common
    stock.
    Cal
    Dive will not have control over certain tax decisions and could
    be liable for income taxes owed by Helix.
     19




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##### Table of Contents



Cal
    Dive could be responsible for taxes resulting from the transfer
    of assets to it by Helix.
    Cal
    Dives stock ownership by Helix, provisions in Cal
    Dives agreements with Helix, and Cal Dives corporate
    governance documents and Delaware law may delay or prevent an
    acquisition of Cal Dive that its other stockholders may consider
    favorable.
    Conflicts
    of interest may arise due to the vesting schedule of grants of
    restricted stock to Cal Dives executive
    officers.
   CAUTIONARY
    STATEMENT REGARDING FORWARD-LOOKING STATEMENTS    /
 20




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##### Table of Contents




    the factors described under Risk Factors beginning
    on page 7 of this information statement/proxy
    statement/prospectus;
    the factors that generally affect Cal Dives and
    Horizons businesses as further outlined in
    Managements Discussion and Analysis of Financial
    Condition and Results of Operations included in this
    information statement/proxy statement/prospectus, in the case of
    Cal Dive, and in Horizons Annual Report on
    Form 10-K
    for the year ended December 31, 2006 and Quarterly Report
    on
    Form 10-Q
    for the quarter ended June 30, 2007, in the case of
    Horizon, and elsewhere in this information statement/proxy
    statement/prospectus, including the performance of contracts by
    suppliers, customers and partners, employee management issues,
    and complexities of global political and economic
    developments; and
    the fact that, following the merger, the actual results of the
    combined company could differ materially from the expectations
    set forth in this information statement/proxy
    statement/prospectus and the documents incorporated by reference
    depending on additional factors such as:  
    the combined companys cost of capital;
    the ability of the combined company to identify and implement
    cost savings, synergies, and efficiencies in the time frame
    needed to achieve these expectations;
    the combined companys actual capital needs, the absence of
    any material incident of property damage or other hazard that
    could affect the need to effect capital expenditures, and any
    currently unforeseen merger or acquisition opportunities that
    could affect capital needs; and
    the costs incurred in implementing synergies including, but not
    limited to, our ability to terminate, amend, or renegotiate
    prior contractual commitments of Cal Dive and Horizon.   21




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SELECTED
    HISTORICAL AND UNAUDITED PRO FORMA FINANCIAL
    INFORMATION Selected
    Cal Dive Historical Financial Data      DLB801 Kestrel
   22




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##### Table of Contents



Six MonthsYear Ended December 31,


Ended June 30,2006


2005


2004


2003


2002


2007


2006(Unaudited)


(Unaudited)


(Unaudited)(In thousands, except per share and marine contracting
    activity data)Results of Operations
    Data:Net revenues

$
509,917


$
224,299


$
125,786


$
135,488


$
139,887


$
284,484


$
244,554Cost of Sales


287,387



152,586



101,583



108,479



116,167



180,967



133,405Gross Profit


222,530



71,713



24,203



27,009



23,720



103,517



111,149Gain on sale of assets


349



270















1,694



283Selling and administrative expenses


37,431



16,730



12,318



10,337



8,055



20,766



15,515Income from operations


185,448



55,253



11,885



16,672



15,665



84,445



95,917Equity in earnings (losses) of
    investment, inclusive of impairment charge


(487
)


2,817















(10,841
)


2,650Net interest income (expense)


163



45















(4,958
)


316Income before income taxes


185,124



58,115



11,885



16,672



15,665



68,646



98,883Provision for income taxes


65,710



20,385



4,211



5,870



5,510



27,018



34,689Net income

$
119,414


$
37,730


$
7,674


$
10,802


$
10,155


$
41,628


$
64,194Net income per common share
    (unaudited)Basic

$
1.91


$
0.61
(1)

$
0.12
(1)

$
0.18
(1)

$
0.17
(1)

$
0.50


$
1.04
(1)Diluted

$
1.91


$
0.61
(1)

$
0.12
(1)

$
0.18
(1)

$
0.17
(1)

$
0.50


$
1.04
(1)Other Financial Data:Depreciation and amortization

$
24,515


$
15,308


$
15,510


$
15,209


$
14,193


$
18,074


$
10,727Capital expenditures


38,086



36,407



2,912



2,784



12,980



12,272



7,387Acquisition of business


100,128



42,917



















78,174Dividends paid to Helix


464,401























Cash Flow Data(2)Cash flows provided by (used in)Operating activities

$
86,439


$
32,228


$
28,610


$
26,370


$
15,691


$
53,767


$
47,022Investing activities


(121,157
)


(79,547
)


(2,912
)


(2,584
)


(4,310
)


(11,755
)


(68,779
)Financing activities


57,373



47,319



(25,698
)


(23,786
)


(11,381
)


(61,000
)


21,761Marine ContractingActivity Data
    (unaudited):Number of vessels(3)


25



22



13



13



13



25



24Utilization(4)


91
%


79
%


63
%


68
%


61
%


76
%


97
%   December 31,


June 30,2006


2005


2004


2003


2002


2007(Unaudited)


(Unaudited)


(Unaudited)(In thousands)Balance Sheet Data:Total current assets

$
168,747


$
110,484


$
46,565


$
43,270


$
52,556


$
153,390Net property and equipment


222,247



113,604



76,329



91,533



100,605



226,035Total assets


452,153



277,884



144,817



156,280



172,904



445,608Total current liabilities


58,814



73,869



27,438



21,165



28,431



65,318Total liabilities


294,392



100,101



52,309



45,748



49,388



244,616Long-term debt


201,000



















140,000Total stockholders equity


157,761



177,783



92,508



110,532



123,516



200,992  23




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##### Table of Contents



(1)
    
    Basic and diluted net income per share for these periods are
    based upon 61,506,691 shares, reflecting a 61,506.691 to 1
    stock split effected immediately prior to Cal Dives
    initial public offering.(2)
    
    For all periods through December 14, 2006: (i) cash
    flows from financing activities have been reflected as
    (a) cash transfers from Cal Dive to Helix equal to
    substantially all cash provided by operating activities and
    (b) cash transfers from Helix to Cal Dive equal to the
    amount of cash used in investing activities,
    (ii) substantially all excess cash has been transferred to
    Cal Dives owner, and (iii) these cash transfers have
    been reflected as changes in total stockholders equity.(3)
    
    As of the end of the period and excluding acquired vessels prior
    to their in-service dates, vessels taken out of service prior to
    their disposition and vessels jointly owned by a third party.(4)
    
    Average vessel utilization is calculated by dividing the total
    number of days the vessels generated revenues by the total
    number of days the vessels were available for operation in each
    period and does not reflect acquired vessels prior to their
    in-service dates, vessels in drydocking, vessels taken out of
    service for upgrades or prior to their disposition and vessels
    jointly owned by a third party. 24




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Selected
    Horizon Historical Financial Data    Six MonthsYear Ended December 31,


Ended June 30,2006


2005


2004


2003


2002


2007


2006(Unaudited)


(Unaudited)(In thousands, except per share data)Income Statement
    Data:Contract revenues

$
547,289


$
325,044


$
254,209


$
270,313


$
283,410


$
204,066


$
286,885Cost of contract revenues


400,040



268,280



226,391



263,812



253,016



189,958



209,208Gross profit


147,249



56,764



27,818



6,501



30,394



14,108



77,677Selling, general and
    administrative expenses


33,167



30,922



30,687



21,749



21,845



16,096



17,323Gain on insurance settlement


(14,300
)






















(14,300
)Reserve for claims and receivables


18,458



1,711



5,692



33,092











18,458Impairment of property, equipment
    and intangibles


100







22,361



21,332



9,852







Impairment loss on assets held for
    sale






2,261



3,268















Operating income (loss)


109,824



21,870



(34,190
)


(69,672
)


(1,303
)


(1,988
)


56,196Other:Interest expense, net of amount
    capitalized


(13,989
)


(67,572
)


(25,995
)


(9,542
)


(4,585
)


(5,705
)


(7,625
)Interest income


2,967



777



286



67



91



1,768



792Loss on debt extinguishment


(2,402
)


(23,138
)


(1,719
)


(868
)










(2,402
)Other income (expense), net


25



53



152



(88
)


(2,831
)


15



(37
)Income (loss) before income taxes


96,425



(68,010
)


(61,466
)


(80,103
)


(8,628
)


(5,910
)


46,924Income tax provision (benefit)


29,415



3,046



2,103



(7,599
)


(3,079
)


(1,944
)


14,583Net income (loss)

$
67,010


$
(71,056
)

$
(63,569
)

$
(72,504
)

$
(5,549
)

$
(3,966
)

$
32,341Net income (loss) per
    share  basic

$
2.18


$
(16.09
)

$
(51.45
)

$
(68.58
)

$
(5.42
)

$
(0.12
)

$
1.09Net income (loss) per
    share  diluted

$
2.14


$
(16.09
)

$
(51.45
)

$
(68.58
)

$
(5.42
)

$
(0.12
)

$
1.06   25




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##### Table of Contents



Six MonthsYear Ended December 31,


Ended June 30,2006


2005


2004


2003


2002


2007


2006(Unaudited)


(Unaudited)(In thousands, except per share data)Statement of Cash Flow
    Data:Net cash provided by (used in)
    operating activities

$
52,059


$
(2,338
)

$
2,095


$
(53,065
)

$
48,487


$
21,118


$
4,929Net cash provided by (used in)
    investing activities


(4,550
)


4,478



(4,776
)


(14,683
)


(59,752
)


(28,494
)


(15,725
)Net cash provided by (used in)
    financing activities


6,421



2,845



30,541



71,790



9,474



(7,654
)


24,888   December 31,


June 30,2006


2005


2004


2003


2002


2007(Unaudited)(In thousands)Balance Sheet Data:Working capital

$
204,523


$
74,119


$
29,022


$
26,107


$
30,385


$
171,807Total assets


523,019



402,721



394,277



409,541



420,533



551,232Long-term debt, net of current
    maturities


99,399



103,979



170,347



146,886



90,062



93,283  26




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Selected
    Unaudited Condensed Combined Pro Forma Financial Data  Form 10-K Form 10-Q
  Year Ended


Six Months EndedDecember 31, 2006


June 30, 2007(In thousands, except per share amounts)Statement of Operations
    data:Net revenues and other income

$
1,040,978


$
479,941Net income


175,349



28,278Net income applicable to common
    stockholders


175,349



28,278Earnings per common share:Basic

$
2.11


$
0.27Diluted

$
2.11


$
0.27   As ofJune 30, 2007(In thousands)Balance Sheet data:Total assets

$
1,305,894Long-term debt


474,573Stockholders equity


525,108  27




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COMPARATIVE
    HISTORICAL AND PRO FORMA PER SHARE INFORMATION      Form 10-K Form 10-Q
      Six MonthsEnded


Year EndedJune 30, 2007


December 31, 2006Cal Dive historicalNet income applicable to common
    stockholders  basic

$
0.50


$
1.91Net income applicable to common
    stockholders  diluted

$
0.50


$
1.91Cash dividends(2)

$



$
Book value at end of period

$
2.38


$
1.87Cal Dive pro forma
    combinedNet income applicable to common
    stockholders  basic

$
0.27


$
2.11Net income applicable to common
    stockholders  diluted

$
0.27


$
2.11Cash dividends

$



$
Book value at end of period

$
5.04


$
4.60Horizon historicalNet income applicable to common
    stockholders  basic

$
(0.12
)

$
2.18Net income applicable to common
    stockholders  diluted

$
(0.12
)

$
2.14Cash dividends

$



$
Book value at end of period

$
9.02


$
9.18Horizon pro forma combined
    (equivalent)(1)Net income applicable to common
    stockholders  basic

$
0.17


$
1.32Net income applicable to common
    stockholders  diluted

$
0.17


$
1.32Cash dividends

$



$
Book value at end of period

$
3.15


$
2.88  28




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##### Table of Contents



(1)
    
    Does not reflect the $9.25 in cash per share of Horizon common
    stock to be received as part of the merger consideration.(2)
    
    In connection with the Cal Dive initial public offering in
    December 2006, total dividends paid to Helix were
    $464 million. COMPARATIVE
    MARKET VALUE INFORMATION        Closing Priceper ShareJune 11,2007


, 2007Cal Dive common stock

$
16.00


$Horizon common stock

$
16.95


$Merger consideration equivalent

$
19.25


$  STOCKHOLDER
    LITIGATION  Edward Fritsche ex rel. Horizon
    Offshore, Inc. v. John T. Mills, et al. No. 2007-35288 Edith Olanoff ex rel.
    Horizon Offshore, Inc. v. John T. Mills, et al. No. 2007-36084 Fritsche
 29




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##### Table of Contents



INFORMATION
    ABOUT THE SPECIAL MEETING AND VOTING   Date,
    Time and Place   Matters
    to Be Considered    
    to consider and vote upon a proposal to approve and adopt the
    merger agreement;
    to consider and vote upon a proposal to adjourn or postpone the
    special meeting, if necessary, to solicit additional proxies in
    favor of the approval and adoption of the merger
    agreement; and
    to consider and transact any other business as may properly be
    brought before the special meeting or any adjournments or
    postponements thereof.   Stockholders
    Entitled to Vote     Quorum
    and Required Vote       30




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How
    Shares Will Be Voted at the Special Meeting         How to
    Vote Your Shares         31




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##### Table of Contents



How to
    Change Your Vote    
    completing, signing, and timely submitting a new proxy to the
    addressee indicated on the pre-addressed envelope enclosed with
    your initial proxy card by the close of business
    on          ,
    2007; the latest dated and signed proxy actually received by
    such addressee before the special meeting will be counted, and
    any earlier proxies will be considered revoked;
    notifying Horizons Secretary, at 2500 CityWest Boulevard,
    Suite 2200, Houston, Texas 77042, in writing, by the close
    of business on , 2007, that you have revoked your earlier
    proxy; or
    voting in person at the special meeting.     Voting by
    Participants in the Horizon Benefit Plans   Solicitation
    of Proxies     Recommendation
    of the Horizon Board of Directors   Special
    Meeting Admission   32




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##### Table of Contents



PLEASE DO NOT SEND IN ANY HORIZON COMMON STOCK CERTIFICATES
    WITH YOUR PROXY CARD. After the merger is completed, you will
    receive written instructions from the exchange agent informing
    you how to surrender your stock certificates to receive the
    merger consideration.
 Adjournment
    and Postponements   THE
    MERGER General     Background
    of the Merger     33




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90-day
 34




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March 9-15,
         35




---



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36




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37




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mid-day
         38




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Horizons
    Reasons for the Merger      
    the merger will provide Horizons stockholders with an
    opportunity to participate in the ownership of a larger,
    financially stronger company that is expected to be better
    positioned to respond to opportunities and developments in the
    marine construction industry in which efficiency and global
    competitiveness 39




---



##### Table of Contents



are increasingly of critical importance while still providing
    immediate value through the cash component of the merger
    consideration;  
    the boards belief that the combined company would be a
    leader in the marine construction industry, stronger both
    operationally and financially, with the ability to compete for
    large international construction projects, better able to meet
    changing customer needs, compete more effectively in an
    increasingly global market, and deliver increased value to its
    stockholders;
    the boards belief that the combined company would have a
    more efficient operating platform with a greater scope of
    complementary marine construction and diving support services,
    as compared to Horizon on a stand-alone basis, providing
    significant opportunities for more efficient project execution,
    performance and operation;
    the opinion provided by Lehman Brothers dated June 11,
    2007, to the effect that, as of the date of the opinion and
    based upon the procedures followed, assumptions made, matters
    considered and limitations on the scope of review set forth in
    the opinions, the merger consideration was fair, from a
    financial point of view, to the holders of Horizon common stock
    (the full text of the written opinion of Lehman Brothers setting
    forth the procedures followed, assumptions made, matters
    considered and limitations on the scope of review in connection
    with the opinions is attached as Annex B to this document);
    the current economic, industry and market trends affecting each
    of Horizon and Cal Dave, including those which favor efficient
    consolidation to improve domestic and global competitiveness, as
    well as anticipated operating efficiencies and potential
    synergies from the merger;
    the current and historical trading prices of Horizon and
    Cal Dive common stock;
    the proposed composition of the combined companies board
    of directors, including the fact that David Sharp,
    President and Chief Executive Officer of Horizon, and John
    Mills, Chairman of the Board, would join Cal Dives
    board of directors, thereby ensuring that Cal Dives
    board consisted of a majority of independent directors;
    Horizon could during the
    45-day
    go-shop period actively solicit alternative
    transaction proposals, enter into discussions with third parties
    regarding any such proposals and terminate the merger agreement
    in order to enter into a transaction with a third party on terms
    more favorable to Horizons stockholders, upon the payment
    to Cal Dive of a termination fee equal to 1.5% of the
    merger consideration ($9.4 million); and
    the review and analysis of each of Horizons and
    Cal Dives business, financial condition, earnings,
    risks and prospects.  45-day
    
    the risk that the anticipated cost efficiencies and potential
    synergies will not be achieved in the expected time frame or at
    all;
    the problems inherent in combining the operations of two large
    companies, including the possibility that management may be
    distracted from regular business concerns by the need to
    integrate operations, unforeseen difficulties in integrating
    operations and systems, problems assimilating and retaining
    employees and potential adverse short-term effects on operating
    results of the combined company; 40




---



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
    the timing of receipt and the terms of approvals and actions
    from relevant governmental and regulatory authorities, including
    the possibility of delay in obtaining satisfactory approvals or
    the imposition of unfavorable terms, conditions or concessions
    on the approvals;
    Cal Dive will continue to be controlled by Helix and
    subject to the risks arising as a result set forth under
    Risk Factors  Risks Relating to
    Cal Dive; and
    the interests that certain Horizon executive officers and
    directors may have with respect to the merger in addition to
    their interests as Horizon stockholders.     Recommendation
    of the Horizon Board of Directors    FOR THE REASONS SET FORTH ABOVE, THE BOARD OF DIRECTORS OF
    HORIZON HAS UNANIMOUSLY ADOPTED THE MERGER AGREEMENT AS BEING IN
    THE BEST INTERESTS OF HORIZON AND ITS STOCKHOLDERS, AND
    UNANIMOUSLY RECOMMENDS THAT HORIZONS STOCKHOLDERS VOTE FOR
    THE APPROVAL AND ADOPTION OF THE MERGER AGREEMENT.
 Opinion
    of Lehman Brothers Inc.  Financial Advisor to
    Horizon    The full text of Lehman Brothers opinion dated
    June 11, 2007, is included as Annex B to this
    information statement/proxy statement/prospectus and is
    incorporated herein by reference. Holders of Horizons
    common stock should read Lehman Brothers opinion letter in
    its entirety for a discussion of the procedures followed,
    factors considered, assumptions made and qualifications and
    limitations of the review undertaken by Lehman Brothers in
    connection with its opinion. This summary of the Lehman Brothers
    opinion is qualified in its entirety by reference to the full
    text of the opinion.
  Lehman Brothers advisory services and opinion were
    provided for the information and assistance of the board of
    directors of Horizon in connection with its consideration of the
    proposed transaction. Lehman Brothers opinion was limited
    solely to the fairness of the merger consideration. Lehman
    Brothers opinion is not intended to be and does not
    constitute a recommendation to any stockholder as to how that
    stockholder should vote or act with respect to the proposed
    merger or any other matter described in this information
    statement/proxy statement/prospectus. Lehman Brothers was not
    requested to consider, and its opinion does not address, the
    relative merits of the merger compared to any alternative
    business strategies that might exist for Horizon or the effect
    of any other transaction in which Horizon might engage.
 41




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
    the merger agreement and the specific terms of the merger;
    such publicly available information concerning Horizon and
    Cal Dive that Lehman Brothers believed to be relevant to
    its analysis, including, without limitation, the Annual Reports
    on
    Form 10-K
    for the year ended December 31, 2006 and the Quarterly
    Reports on
    Form 10-Q
    for the quarter ended March 31, 2007 for each of Horizon
    and Cal Dive;
    financial and operating information with respect to the
    business, operations and prospects of Horizon furnished to us by
    Horizon, including financial projections of Horizon prepared by
    management of Horizon;
    financial and operating information with respect to the
    business, operations and prospects of Cal Dive furnished to
    us by Cal Dive, including financial projections of
    Cal Dive prepared by the management of Cal Dive;
    the trading histories of Horizon common stock from June 9,
    2006 to June 8, 2007 and Cal Dive common stock from
    December 13, 2006 (the date of Cal Dives initial
    public offering) to June 8, 2007, and a comparison of those
    trading histories with each other and with those of other
    companies that Lehman Brothers deemed relevant;
    a comparison of the historical financial results and present
    financial condition of Horizon and Cal Dive with each other
    and with those of other companies that Lehman Brothers deemed
    relevant;
    a comparison of the financial terms of the merger with the
    financial terms of certain other transactions that Lehman
    Brothers deemed relevant;
    the potential pro forma impacts of the merger on the current and
    future financial performance of the combined company; including
    the amounts and timing of the cost savings and operating
    synergies expected to result from the Proposed Transaction;
    published estimates by independent equity research analysts with
    respect to the future financial performance of Horizon and
    Cal Dive; and
    the relative contributions of Horizon and Cal Dive to the
    current and future financial performance of the combined company
    on a pro forma basis.       42




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Valuation
    Analysis Used to Compare to Merger Consideration
    This table should be read together with the more
    detailed descriptions set forth below.
 43




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Summary
    of Horizon Offshore Valuation Analysis
  Summary Description of

Implied EquityValuation Methodology

Valuation Methodology

Value per ShareComparable Company Analysis

Market valuation benchmark based
    on trading multiples of selected comparable companies for
    selected financial and asset-based measures

$13.00 - $22.50Comparable Transactions Analysis

Market valuation benchmark based
    on consideration paid in selected comparable transactions

$13.86 - $22.27Discounted Cash Flow Analysis

Net present valuation of
    management projections of after-tax cash flows assuming selected
    discount rates and terminal value multiples Case I: Growth Case

$20.40 - $26.87 Case II: Base Case

$14.56 - $18.48 Case III: Downside Case

$10.62 - $13.48Premium Analysis

Market valuation based on
    comparable corporate transactions to calculate the premiums paid
    by the acquirers to the acquired companys stockholders

$18.59 - $21.97Research Price Target Analysis

Market valuation based on equity
    research analysts current price targets

$14.25 - $23.00Nominal Merger Consideration to be
    Paid by Cal Dive in the Merger (Based on Cal Dive Stock Price as
    of June 8, 2007)



$19.23  44




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##### Table of Contents



Summary
    of Cal Dive International Valuation Analysis
  Summary Description of

Implied EquityValuation Methodology

Valuation Methodology

Value per ShareComparable Company Analysis

Market valuation benchmark based
    on trading multiples of selected comparable companies for
    selected financial and asset-based measures

$11.50 - $20.50Comparable Transactions Analysis

Market valuation benchmark based
    on consideration paid in selected comparable transactions

$ 9.92 - $15.80Discounted Cash Flow Analysis

Net present valuation of
    management projections of after-tax cash flows assuming selected
    discount rates and terminal value multiples Case I: Growth Case

$17.12 - $23.39 Case II: Base Case

$13.62 - $17.86 Case III: Downside Case

$ 9.00 - $11.98Research Price Target Analysis

Market valuation based on equity
    research analysts current price targets

$15.00 - $18.00Cal Dive Stock Price as of
    June 8, 2007



$15.96   Comparable
    Company Analysis
    
    Cal Dive International
    Global Industries
    Superior Offshore International
    Helix Energy Solutions
    McDermott International
    Acergy
    Subsea 7        
    Horizon Offshore 45




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##### Table of Contents




    Global Industries
    Superior Offshore International
    Helix Energy Solutions
    McDermott International
    Acergy
    Subsea 7        Comparable
    Transactions Analysis
    
    McDermott International / Secunda International Ltd.
    Helix Energy Solutions / Acergy
    SEACOR Holdings / Seabulk Holdings
    Oceaneering International / Subsea 7
    Helix Energy Solutions / Canyon Offshore
    Global Industries / Suez
    McDermott International / J. Ray McDermott   46




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##### Table of Contents



Discounted
    Cash Flow Analysis
      Premium
    Analysis
    
    Hercules Offshore / TODCO
    Tenaris / Hydril
    Universal / Hanover
    Superior Energy / Warrior Energy
    IPSCO / NS Group
    CGG / Veritas
    Tenaris / Maverick Tube
    SEACOR Holdings / Seabulk Holdings
    National Oilwell / Varco
    BJ Services / OSCA
    Technip / Coflexip
    Key Energy / Dawson Production 47




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##### Table of Contents




    Baker Hughes / Western Atlas
    EVI / Weatherford Enterra
    Halliburton / Dresser
    Camco / Production Operators
    Baker Hughes / Petrolite
    BJ Services / Nowsco Well Service  1-day, 5-days, 20-days
  Percentage Premium/(Discount) to the PricePrior to Transaction Announcement1-Day


5-Days


20-Days


52-Week HighSelected Transactions:Median


27.2
%


28.0
%


31.4
%


5.2
%Mean


28.1
%


29.6
%


31.8
%


1.8
%Max


83.6
%


58.4
%


81.1
%


31.7
%Min


2.4
%


5.6
%


(4.4
)%


(41.7
)%Implied Premium based on
    Horizons closing stock price as of June 8, 2007


13.8
%


11.9
%


22.6
%


(21.5
)%   Research
    Analyst Target Analysis
    Historical
    Common Stock Trading Analysis
  10-days, 20-days 30-days
  Contribution
    Analysis
   48




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##### Table of Contents



Pro
    Forma Merger Consequences Analysis
    Miscellaneous
       Cal
    Dives Reasons for the Merger    
    The combination of Cal Dives diving assets with
    Horizons derrick barges and complementary pipelay and pipe
    burial assets creates a company with a full spectrum of offshore
    construction services. 49




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##### Table of Contents




    The merger with Horizon provides Cal Dive with an immediate
    presence in attractive offshore regions outside the
    U.S. Gulf of Mexico and an enhanced ability to leverage the
    combined companys assets in new geographic regions.
    The merger achieves fleet expansion and diversity for
    Cal Dive more cost effectively and in a more timely fashion
    than could be achieved through new construction.
    The increased operating capabilities provide Cal Dive with
    the ability to generate significant new business opportunities
    and the potential for additional synergies through cost savings.
    The merger is expected to be accretive to Cal Dive for 2008
    earnings per share.
    The balanced cash and equity consideration provides
    Cal Dive with benefits to its projected earnings per share
    as well as maintaining conservative capitalization and majority
    ownership by Helix.
    The combined company after the merger is expected to generate
    significant free cash flow, allowing for debt reduction and the
    pursuit of strategic initiatives. Opinion
    of Banc of America Securities LLC  Financial Advisor
    to Cal Dive      The full text of Banc of America Securities written
    opinion to Cal Dives board of directors, which
    describes, among other things, the assumptions made, procedures
    followed, factors considered and limitations on the review
    undertaken, is attached as Annex C to this document and is
    incorporated by reference in its entirety into this document.
    Cal Dive shareholders are encouraged to read the opinion
    carefully in its entirety. The following summary of Banc of
    America Securities opinion is qualified in its entirety by
    reference to the full text of the opinion. Banc of America
    Securities delivered its opinion to Cal Dives board
    of directors for the benefit and use of Cal Dives
    board of directors in connection with and for purposes of its
    evaluation of the merger consideration to be paid by
    Cal Dive pursuant to the merger agreement. Banc of America
    Securities opinion does not address any other aspect of
    the merger and does not constitute a recommendation to any
    shareholder as to how to vote at the special meeting.
    
    reviewed certain publicly available business and financial
    information of Cal Dive and Horizon, respectively;
    reviewed certain internal financial statements and other
    financial, business and operating information and data
    concerning Cal Dive and Horizon, respectively;
    reviewed certain financial forecasts relating to Cal Dive
    prepared by the management of Cal Dive;
    reviewed certain financial forecasts relating to Horizon
    prepared by the management of Horizon and an alternative version
    of the Horizon forecasts incorporating adjustments thereto made
    by the management of Cal Dive; 50




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##### Table of Contents




    reviewed and discussed with senior executives of Cal Dive
    information relating to certain cost savings and strategic and
    operational benefits anticipated by the management of
    Cal Dive to result from the merger;
    discussed the past and current operations, financial condition
    and prospects of Horizon with senior executives of Cal Dive
    and Horizon, and discussed the past and current operations,
    financial condition and prospects of Cal Dive with senior
    executives of Cal Dive;
    reviewed the potential pro forma financial impact of the merger
    on the future financial performance of Cal Dive, including
    the potential effect on Cal Dives estimated earnings
    per share;
    reviewed the relative financial contributions of Cal Dive
    and Horizon to the future financial performance of the combined
    company on a pro forma basis following consummation of the
    merger;
    reviewed the reported prices and trading activity for
    Cal Dive common stock and Horizon common stock;
    compared the financial performance of Cal Dive and Horizon
    and the prices and trading activity of Cal Dive common
    stock and Horizon common stock with each other and with that of
    certain other publicly traded companies that Banc of America
    Securities deemed relevant;
    compared certain financial terms of the merger to financial
    terms, to the extent publicly available, of certain other
    acquisition transactions that Banc of America Securities deemed
    relevant;
    participated in discussions and negotiations among
    representatives of Cal Dive, Horizon and their respective
    advisors;
    reviewed the merger agreement; and
    performed such other analyses and considered such other factors
    as Banc of America Securities deemed appropriate.     51




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##### Table of Contents



The financial analyses summarized below include
    information presented in tabular format. In order to fully
    understand the financial analyses performed by Banc of America
    Securities, the tables must be read together with the text of
    each summary. The tables alone do not constitute a complete
    description of the financial analyses performed by Banc of
    America Securities. Considering the data in the tables below
    without considering the full narrative description of the
    financial analyses, including the methodologies and assumptions
    underlying the analyses, could create a misleading or incomplete
    view of the financial analyses performed by Banc of America
    Securities
  Horizon
    Financial Analyses
  Analysis of Selected Publicly Traded
    Companies.
  
    Acergy S.A.;
    Global Industries, Ltd.;
    McDermott International, Inc.;
    Oceaneering International, Inc.;
    Superior Offshore International, Inc.; and
    TETRA Technologies, Inc.    Implied Blended perShare Value ofImplied per Share Equity Reference Ranges for Horizon Based
    on:

Merger2007E EBITDA

2008E EBITDA

2007E EPS

2008E EPS

Consideration$16.50 - $22.25

$15.75 - $22.50

$14.00 - $22.50

$15.25 - $24.00

$
19.23    52




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##### Table of Contents



Analysis of Selected Precedent Transactions
  Announcement Date


Acquiror

Target3/19/07


Hercules Offshore, Inc.

TODCO2/20/06


SeaDrill Limited

Smedvig asa3/16/05


SEACOR Holdings Inc.

Seabulk International, Inc.5/15/02


ENSCO International Incorporated

Chiles Offshore Inc.5/8/02


Saipem SPA

Bouygues Construction  SA9/4/01


Santa Fe International Inc

Global Marine Inc.7/3/01


Technip

Coflexip Stena Offshore Group S.A.5/24/01


Pride International, Inc.

Marine Drilling Companies, Inc.8/21/00


Transocean Sedco Forex Inc

R&B Falcon Corporation7/12/99


Transocean Offshore Inc

Sedco Forex, Inc.8/10/98


R&B Falcon Corporation

Cliffs Drilling Company7/10/97


Falcon Drilling Company, Inc.

Reading & Bates Corporation     Implied per Share Equity ReferenceRange for Horizon Based on LTM

Implied Blended per Share Value ofEBITDA

Merger Consideration$19.00 - $26.25

$
19.23     Discounted Cash Flow Analysis.
 53




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##### Table of Contents



Implied per Share Equity Reference

Implied Blended per Share Value ofRange for Horizon

Merger Consideration$18.25 - $23.75

$
19.23   Premiums Paid Analysis.
  All
    Transactions
  Implied per ShareValue of HorizonPremium


Common StockPeriod Prior to Announcement

Horizon Share Price


Mean


Median


Mean


MedianOne Day

$
16.90



22.8
%


18.8
%

$
20.75


$
20.08One Week

$
16.94



23.5
%


24.6
%

$
20.92


$
21.11Four Weeks

$
15.69



30.4
%


29.0
%

$
20.45


$
20.23   Cash Only
    Transactions
  Implied per ShareValue of HorizonPremium


Common StockPeriod Prior to Announcement

Horizon Share Price


Mean


Median


Mean


MedianOne Day

$
16.90



24.7
%


26.7
%

$
21.07


$
21.41One Week

$
16.94



26.7
%


28.2
%

$
21.46


$
21.71Four Weeks

$
15.69



31.6
%


38.9
%

$
20.66


$
21.79     Cal
    Dive Financial Analyses
  Analysis of Selected Publicly Traded
    Companies.
  
    Acergy S.A.;
    Global Industries, Ltd.;
    McDermott International, Inc.;
    Oceaneering International, Inc.; 54




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##### Table of Contents




    Superior Offshore International, Inc.; and
    TETRA Technologies, Inc.    Implied per Share Equity Reference Range for Cal Dive Based
    on:2007E EBITDA

2008E EBITDA

2007E EPS

2008E EPS$15.75 - $21.50

$14.00-$20.50

$15.00-$24.25

$15.00-$23.50     Discounted Cash Flow Analysis.
  Implied per Share Equity Reference

Closing Price of Cal Dive CommonRange for Horizon

Stock on June 8, 2007$14.75 - $20.25

$
15.96   Pro
    Forma Merger Accretion/Dilution Analysis
    Other
    Factors
    
    historical trading prices and trading volumes of
    (i) Horizons shares since June 2006, when Horizon
    completed its financial reorganization and resumed trading on
    Nasdaq, and (ii) Cal Dives shares since
    Cal Dives initial public offering on
    December 14, 2006; 55




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##### Table of Contents




    the historical ratio of Horizons closing share price to
    Cal Dives closing share price since
    Cal Dives initial public offering on
    December 14, 2006;
    the relative value of Horizon shares and Cal Dive shares
    using the reference ranges of implied values obtained under the
    selected publicly traded companies, selected precedent
    transactions and discounted cash flow analyses described above;
    the relative contributions of Horizon and Cal Dive to the
    EBITDA, net income, cash flow, equity value and firm value of
    the combined company; and
    publicly available research analysts reports for Horizon
    and Cal Dive, including revenue, EBITDA, EPS and cash flow
    per share estimates reflected in those reports.  Miscellaneous
         56




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##### Table of Contents



and/or
 Accounting
    Treatment   Opinions
    that the Merger Constitutes a Reorganization under
    Section 368(a) of the Internal Revenue Code   Regulatory
    Matters  Hart-Scott-Rodino
     Appraisal
    Rights   57




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##### Table of Contents



THE FOLLOWING DISCUSSION IS NOT A COMPLETE STATEMENT OF THE
    LAW PERTAINING TO APPRAISAL RIGHTS UNDER THE DGCL AND IS
    QUALIFIED IN ITS ENTIRETY BY THE FULL TEXT OF SECTION 262
    OF THE DGCL, WHICH IS REPRINTED IN ITS ENTIRETY AS ANNEX D.
    ALL REFERENCES IN SECTION 262 OF THE DGCL AND IN THIS
    SUMMARY TO A STOCKHOLDER OR HOLDER ARE
    TO THE RECORD HOLDER OF THE SHARES OF COMMON STOCK AS TO WHICH
    APPRAISAL RIGHTS ARE ASSERTED.
           58




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##### Table of Contents



ALL WRITTEN DEMANDS FOR APPRAISAL SHOULD BE SENT OR DELIVERED
    TO HORIZON OFFSHORE, INC., 2500 CITYWEST BOULEVARD,
    SUITE 2200, HOUSTON, TEXAS 77042, ATTENTION: SECRETARY.
             59




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##### Table of Contents



Delisting
    and Deregistration of Horizon Common Stock   Federal
    Securities Laws Consequences; Resale Restrictions     INTERESTS
    OF HORIZON DIRECTORS AND EXECUTIVE OFFICERS IN THE
    MERGER   60




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##### Table of Contents



Stock
    Options and Restricted Stock        Value of





Value ofStock


Stock


Common


CommonName and Principal Position

Options


Options


Stock


StockDavid. W. Sharp,










88,179


$
1,623,375President, Chief Executive Officer
    and DirectorRonald D. Mogel,










9,122



167,936Vice President, Chief Financial
    Officer and TreasurerGeorge G. Reuter,










73,736



1,357,480Executive Vice President and Chief
    Operating OfficerWilliam B. Gibbens, III,










73,183



1,347,299Executive Vice President, General
    Counsel and SecretaryJohn T. Mills,


10,800







4,529



83,379Chairman of the BoardCharles O. Buckner,


10,800







4,529



83,379DirectorKen R. LeSuer,


11,000







4,529



83,379DirectorRaymond L. Steele,


10,400







4,529



83,379Director  Change in
    Control Severance Agreements   61




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##### Table of Contents



Positions
    of Certain Horizon Directors After the Merger   Indemnification
    of Horizon Officers and Directors   D&O
    Insurance   Ownership
    of Horizon Common Stock   Retention
    Bonus Plan for Salaried Personnel   62




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##### Table of Contents



MATERIAL
    U.S. FEDERAL INCOME TAX CONSEQUENCES General    
    an individual who is a citizen or resident of the United States
    (including certain former citizens and former long-term
    residents);
    a corporation, or other entity taxable as a corporation for
    U.S. federal tax purposes, created or organized in or under
    the laws of the United States or any state thereof or the
    District of Columbia;
    an estate the income of which is subject to U.S. federal
    income taxation regardless of its source; or
    a trust (i) that is subject to the primary supervision of a
    court within the United States and the control of one or more
    United States persons as defined in section 7701(a)(30) of
    the Code or (ii) that has a valid election in effect under
    applicable Treasury regulations to be treated as a United States
    person.    statement/prospectus
        THIS SUMMARY IS NOT A SUBSTITUTE FOR AN INDIVIDUAL ANALYSIS
    OF THE TAX CONSEQUENCES OF THE MERGER TO YOU. WE URGE YOU TO
    CONSULT YOUR TAX ADVISOR REGARDING THE PARTICULAR FEDERAL,
    STATE, LOCAL, AND FOREIGN TAX CONSEQUENCES OF THE MERGER AND THE
    OWNERSHIP AND DISPOSITION OF SHARES
 63




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##### Table of Contents



OF CAL DIVE COMMON STOCK RECEIVED IN THE MERGER IN LIGHT OF
    YOUR OWN SITUATION.
     Tax
    Consequences of the Merger to Horizon Stockholders  The
    Merger
    
    the amount of cash received pursuant to the merger (excluding
    any cash received in lieu of fractional shares of Cal Dive
    common stock), and
    the amount, if any, by which the sum of the fair market value of
    the shares of Cal Dive common stock as of the effective
    time of the merger and the amount of cash received pursuant to
    the merger for those Horizon shares exceeds his adjusted tax
    basis in those Horizon shares.       64




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##### Table of Contents




    reduced by the amount of cash received in the merger by him for
    those Horizon shares (excluding any cash received in lieu of a
    factional share of Cal Dive common stock); and
    increased by the amount of gain (including the portion of this
    gain that is treated as a dividend as described above)
    recognized by him in the merger (excluding any gain recognized
    as a result of any cash received in lieu of a fractional share
    of Cal Dive common stock).         65




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##### Table of Contents



Information
    Reporting and Backup Withholding
  Form W-9 Form W-9
    The foregoing discussion is for general information only and
    not intended to be legal or tax advice to any particular Horizon
    stockholder. Tax matters regarding the merger are very
    complicated, and the tax consequences of the merger to any
    particular Horizon stockholder will depend on that
    stockholders particular situation. Horizon stockholders
    should consult their own tax advisor to determine the specific
    tax consequences of the merger, including tax return reporting
    requirements, the applicability of U.S. federal, state,
    local, and foreign tax laws and the effect of any proposed
    change in the tax laws to them.
 THE
    MERGER AGREEMENT     66




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##### Table of Contents



Structure
    of the Merger   Timing of
    Closing     Merger
    Consideration   Fractional
    Shares   Potential
    Adjustment to Merger Consideration   Treatment
    of Horizon Stock Options and Restricted Stock   67




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##### Table of Contents



Conversion
    of Shares     Exchange
    Procedures        HORIZON STOCK CERTIFICATES SHOULD NOT BE RETURNED WITH THE
    ENCLOSED PROXY CARD. HORIZON STOCK CERTIFICATES SHOULD BE
    RETURNED WITH THE TRANSMITTAL LETTER AND ACCOMPANYING
    INSTRUCTIONS WHICH WILL BE PROVIDED TO HORIZON STOCKHOLDERS
    FOLLOWING THE EFFECTIVE TIME OF THE MERGER.
 68




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##### Table of Contents



Managers
    and Officers of the Surviving Company After the Merger   Representations
    and Warranties    
    corporate organization, qualification, good standing and
    organizational power;
    ownership of equity interests;
    corporate power and authority to enter into the merger
    agreement, and due execution, delivery and enforceability of the
    merger agreement;
    absence of a breach of charter documents or bylaws as a result
    of the merger;
    absence of breaches of material agreements, instruments or
    obligations, or violations of applicable law as a result of the
    merger reasonably expected to have a material adverse effect;
    consents, approvals, orders, authorizations, registrations,
    declarations, filings and permits required to enter into the
    merger agreement or to complete the transactions contemplated by
    the merger agreement;
    timely and accurate filings with the Securities and Exchange
    Commission in compliance with applicable rules and regulations;
    financial statements;
    capital structure;
    absence of undisclosed liabilities;
    absence of specified adverse changes or events since
    March 31, 2007;
    material contracts;
    compliance with laws, material agreements and permits;
    governmental regulation;
    material litigation, material judgments or injunctions and
    absence of undisclosed investigations or litigation;
    absence of certain restrictive agreements or arrangements;
    tax matters;
    employee benefit plans and labor matters;
    insurance matters;
    title to assets;
    environmental matters;
    books and records;
    brokers and finders fees;
    disclosure controls and procedures and internal control over
    financial reporting;
    required vote/approval by Cal Dive stockholders;
    recommendation of Horizon board of directors and opinion of
    financial advisor; 69




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##### Table of Contents




    vessels; and
    inapplicability of Delaware anti-takeover statute.   Covenants
    and Agreements   Operating
    Covenants  Horizon    
    enter into any new material line of business or incur or commit
    to any capital expenditures or any obligations or liabilities in
    connection therewith other than capital expenditures and
    obligations or liabilities in connection therewith incurred or
    committed to in the ordinary course of business consistent with
    past practice or contemplated by the 2007 capital budget of
    Horizon and previously disclosed to Cal Dive;
    split, combine or reclassify any of its outstanding capital
    stock;
    declare, set aside or pay any dividends or other distributions
    with respect to its capital stock (other than regular dividends
    from a Horizon subsidiary to Horizon or to another subsidiary
    consistent with past practice);
    issue, sell or agree to issue or sell any securities or other
    equity interests, including its capital stock, any rights,
    options or warrants to acquire its capital stock, or securities
    (other than shares of Horizon common stock issued pursuant to
    the exercise of its stock options or restricted stock awards
    outstanding on the date of the merger agreement or permitted to
    be granted in accordance with their terms and shares of capital
    stock of Horizons subsidiaries under certain permitted
    circumstances);
    amend or propose to amend Horizons amended and restated
    certificate of incorporation or bylaws (except as may be
    required to comply with the terms of the merger agreement or
    applicable law);
    purchase, cancel, retire, redeem or otherwise acquire any of its
    outstanding capital stock or other securities or other equity
    interests, except pursuant to the terms of the Horizon benefit
    plans;
    acquire any corporation, partnership or other business entity or
    any interest therein (other than acquisitions made or in the
    ordinary course of business that could not reasonably be
    expected to prevent or materially delay the or impede the merger
    transactions);
    sell, lease, transfer or otherwise dispose of any of its assets
    other than in the ordinary course or as previously disclosed;
    make any loans, advances or capital contributions to, or
    investments in any other person (other than loans or investments
    by Horizon or one of its subsidiaries to or in Horizon or
    another subsidiary, or certain other loans made in the ordinary
    course of business consistent with past practice or previously
    disclosed); or
    incur any indebtedness other than in the ordinary course of
    business consistent with past practice, to refinance
    pre-existing indebtedness or to fund acquisitions that are
    otherwise permitted under the merger agreement. 70




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##### Table of Contents




    carry on their respective businesses in the usual, regular, and
    ordinary course in all material respects, in substantially the
    same manner as previously conducted, and in compliance in all
    material respects with applicable laws;
    use their reasonable best efforts to keep available the services
    of their respective present officers and key employees, preserve
    intact their present lines of business, maintain their rights
    and franchises, and preserve their relationships with customers,
    suppliers, and others having business dealings with them to the
    end that their ongoing businesses shall not be impaired in any
    material respect at the effective time of the merger; and
    use their reasonable best efforts to cause the merger to qualify
    as a reorganization within the meaning of the Code. Operating
    Covenants  Cal Dive    
    split, combine or reclassify any of its outstanding capital
    stock;
    declare, set aside or pay any dividends or other distributions
    with respect to its capital stock (other than regular dividends
    from a Cal Dive subsidiary to Cal Dive or to another
    subsidiary consistent with past practice);
    issue, sell or agree to issue or sell any securities or other
    equity interests, including its capital stock, any rights,
    options or warrants to acquire its capital stock, or securities
    (other than shares of Cal Dive common stock issued pursuant
    to the exercise of its stock options or restricted stock awards
    outstanding on the date of the merger agreement or permitted to
    be granted in accordance with their terms);
    amend or propose to amend Cal Dives amended and
    restated certificate of incorporation or bylaws (except as may
    be required to comply with the terms of the merger agreement or
    applicable law);
    purchase, cancel, retire, redeem or otherwise acquire any of its
    outstanding capital stock or other securities or other equity
    interests, except pursuant to the terms of the Cal Dive
    benefit plans or pursuant to a stock repurchase plan implemented
    in the ordinary course;
    acquire any corporation, partnership or other business entity or
    any interest therein (other than acquisitions made in the
    ordinary course of business that could not reasonably be
    expected to prevent or materially delay the or impede the merger
    transactions);
    sell, lease, transfer or otherwise dispose of any of its assets
    other than in the ordinary course or as previously disclosed;
    make any loans, advances or capital contributions to, or
    investments in any other person (other than loans or investments
    by Cal Dive or one of its subsidiaries to or in
    Cal Dive or another subsidiary, or certain other loans made
    in the ordinary course of business consistent with past practice
    or previously disclosed by Cal Dive); or
    incur any indebtedness other than in the ordinary course of
    business consistent with past practice, to refinance
    pre-existing indebtedness or to fund acquisitions that are
    otherwise permitted under the merger agreement. 71




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##### Table of Contents




    carry on their respective businesses in the usual, regular, and
    ordinary course in all material respects, in substantially the
    same manner as previously conducted, and in compliance in all
    material respects with applicable laws;
    use their reasonable best efforts to preserve intact their
    present lines of business, maintain their rights and franchises,
    and preserve their relationships with customers, suppliers, and
    others having business dealings with them to the end that their
    ongoing businesses shall not be impaired in any material respect
    at the effective time of the merger; and
    use their reasonable best efforts to cause the merger to qualify
    as a reorganization within the meaning of the Code. No
    Control of Other Partys Business   Non-Solicitation
    Provisions and Acquisition Proposals    
    a merger, reorganization, share exchange, consolidation,
    business combination, recapitalization, liquidation,
    dissolution, or similar transaction involving Horizon, or
    any purchase or sale of 50% or more of the consolidated assets
    (including stock of Horizons subsidiaries) of Horizon and
    its subsidiaries, taken as a whole, or
    any purchase or sale of, or tender or exchange offer for,
    Horizons equity securities that, if consummated, would
    result in any person (or the stockholders of such person)
    beneficially owning securities representing 50% or more of
    Horizons total voting power (or of the surviving parent
    entity in such transaction) (other than a proposal or offer made
    by a party to the merger agreement or an affiliate
    thereof), or
    an announcement of an intention to make any such proposal,
    offer, or transaction.    
    initiate, solicit, encourage or seek, directly or indirectly,
    any inquiries relating to the making or implementation of and
    Acquisition Proposals;
    continue or otherwise engage or participate in any negotiations
    or discussions with any third party with respect to Acquisition
    Proposals, including by providing third parties with non-public
    information pursuant to an acceptable confidentiality agreement
    (provided that the same information is also provided or
    otherwise made available to Cal Dive either before or
    substantially at the same time it is given to the third party,
    subject to limited exceptions set forth in the merger
    agreement); and
    release any third party from, or waive any provision of, any
    confidentiality or standstill agreement to which Horizon is a
    party to the extent necessary to allow Horizon to conduct such
    solicitation, negotiations or discussions.   72




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
    initiate, solicit, knowingly encourage, or seek, directly or
    indirectly, any inquiries relating to or the making or
    implementation of any Acquisition Proposal;
    engage in any negotiations or substantive discussions with any
    third party relating to an Acquisition Proposal (except for
    discussions solely in order to clarify and understand the terms
    and conditions of a written Acquisition Proposal, which are
    allowed prior to Horizons stockholders approving the
    merger agreement with Cal Dive);
    provide or otherwise make available any information to any third
    party relating to an Acquisition Proposal;
    enter into any letter of intent, agreement in principle, merger
    agreement, acquisition agreement, option agreement, or similar
    agreement with any person relating to an Acquisition
    Proposal; or
    release any third party from, or waive any provision of, any
    confidentiality or standstill agreement to which it is a party
    relating to an Acquisition Proposal;      
    withdraw, modify, or qualify (or propose to withdraw, modify, or
    qualify) in any manner adverse to Cal Dive, its
    recommendation that the merger agreement be approved by
    Horizons stockholders;
    take any action or make any statement in connection with the
    meeting of Horizons stockholders held for the purpose of
    adopting the merger agreement that is inconsistent with its
    recommendation that the merger agreement be approved by
    Horizons stockholders;
    approve or recommend, or cause Horizon to enter into, any letter
    of intent, agreement in principle, merger agreement, acquisition
    agreement, option agreement, or similar agreement with respect
    to, any Acquisition Proposal; or
    propose to do any of the foregoing;    
    modify, change, or contradict its recommendation that the merger
    agreement be approved; and/or
    enter into a definitive agreement providing for an Acquisition
    Proposal if (i) Horizon, its subsidiaries, and their
    representatives have not materially violated the rules described
    above, (ii) such action is in response to a Acquisition
    Proposal that the board has determined, in its good faith
    judgment, constitutes 73




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a Superior Proposal, and (iii) Horizon, concurrently with
    the entering into of such definitive agreement, terminates the
    merger agreement pursuant to its terms, and pays the appropriate
    termination fee as specified therein;      Rules 14d-9 14e-2(a)
 Employee
    Benefit Matters       74




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Directors
    and Officers Indemnification and Insurance       Affiliate
    Agreements    
    in compliance with Rule 145 under the Securities Act of
    1933;
    pursuant to an effective registration statement under the
    Securities Act of 1933; or
    in reliance upon an opinion of counsel reasonably acceptable to
    Cal Dive, to the effect that the sale, transfer or other
    disposition is exempt from registration under the Securities Act
    of 1933. Tax
    Matters   Additional
    Agreements    
    convening and holding the Horizon special meeting; 75




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
    preparing, filing and distributing this information
    statement/proxy statement/prospectus and filing the registration
    statement of which this information statement/proxy
    statement/prospectus is a part;
    providing access to information to each other;
    using their reasonable best efforts regarding filings with and
    obtaining waivers, consents and approvals from governmental and
    other agencies and organizations, including HSR filings;
    making public announcements;
    payment of fees and expenses in connection with the merger;
    tax matters;
    vessel matters;
    matters related to Section 16 of the Exchange Act;
    appointing David W. Sharp and John T. Mills as additional
    members of the Cal Dive board of directors for initial
    terms expiring at the annual meeting of Cal Dives
    stockholders to be held in 2010; and
    listing of the shares of Cal Dive common stock to be issued
    in connection with the merger on the New York Stock
    Exchange, subject to official notice of issuance. Conditions
    Precedent Conditions
    to Each Partys Obligation to Effect the
    Merger    
    absence of any temporary restraining order, preliminary or
    permanent injunction or other order issued by a court of
    competent jurisdiction or other law, legal restraint or
    prohibition having the effect of making the merger illegal or
    otherwise prohibiting the consummation of the merger; and
    receipt of approvals and authorizations required under the
    antitrust laws, including expiration or early termination of the
    waiting period under the
    Hart-Scott-Rodino
    Act, to consummate the transactions contemplated by the merger
    agreement;
    approval for listing of the Cal Dive shares to be issued in
    the merger on the New York Stock Exchange, subject to official
    notice of issuance.
    continued effectiveness of the registration statement of which
    this information statement/proxy statement/prospectus is a part,
    the absence of a stop order by the Securities and Exchange
    Commission suspending the effectiveness of the registration
    statement and the absence of any continuing or threatened
    proceeding or investigation by the Securities and Exchange
    Commission to suspend such effectiveness; and
    adoption of the merger agreement by the holders of at least a
    majority of the outstanding Horizon shares entitled to vote at
    the Horizon special meeting. Conditions
    to Obligations of Cal Dive    
    accuracy of the representations and warranties made by Horizon
    to the extent specified in the merger agreement;
    Horizons performance in all material respects of its
    covenants and agreements under the merger agreement; and 76




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
    receipt of an opinion satisfactory to Cal Dive of its tax
    counsel to the effect that the merger will constitute a
    reorganization within the meaning of Section 368(a) of the
    Code. Conditions
    to Obligations of Horizon    
    accuracy of the representations and warranties made by
    Cal Dive to the extent specified in the merger agreement;
    Cal Dives performance in all material respects of
    their covenants and agreements under the merger
    agreement; and
    receipt of an opinion satisfactory to Horizon of its tax counsel
    to the effect that the merger will constitute a reorganization
    within the meaning of Section 368(a) of the Code. Termination    
    by mutual written consent of Cal Dive and Horizon;
    by either Cal Dive or Horizon, if:  
    the parties fail to consummate the merger on or before
    December 11, 2007, unless the failure is the result of a
    failure to fulfill an obligation under the merger agreement by
    the party seeking the termination;
    any governmental authority has issued a final and nonappealable
    order, decree or ruling or has taken any other final and
    nonappealable action that restrains, enjoins or prohibits the
    merger, or has failed to issue an order, decree, ruling, or
    failed to take any action that is necessary to obtain approval
    under the HSR Act, to list the shares to be issued in the merger
    on the NYSE, or obtain and maintain effectiveness of the
    registration statement, unless the party seeking the termination
    has not used all reasonable efforts to remove such injunction,
    order or decree, or to obtain such approvals; or
    adoption of the merger agreement by the Horizon stockholders is
    not obtained by reason of the failure to obtain the required
    vote of Horizons stockholders.  
    by Cal Dive, if:  
    Horizons board of directors (1) fails to recommend
    the approval or recommendation of the merger agreement or
    (2) makes a change in its recommendation that
    Horizons stockholders approve the merger agreement;
    Horizon breaches its obligations under the merger agreement by
    reason of a failure to call the Horizon stockholders meeting or
    a failure to comply in any material respect with requirements
    set forth in the merger agreement regarding the preparation of
    this information statement/proxy statement/prospectus;
    Horizon enters into a definitive agreement providing for an
    Acquisition Proposal or Superior Proposal (unless Horizon does
    so in accordance with its fiduciary out as provided under the
    terms of the merger agreement);
    Horizon breaches in any material respect its covenant not to
    solicit, initiate or knowingly encourage any inquiries, offers
    or proposals that constitute, or are reasonably likely to lead
    to, an alternate acquisition proposal or engaged in certain
    prohibited activities with respect thereto; or
    Horizon breaches any of its representations or warranties set
    forth in the merger agreement or Horizon fails to perform its
    covenants or agreements under the merger agreement and, in
    either 77




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case, Horizon has not cured the breach or failure within the
    earlier of (x) 20 days of receiving notice from
    Cal Dive of such breach or failure or
    (y) December 11, 2007, provided that Cal Dive is
    not then in material beach of any of its covenants,
    representations of warranties under the merger agreement.  
    by Horizon, if:  
    prior to approval by Horizons stockholders of the merger
    agreement, the Horizon board of directors approves a Superior
    Proposal in accordance with the terms set forth in the merger
    agreement; or
    Cal Dive breaches any of its representations or warranties
    set forth in the merger agreement or Cal Dive fails to
    perform its covenants or agreements under the merger agreement
    and, in either case, Cal Dive has not cured the breach or
    failure within the earlier of (x) 20 days of receiving
    notice from Horizon of such breach or failure or
    (y) December 11, 2007, provided that Horizon is not
    then in material beach of any of its covenants, representations
    of warranties under the merger agreement.   Fees and
    Expenses     Amendment   Extension;
    Waiver    
    extend the time for the performance of any of the obligations or
    the other acts of the other parties;
    waive any inaccuracies in the representations and warranties
    contained in the merger agreement or in any document delivered
    pursuant to the merger agreement; or
    waive performance of any of the covenants or agreements, or
    satisfaction of any of the conditions, contained in the merger
    agreement. 78




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INFORMATION
    ABOUT CAL DIVE Business  General
        step-up
 79




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Certain
    Definitions
    
    Dive support vessel (DSV):  Specially equipped
    vessel that performs services and acts as an operational base
    for divers, ROVs and specialized equipment.
    Drydock:  The process of docking a vessel so
    that it is fully supported out of the water for the purposes of
    regulatory certification, inspection, maintenance and repair.
    Drydocking allows full work access to the vessel hull.
    Dynamic positioning (DP):  Computer-directed
    thruster systems that use satellite-based positioning and other
    positioning technologies to ensure the proper counteraction to
    wind, current and wave forces, enabling the vessel to maintain
    its position without the use of anchors. Two DP systems (DP-2)
    are necessary to provide the redundancy required to support safe
    deployment of divers, while only a single DP system is necessary
    to support ROV operations.
    EIA:  United States Department of Energy,
    Energy Information Administration.
    4 point mooring:  A mooring system that uses
    four anchors, which are spooled out to the sea floor by
    deck-mounted anchor winches, to secure a vessel in open waters.
    Gulf of Mexico OCS:  The Outer Continental
    Shelf in the Gulf of Mexico, defined as the area in the Gulf of
    Mexico extending from the shoreline to water depths up to
    1,000 feet.
    Hyperbaric rescue chamber (HRC):  An additional
    chamber, connected to the saturation diving system, that acts as
    a floating pressurized lifeboat in the event of a vessel
    emergency.
    Mixed gas diving:  Diving technique used in
    water depths between 170 and 300 feet. The inert nitrogen
    normally found in air is replaced with helium, which provides
    longer bottom times at greater depths and eliminates the
    narcotic effect of nitrogen under pressure.
    MMS:  United States Department of Interior,
    Minerals Management Service.
    Moon pool:  An opening in the bottom center of
    a vessel through which a saturation diving system or ROV may be
    deployed, allowing safer deployment in adverse weather
    conditions.
    Multi-purpose support vessel (MSV):  A DP DSV
    that is capable of performing coring and well operations in
    addition to working in diving and ROV modes.
    Pipelay and pipe burial:  Pipelay barges
    provide an offshore work station that allow for the welded
    assembly of multiple sections of pipe on deck. After completing
    nondestructive testing, the barge pulls forward on the anchor
    spread moorings and lays out the pipeline on the seafloor. In
    water depths less than 200 feet, the pipeline is required
    to have a minimum of three feet of burial cover. Burial is
    accomplished by digging and jetting out a trenched ditch from
    under the pipeline.
    Portable saturation diving system:  Saturation
    diving system that is transportable to various offshore
    locations. These systems are typically deployed on barges and
    rigs that do not consistently require deep dive support.
    Qualified turnkey:  Lump-sum bid sent in
    response to a clients request for quote. Our bid response
    contains the following: a defined scope of work, a lump-sum
    price to complete that work, extra work rates for anything
    outside the defined scope of work and a list of clarifications
    and qualifications applicable to the project or contract.
    Remotely operated vehicle (ROV):  Robotic
    vehicles used to complement, support and increase the efficiency
    of diving and subsea operations and for tasks beyond the
    capability of manned diving operations. 80




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
    Saturation diving:  Provides for efficient work
    time on the seafloor in water depths between 200 and
    1,000 feet. Divers stay under pressure in a vessel-mounted
    chamber and are transported to the sea floor in a diving bell.
    One-time decompression is conducted after completion of the job
    or a 30-day
    period, whichever is shorter. A split-level saturation diving
    system has an additional chamber that allow extra divers to
    store at a different pressure level, which allows
    the divers to work at different depths.
    Surface diving:  Diving operations conducted in
    shallower waters, typically limited to depths of approximately
    170 feet. At greater depths, bottom times become limited
    and decompression times increase significantly. Compressed air
    and communications are supplied to the diver through a dive
    umbilical tethered to the surface. Based on factors of depth and
    time, divers must decompress after each dive.
    Surface diving system:  Dive equipment
    components required for air or gas surface diving operations,
    which typically includes air compressors, dive hoses,
    communication radios, air/gas manifolds and decompression
    chambers.  Recent
    Acquisitions and Investments
    
    In August 2005, we acquired six vessels and a portable
    saturation diving system from Torch Offshore, Inc., or Torch,
    for an aggregate purchase price of $26.2 million (including
    assets held for sale).
    In late 2005 and early 2006, we acquired all of the diving and
    shallow water pipelay business of Acergy US, Inc. (formerly
    known as Stolt Offshore Inc.), or Acergy, operating in the Gulf
    of Mexico and Trinidad, including nine vessels and one portable
    saturation diving system, for an aggregate purchase price of
    $124.3 million.      Geographic
    Areas
    Year Ended December 31,


Six Months Ended June 30,2006


2005


2004


2007


2006$


%


$


%


$


%


$


%


$


%United States

$
439,474



86.2
%

$
190,739



85.0
%

$
106,232



84.5
%

$
218,237



76.7
%

$
213,773



87.4
%International


70,443



13.8
%


33,560



15.0
%


19,554



15.5
%


66,247



23.3
%


30,781



12.6
%$
509,917



100
%

$
224,299



100
%

$
125,786



100
%

$
284,484



100
%

$
244,554



100
%     Year Ended December 31,


Six Months Ended June 30,2006


2005


2004


2007


2006$


%


$


%


$


%


$


%


$


%United States

$
173,173



77.9
%

$
91,094



80.2
%

$
52,671



69.0
%

$
168,614



74.6
%

$
141,739



77.2
%International


49,074



22.1
%


22,510



19.8
%


23,658



31.0
%


57,421



25.4
%


41,973



22.8
%$
222,247



100
%

$
113,604



100
%

$
76,329



100
%

$
226,035



100
%

$
183,712



100
%  81




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##### Table of Contents



Marine
    Contracting Industry
    Increased capital spending by oil and natural gas
    producers.
  Rising international offshore activity.
  Aging production infrastructure in the Gulf of
    Mexico.
  Growing U.S. demand for natural gas.
 82




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Competitive
    Strengths
    
    Leader in the Gulf of Mexico OCS diving services
    market.  We believe the size of our fleet and
    workforce makes us the market leader for diving services on the
    Gulf of Mexico OCS. We currently own and operate a diversified
    fleet of 26 vessels and employ approximately 1,300 diving
    and marine personnel. We believe our size advantage allows us to
    provide the highest quality diving services on the Gulf of
    Mexico OCS and contributes to our leading share of diving
    services contracts in this market. Furthermore, we expect to
    achieve similar leadership in new offshore markets due to our
    superior operating capabilities, international experience,
    existing relationships with globally focused customers and
    proven acquisition expertise.
    High-quality asset base.  Our diverse fleet of
    vessels and diving systems, particularly our saturation diving
    fleet, is among the most technically advanced in the industry.
    Our saturation diving fleet has a combination of modern
    features, including DP, multi-chamber systems for split-level
    operations and moon pool deployment, that allow us to operate
    effectively in challenging offshore environments. The diversity
    of our fleet also enables us to provide a wide range of marine
    contracting services. We possess complementary diving, pipelay
    and pipe burial capabilities that are often required for more
    complex subsea projects. As a result, we can effectively execute
    this higher margin business while enhancing the utilization of
    our diving support vessels.
    Highly skilled workforce.  The quality of our
    workforce has been, and will continue to be, a vital contributor
    to our success. We invest significant resources in training
    programs to ensure that our divers, supervisors and support
    staff have the best technical, operational and safety skills in
    the industry, which allows us to deliver innovative solutions to
    our customers. In addition, our market leadership provides an
    advantage with regard to employee retention, which is a major
    issue in our sector in the current tight labor environment. The
    compensation of our divers is typically determined by their
    logged diving time, so divers and others are strongly
    incentivized to work for us due to our high vessel utilization,
    which is driven by our relationships with the most active Gulf
    of Mexico producers and proven operating history. We believe
    these qualities, along with our commitment to effective training
    and safety, help us to attract and retain skilled employees.
    Excellent, long-standing customer
    relationships.  We have built a reputation as a
    premier diving services contractor during our more than
    30 years operating in the Gulf of Mexico. We have developed
    a large and stable customer base, which includes virtually all
    of the top 20 energy producers in the Gulf of Mexico, by
    consistently providing superior and comprehensive services on
    schedule while maintaining a strong safety track record.
    Successful acquisition track record.  We have a
    proven track record of identifying and executing acquisitions
    that complement our fleet and workforce and enhance our service
    capabilities. In 2005, we added 13 vessels, including three
    premium saturation diving vessels, and two portable saturation
    diving systems to our fleet. More recently, in July 2006, we
    completed the acquisition of six portable saturation diving
    systems and 15 surface diving systems operating primarily in the
    Middle East, Southeast Asia and Australia from Singapore-based
    Fraser Diving. We attribute much of the growth of our business
    to our success making acquisitions, and we believe that
    acquisitions will remain a key element of our growth strategy.
    Furthermore, we believe that our ability to integrate
    acquisitions efficiently is one of our core organizational
    competencies. We have consistently demonstrated the ability to
    add to our revenue base and retain key personnel from acquired
    businesses, while improving margins by leveraging our existing
    cost structure.
    Proven management team with extensive experience in the
    marine contracting business.Most of our executive officers
    and senior managers have spent the majority of their respective
    careers in the marine 83




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contracting business, working at various levels of the industry
    in the Gulf of Mexico and internationally. This senior
    management team, which has an average of 22 years of
    industry experience, includes recognized leaders in diving
    services and offshore construction. Several of these individuals
    serve in high-ranking positions in industry organizations for
    standards and safety. We believe the knowledge and experience of
    our management team provides a valuable competitive advantage.  Business
    Strategy
    
    Strengthen leadership position on the Gulf of Mexico
    OCS.  We will seek to expand our leadership
    position in the Gulf of Mexico OCS diving services market by
    enhancing the capabilities of our existing assets, making
    acquisitions of complementary assets or businesses and
    continuing to provide a high level of customer service. Pursuant
    to this strategy, we have increased the crane capacity of the DP
    DSV Kestrel and plan to convert the DSV Midnight Star surface
    diving vessel to a saturation diving vessel in 2008. We believe
    these upgrades will increase the demand for those assets, and we
    intend to invest future available capital in similar fleet
    enhancements. As evidence of our continued success in this
    market, in 2006 we entered into a new diving services contract
    with a major oil company, the largest such contract in our
    history based on potential revenues of approximately
    $80 million for work that we expect to continue through
    February 2008.
    Expand into high-growth international markets through
    acquisitions.  Several international regions, such
    as the Middle East, Southeast Asia and Australia, offer
    excellent growth potential attributable to the recent and
    planned increases in upstream capital spending and the highly
    fragmented nature of the existing marine contracting markets. We
    are continually evaluating potential acquisition targets that
    can provide us with a more meaningful presence in these markets.
    Our goal is to replicate our Gulf of Mexico OCS leadership in
    the most attractive international offshore regions by leveraging
    our operating capabilities, international experience, customer
    relationships and acquisition expertise. Pursuant to this
    strategy, in July 2006, we completed an acquisition of the
    business of Singapore-based Fraser Diving.
    Continue to attract, develop and retain highly skilled
    personnel.  Our market leadership and future
    growth plans are predicated on our ability to employ the most
    highly-skilled divers, supervisors and support staff in the
    industry. We invest significant resources in developing the
    technical, operational and safety skills of our workforce. We
    will continue to invest significant resources in training and
    development courses that will provide our workforce with
    superior knowledge and skills relevant to diving operations and
    safety, as well as facilitate their long-term career
    development. We will also continue our practice of structuring
    compensation and benefit plans that are competitive with our
    peers and properly incentivize our workforce.
    Maintain a disciplined cost structure.  We seek
    to contain the costs of our operations and identify new
    opportunities to reduce costs. We believe that our cost
    discipline will enhance our profitability in strong market
    environments and better position us to withstand market
    downturns. Furthermore, the size and diversity of our fleet
    provide meaningful economies of scale and scope advantages,
    which we have realized through the efficient integration of
    recent acquisitions and ongoing cost-savings initiatives.
    Optimize our mix of dayrate and qualified turnkey
    work.  We seek to optimize the allocation of our
    resources between dayrate and qualified turnkey work in order to
    diversify our sources of revenue and enhance overall
    profitability. We believe that this strategy allows us to
    respond effectively to the increasing demand from larger
    customers for integrated solutions while ensuring that a segment
    of our fleet is positioned to capitalize on attractive
    opportunities in the spot market. As business conditions change,
    we will adjust our resource allocation.
    Maintain financial flexibility.  We intend to
    maintain our financial flexibility in the near term by utilizing
    our strong operating cash flows to reduce the debt incurred by
    us in connection with our initial public offering. As of
    December 31, 2006, we had $201 million of outstanding
    debt and $49 million of borrowing capacity, and as of
    June 30, 2007, we had $140 million of outstanding debt
    and $110 million 84




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of borrowing capacity, under our revolving credit agreement,
    which we believe is sufficient to support our business. In
    connection with the merger, we intend to replace this credit
    facility with a new $675 million facility consisting of a
    $375 million senior secured term loan and a
    $300 million senior secured revolving credit facility. We
    intend to achieve a more conservative capital structure over the
    long term so that we may continue to actively pursue
    value-enhancing growth initiatives and mitigate some of the
    financial risk associated with a market downturn.  History
    1980


Acquired International Oilfield
    Divers, our first acquisition in the Gulf of Mexico market1984


Completed a major conversion of
    the Cal Diver I, introducing the first DSV dedicated for
    use in the Gulf of Mexico1986


Began providing subsea
    construction, maintenance and inspection work on a qualified
    turnkey basis, enabling clients to better control project costs1989


Launched shallow water salvage
    business1994


Acquired our first DP DSV, the
    Witch Queen, improving our abilities to operate in winter
    months and work in deeper waters1996


Acquired and enhanced the Uncle
    John, the first semi-submersible MSV dedicated for use in
    the Gulf of Mexico in heavy construction and saturation mode1997


Acquired Aquatica, Inc.
    (previously known as Acadiana Divers) in Lafayette, Louisiana to
    expand our call out diving support capabilities2001


Acquired Professional Divers of
    New Orleans, adding an additional 4 point surface DSV and three
    utility boats2005


Acquired six DSVs and a portable
    saturation diving system from TorchAcquired all of the diving and
    shallow water pipelay business of Acergy operating in the Gulf
    of Mexico and Trinidad, including nine vessels and one portable
    saturation diving system2006


Acquired the business of
    Singapore-based Fraser Diving and its six portable saturation
    diving systems and 15 surface diving systems operating primarily
    in the Middle East, Southeast Asia and AustraliaEntered into a new diving services
    contract with a major oil company, the largest such contract in
    our history based on potential revenues of approximately
    $80 million, for work that we expect to continue through
    2007.     Seasonality
   85




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Customers
    Contracting
    and Tendering
        Competitors
   86




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Employees
  non-U.S. citizens
  Training
    and Safety
    Government
    Regulation
      Environmental
    Regulation
   87




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88




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Properties  Our
    Vessels
   89




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Placed inService by







DP or AnchorFlag State

Cal Dive(1)

Length (Feet)


Berths


MooredSaturation DivingDP DSV Eclipse

Bahamas

3/2002


367



109



DPDP DSV Mystic Viking

Bahamas

6/2001


253



60



DPDP DSV Kestrel

Vanuatu

9/2006


323



80



DPDP MSV Uncle John

Bahamas

11/1996


254



102



DPDSV American Constitution

Panama

11/2005


200



46



4 pointDSV Cal Diver I

U.S.

7/1984


196



40



4 pointDSV Cal Diver II

U.S.

6/1985


166



32



4 pointDSV Midnight Star(2)

Vanuatu

6/2006


197



42



4 pointSurface DivingAmerican Diver

U.S.

11/2005


105



22



American Liberty

U.S.

11/2005


110



22



Cal Diver IV

U.S.

3/2001


120



24



DSV American Star

U.S.

11/2005


165



30



4 pointDSV American Triumph

U.S.

11/2005


164



32



4 pointDSV American Victory

U.S.

11/2005


165



34



4 pointDSV Cal Diver V

U.S.

9/1991


166



34



4 pointDSV Dancer

U.S.

3/2006


173



34



4 pointDSV Mr. Fred

U.S.

3/2000


166



36



4 pointFox

U.S.

10/2005


130



42



Mr. Jack

U.S.

1/1998


120



22



Mr. Jim

U.S.

2/1998


110



19



Polo Pony

U.S.

3/2001


110



25



Sterling Pony

U.S.

3/2001


110



25



White Pony

U.S.

3/2001


116



25



PipelayBrave

U.S.

11/2005


275



80



AnchorRider

U.S.

11/2005


275



80



AnchorDLB801(3)

Panama

1/2006


351



230



Anchor     (1)
    
    Represents the date Cal Dive placed the vessel in service and
    not its date of commissioning.(2)
    
    Expected to be converted in 2008 to full saturation diving
    capabilities.(3)
    
    The DLB801 was purchased in January 2006 and a 50% interest in
    the vessel was subsequently sold to an unaffiliated purchaser
    that same month. The vessel is now under a
    10-year
    charter lease agreement with the purchaser of the 50% interest.
    The charter lease agreement includes an option by the other
    holder to purchase our 50% interest in the vessel beginning in
    January 2009.    Midnight Carrier Seaway Defender Seaway Defender Midnight Carrier Midnight Carrier
 90




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##### Table of Contents



Rider Kestrel Eclipse Mystic
    Viking Uncle John
    Our
    Facilities
  61 2
  Location

Function

SizeHouston, Texas

Corporate Headquarters, Project
    Management and Sales Office

20,000 square feetPort of Iberia, Louisiana

Operations, Offices and Warehouse

23 acres (Buildings: 68,602
    sq. feet)Fourchon, Louisiana

Marine, Operations, Living Quarters

26 acres (Buildings: 2,300
    sq. feet)New Orleans, Louisiana

Sales Office

2,724 square feetSingapore

Marine, Operations, Offices,
    Project Management and Warehouse

29,772 square feetDubai, United Arab Emirates

Sales Office and Warehouse

12,916 square feetPerth, Australia

Operations, Offices and Project
    Management

28,738 square feet  Insurance
    and Legal Proceedings     91




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##### Table of Contents



Market
    for Cal Dives Common Stock and Related Shareholder
    Matters    Common StockPriceHigh


LowFiscal Year 2006Fourth Quarter (from December 14)

$
12.75


$
12.07Fiscal Year 2007First Quarter

$
12.66


$
11.83Second Quarter

$
17.87


$
12.20Third Quarter (through August 10)

$
18.62


$
12.68    Dividend
    Policy   Managements
    Discussion and Analysis of Financial Condition and Results of
    Operations    Our
    Business
    Major
    Influences on Results of Operations
   92




---



##### Table of Contents




    changes in United States and international economic conditions;
    demand for oil and natural gas, especially in the United States,
    China and India;
    worldwide political conditions, particularly in significant
    oil-producing regions such as the Middle East, West Africa and
    Latin America;
    actions taken by OPEC;
    the availability and discovery rate of new oil and natural gas
    reserves in offshore areas;
    the cost of offshore exploration for, and production and
    transportation of, oil and natural gas;
    the ability of oil and natural gas companies to generate funds
    or otherwise obtain external capital for exploration,
    development and production operations;
    the sale and expiration dates of offshore leases in the United
    States and overseas;
    technological advances affecting energy exploration, production,
    transportation and consumption;
    weather conditions;
    environmental or other government regulations; and
    tax policies.     93




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##### Table of Contents



2004


2005


2006


2007Q1


Q2


Q3


Q4


Q1


Q2


Q3


Q4


Q1


Q2


Q3


Q4


Q1


Q2U.S. natural gas prices(1)

$
5.61


$
6.08


$
5.44


$
6.26


$
6.39


$
6.94


$
9.74


$
12.31


$
7.75


$
6.53


$
6.08


$
6.60


$
7.16


$
7.54NYMEX oil prices(2)

$
35.15


$
38.32


$
43.88


$
48.28


$
49.84


$
53.17


$
63.19


$
60.03


$
63.48


$
70.70


$
70.48


$
60.21


$
58.27


$
65.03Gulf of Mexico rigs(3)


117



115



118



122



130



132



130



127



131



132



125



116



116



106Platform installations(4)


25



29



37



28



36



23



19



15



20



30



19



15



17



19Platform removals(4)


23



51



77



39



11



50



44



9



3



14



49



10



18



15Number of our vessels(5)


13



13



13



13



13



13



13



22



23



24



25



25



25



25Our average utilization rate(6)


54
%


57
%


62
%


77
%


65
%


72
%


77
%


94
%


96
%


98
%


91
%


80
%


75
%


77
%     (1)
    
    Quarterly average of the Henry Hub natural gas daily average
    spot price (the midpoint index price per Mmbtu for deliveries
    into a specific pipeline for the applicable calendar day as
    reported by Platts Gas Daily in the Daily Price
    Survey table).(2)
    
    Quarterly average of NYMEX West Texas Intermediate near month
    crude oil daily average contract price.(3)
    
    Average monthly number of rigs contracted, as reported by
    ODS-Petrodata  Offshore Rig Locator.(4)
    
    Source: Minerals Management Service; installation and removal of
    platforms in the Gulf of Mexico.(5)
    
    As of the end of the period and excluding acquired vessels prior
    to their in-service dates, vessels taken out of service prior to
    their disposition and vessels jointly owned by a third party.(6)
    
    Average vessel utilization is calculated by dividing the total
    number of days the vessels generated revenues by the total
    number of days the vessels were available for operation in each
    quarter and does not reflect acquired vessels prior to their
    in-service dates, vessels in drydocking, vessels taken out of
    service for upgrades or prior to their disposition and vessels
    jointly owned by a third party.  Factors
    Impacting Comparability of Our Financial Results
    Recent
    Acquisitions
   94




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##### Table of Contents



DLB801 10-year Kestrel
    Our
    Relationship with Helix
      Critical
    Accounting Estimates and Policies
   95




---



##### Table of Contents



Revenue
    Recognition
        
    the customer provides specifications for the construction of
    facilities or for the provision of related services;
    we can reasonably estimate our progress towards completion and
    our costs;
    the contract includes provisions as to the enforceable rights
    regarding the goods or services to be provided, consideration to
    be received and the manner and terms of payment;
    the customer can be expected to satisfy its obligations under
    the contract; and
    we can be expected to perform our contractual obligations.      Accounts
    Receivable and Allowance for Uncollectible Accounts
   96




---



##### Table of Contents



Related
    Party Cost Allocations
      Property
    and Equipment
    vessel-by-vessel
  12-month
  Recertification
    Costs and Deferred Drydock Charges
  30-month
 97




---



##### Table of Contents



,
  Goodwill
    Equity
    Investment
  Witch Queen.
  Earnings
    per Share
   98




---



##### Table of Contents



Six Months EndedJune 30, 2007Income


SharesEarnings applicable per common
    share  basic

$
41,628



83,680Restricted shares






66Earnings applicable per common
    share  diluted

$
41,628



83,746     Income
    Taxes
    Workers
    Compensation Claims
    Stock-Based
    Compensation Plans
     99




---



##### Table of Contents



Major
    Customers and Concentration of Credit Risk
    Recently
    Issued Accounting Principles
    Accounting for Uncertainty in Income Taxes 
    an Interpretation of FASB Statement No. 109 Accounting for Income
    Taxes
 100




---



##### Table of Contents



Fair Value Measurements.
  The
    Fair Value Option for Financial Assets and Financial Liabilities instrument-by-instrument
  Results
    of Operations
  Comparison
    of Six Months Ended June 30, 2007 and 2006
  Revenues.
  Gross profit.
  Selling and administrative expenses.
  Equity in earnings (loss) of investment, net of
    impairment.
 101




---



##### Table of Contents



Net interest income (expense).
  Income taxes.
  Net income.
  Comparison
    of Years Ended 2006 and 2005
  Revenues.
  Gross profit.
  Selling and administrative expenses.
  Income taxes.
  Net Income.
  Comparison
    of Years Ended 2005 and 2004
  Revenues.
 102




---



##### Table of Contents



Gross profit.
  Selling and administrative expenses.
  Income taxes.
  Net Income.
  Vessel
    Utilization
    Year Ended December 31,


Six Months Ended June 30,2006


2005


2007


2006Number of


Utilization


Number of


Utilization


Number of


Utilization


Number of


UtilizationVessels(1)


(2)


Vessels(1)


(2)


Vessels(1)


(2)


Vessels(1)


(2)Saturation diving


8



92
%


6



91
%


8



91
%


7



95
%Surface and mixed gas diving


15



90
%


14



72
%


15



67
%


15



98
%Shallow water pipelay


2



87
%


2



92
%(3)


2



97
%


2



100
%Entire fleet


25



91
%


22



79
%


25



76
%


24



97
%     (1)
    
    As of the end of the period and excluding acquired vessels prior
    to their in-service dates, vessels taken out of service prior to
    their disposition and vessels jointly owned with a third party.(2)
    
    Effective vessel utilization is calculated by dividing the total
    number of days the vessels generated revenues by the total
    number of days the vessels were available for operation in each
    quarter and does not reflect acquired vessels prior to their
    in-service dates, vessels in drydocking, vessels taken out of
    service for upgrades or prior to their disposition and vessels
    jointly owned with a third party.(3)
    
    Includes activity for only November and December 2005.  Liquidity
    and Capital Resources
   103




---



##### Table of Contents



Cash
    Flows
  Operating activities.
      Investing Activities.
  DLB801 Kestrel
 104




---



##### Table of Contents



DLB801 Kestrel
    Financing activities.
  Capital
    Expenditures
  Kestrel DLB801
  Revolving
    Credit Facility
     105




---



##### Table of Contents



Contractual
    and Other Obligations
        Payments Due by PeriodLess Than








More ThanTotal


1 Year


1-3 Years


3-5 Years


5 Years(In thousands)Payable to Helix

$
8,831


$
3,995


$
2,643


$
1,622


$
571Noncancelable operating leases and
    charters


17,873



8,124



2,672



1,870



5,207Long-term debt


140,000











140,000



Acquisition of Horizon(1)


302,500



302,500











Total cash obligations

$
469,204


$
314,619


$
5,315


$
143,492


$
5,778     (1)
    
    Related to the cash portion of our pending Horizon acquisition.
    We have obtained a commitment for long-term financing to fund
    the cash portion of the acquisition.  Off-Balance
    Sheet Arrangements
  ,
 Market
    Risk Management   106




---



##### Table of Contents



Changes
    in and Disagreements with Accountants on Accounting and
    Financial Disclosure   Directors
    and Executive Officers  Directors
    of Cal Dive
  Name

Age

ClassOwen Kratz


53


I (continuing in office until 2010)David E. Preng


60


I (continuing in office until 2010)William L. Transier


52


II (continuing in office until
    2009)Martin Ferron


50


II (continuing in office until
    2009)Quinn J. Hébert


43


III (continuing in office until
    2008)Todd A. Dittmann


40


III (continuing in office until
    2008)   Owen Kratz
  David E. Preng
  William L. Transier
  Martin Ferron
 107




---



##### Table of Contents



Quinn J. Hébert
  Todd A. Dittmann
  Executive
    Officers of Cal Dive
  Name

Age

PositionQuinn J. Hébert


43


President and Chief Executive
    Officer, DirectorScott T. Naughton


52


Executive Vice President and Chief
    Operating OfficerG. Kregg Lunsford


38


Executive Vice President, Chief
    Financial Officer, and TreasurerLisa Manget Buchanan


47


Vice President, General Counsel,
    and Secretary   Quinn J. Hébert 
  Scott T. Naughton
  G. Kregg Lunsford
 108




---



##### Table of Contents



Lisa Manget Buchanan
 Certain
    Relationships and Related Transactions          12-month
 109




---



##### Table of Contents



step-up
     Board of
    Directors Independence     Compensation
    Committee Interlocks and Insider Participation  Regulation S-K.
 110




---



##### Table of Contents



Compensation
    Discussion and Analysis  Responsibility
    for Our Compensation Program
    Compensation
    Philosophy and Objectives
      
    be competitive with the Companys peer group;
    reflect the complexity/difficulty of the position;
    reflect performance of both the individual and the
    Company; and
    reflect internal fairness within the Company.    
    base salaries, once combined with our annual cash bonus
    opportunity and long term equity incentive grants, should be at
    levels competitive with peer companies that compete with
    Cal Dive for executive talent;
    the annual cash bonus for an executive officer should reflect
    the achievement of Company-wide financial objectives, department
    budget goals and the achievement of personal performance goals
    and objectives; 111




---



##### Table of Contents




    in the event the executive achieves the Company, department and
    personal performance objectives, such executives total
    cash compensation should be at the 50th or
    75th percentile of the members of our peer group with whom
    we compete for executive talent; and
    long-term equity incentive compensation should be at the
    50th or 75th percentile of the peer group based upon
    the complexity of the officers duties and recent
    performance by the individual and the Company.  Design
    of the Compensation Program
      
    40%  achieving personal performance criteria or goals;
    40%  Cal Dive exceeding budgeted pre-tax income
    for the year; and   20%
    Helixs Marine Contracting Services Group (of which
    Cal Dive was a member) exceeding its budgeted pre-tax
    income for the year.     112




---



##### Table of Contents



Compensation
    Consultants
       113




---



##### Table of Contents



Compensation
    Components and Processes
        Base
    Salary.
   114




---



##### Table of Contents



Cash
    Bonus.
      
    40% achieving personal performance criteria or goals;
    40% Cal Dive exceeding budgeted pre-tax income for the
    year; and
    20% Helixs Marine Contracting Services Group (of which
    Cal Dive was a member) exceeding its budgeted pre-tax
    income for the year.    
    40% achieving personal performance criteria or goals; and
    60% the Company exceeding its budgeted pre-tax income for the
    year.       115




---



##### Table of Contents



Long-Term
    Equity Compensation.
          Perquisites.
   116




---



##### Table of Contents



Severance
    Benefits.
    Section 162(m)
    of the Internal Revenue Code.
      Other
    Benefits.
   Director
    Compensation       117




---



##### Table of Contents



Executive
    Compensation  Summary
    Compensation Table
    Non-EquityIncentive Plan


All OtherStock


Option


Compensation


CompensationName and Principal Position

Year


Salary


Bonus(1)


Awards(2)


Awards(2)


(1)(3)


(4)


TotalQuinn J. Hébert


2006


$
250,000


$



$
1,537,868


$



$
200,000


$
7,147


$
1,995,015President and ChiefExecutive OfficerScott T. Naughton


2006



190,000







53,138







185,000



5,500



433,638Executive VicePresident and ChiefOperating OfficerG. Kregg Lunsford


2006



165,000



59,000



39,375



48,880



141,000



10,935



464,190Executive VicePresident and ChiefFinancial OfficerLisa Buchanan(5)


2006



89,060



62,500



15,015











3,729



170,304Vice President,
    GeneralCounsel and
    Secretary     (1)
    
    The compensation reflected is based on 2006s performance
    but was paid in 2007.(2)
    
    Relates to grants of Helix restricted stock and stock options.
    The dollar value of restricted stock and stock options set forth
    in these columns is equal to the compensation cost recognized by
    Helix during 2006 for financial statement purposes in accordance
    with FAS 123R. This valuation method values restricted
    stock and stock options granted during 2006 and previous years.
    A discussion of the assumptions used in calculating the
    compensation cost is set forth in Note 13 to Helixs
    Consolidated Financial Statements included in its 2006 Annual
    Report on
    Form 10-K.
    The only grants of Cal Dive restricted stock to the Named
    Executive Officers were made on December 19, 2006, and
    compensation expense related to such awards was not material to
    the year ended December 31, 2006. See Note 12 to our
    Consolidated and Combined Financial Statements included in our
    2006 Annual Report on
    Form 10-K.(3)
    
    Messrs. Hébert, Naughton and Lunsford were eligible
    for annual cash incentives, based on achievement of certain
    individual performance criteria and corporate profit-sharing
    incentives, under Helixs Senior Management Compensation
    Plan. The actual payments to such officers consisted of bonuses
    based on individual performance objectives together with Cal
    Dive and Helixs Marine Contracting Services Group each
    exceeding certain pre-established pre-tax income goals. The
    exact amount of these annual incentives was determined by the
    Companys Board prior to the Companys initial public
    offering and the establishment of its Compensation Committee.(4)
    
    Consists of matching contributions by the Company through its
    Retirement Plan and the compensation cost computed under
    FAS 123R of purchases of Helix common stock pursuant to the
    Helix Employee Stock Purchase Plan (ESPP). The Companys
    Retirement Plan is a 401(k) retirement savings plan under which
    the Company currently matches 50% of employees pre-tax
    contributions up to 5% of cash compensation (including bonus)
    subject to contribution limits. The Helix ESPP is a qualified,
    non-compensatory plan that allows employees to acquire shares of
    Helix common stock through payroll deductions (limited to 118




---



##### Table of Contents



10% of an employees base salary) over a six-month period.
    The purchase price is equal to 85% of the fair market value of
    the common stock on either the first or last day of the
    subscription period, whichever is lower.(5)
    
    Ms. Buchanans employment with the Company began on
    June 30, 2006.  Grants
    of Plan-Based Awards
        EstimatedFuture


All Other


Grant Date FairPayments of


Stock Awards:


Value ofNon-Equity


No. of Shares


Stock andApproval


Incentive Plans(3)


of Stock or


OptionName

Grant Date


Date


Maximum ($)


Units (#)


Awards ($)(4)Quinn J. Hébert


12/19/06
(1)


12/9/06
(1)

$
200,000



192,307
(1)

$
2,499,991Scott T. Naughton


12/19/06
(1)


12/9/06
(1)


185,000



90,000
(1)


1,170,0001/3/06
(2)


12/13/05
(2)






4,970
(2)


178,373G. Kregg Lunsford


12/19/06
(1)


12/9/06
(1)


141,000



57,153
(1)


742,9891/3/06
(2)


12/13/05
(2)






3,735
(2)


134,049Lisa Buchanan


12/19/06
(1)


12/9/06
(1)


0



52,615
(1)


683,9956/30/06
(2)


6/26/06
(2)






4,180
(2)


150,145     (1)
    
    Represents grant of Cal Dive restricted stock under our 2006
    Plan. The grants are valued based on the offering price in our
    initial public offering of $13.00 per share and became effective
    on the closing date of our initial public offering. A total of
    53% of the Cal Dive restricted stock vests 20% per year over a
    five-year period and the remaining 47% vests 20% per year over a
    five-year period beginning on the first anniversary of the date
    on which Helix no longer owns 51% of our Common Stock. All
    shares vest in full upon a change of control.(2)
    
    Represents grant of Helix restricted stock under the Helix 2005
    Long Term Incentive Plan. Except for the grant to
    Ms. Buchanan, these grants were approved at the December
    meeting of the Helix Compensation Committee to take effect on
    the first business day of the following year based upon the
    closing price of the stock on the last business day of the
    previous year. The grant to Ms. Buchanan was made on
    June 30, 2006, upon the commencement of her employment with
    Cal Dive. The grants are valued based on the fair market value
    on the grant date, which is equal to the closing sale price as
    reported on the New York Stock Exchange on the grant date. The
    Helix restricted stock vests 20% per year over a five-year
    period and all shares vest upon a change of control of Helix.(3)
    
    Reflects maximum payments under Helixs Senior Management
    Compensation Plan, which does not provide for thresholds or
    targets. We are unable to provide a representative target amount
    based on the previous fiscal years performance as we were
    not operated as a separate entity prior to fiscal 2006.(4)
    
    The dollar values of restricted stock are equal to the aggregate
    grant date fair value computed in accordance with FAS 123R.
    A discussion of the assumptions used in calculating the grant
    date fair value is set forth in Note 13 of Helixs
    Consolidated Financial Statements contained in its 2006 Annual
    Report on 119




---



##### Table of Contents



Form 10-K
    and Note 12 of our Consolidated and Combined Financial
    Statements included in our 2006 Annual Report on
    Form 10-K.  Outstanding
    Equity Awards at Fiscal Year-End
    Option Awards


Stock AwardsNo. of


No. ofSecurities


Securities








No. of Shares


Market Value ofUnderlying


Underlying








or Units of


Shares or UnitsUnexercised


Unexercised


Option


Option


Stock That


of Stock ThatOptions (#)


Options (#)


Exercise


Expiration


Have Not


Have NotName

Exercisable


Unexercisable


Price ($)


Date


Vested (#)


Vested ($)Quinn J. Hébert


















41,916
(1)

$
1,314,905















192,307
(2)


2,413,453Scott T. Naughton


10,000







10.94



4/3/11



3,571
(3)


112,02720,000







10.92



2/20/12



4,970
(4)


155,90990,000
(2)


1,129,500G. Kregg Lunsford


8,000



16,000
(5)


8.57



2/17/13



2,570
(3)


80,620















3,735
(4)


117,16757,153
(2)


717,270Lisa Buchanan


















4,180
(6)


131,127















52,615
(2)


660,318     (1)
    
    Shares of Helix restricted stock granted on November 1,
    2005. All shares vested on February 1, 2007.(2)
    
    Shares of Cal Dive restricted stock granted on December 19,
    2006. Shares with respect to 53% vest in annual 20% increments
    over a five-year period, and the balance vests in annual 20%
    increments over a five-year period beginning on the first
    anniversary of the date that Helix no longer owns at least 51%
    of the total voting power of our Common Stock.(3)
    
    Shares of Helix restricted stock granted on January 3,
    2005. The shares vest 20% per year over a five-year period.(4)
    
    Shares of Helix restricted stock granted on January 3,
    2006. The shares vest 20% per year over a five-year period.(5)
    
    Options for Helix common stock were granted February 17,
    2003. The options vest 20% per year over a five-year period.(6)
    
    Shares of Helix restricted stock granted on June 30, 2006.
    The shares vest 20% per year over a five-year period.  Option
    Exercises and Stock Vested
    Stock AwardsNo. of Shares Acquired


Value RealizedName

on Vesting (#)(1)


on Vesting ($)Quinn J. Hébert


16,156


$
552,858G. Kregg Lunsford


642



25,301Scott T. Naughton


893



35,193Lisa M. Buchanan






  120




---



##### Table of Contents



(1)
    
    All shares reported relate to Helix restricted stock. No shares
    of Cal Dive restricted stock vested during 2006.  Employment
    Agreements and Change of Control Provisions Related to Named
    Executive Officers
        gross-up
  Potential
    Payments Upon Termination or Change in Control
     121




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##### Table of Contents



Assumptions and General Principles.
  
    The amounts shown in the table assume that each Named Executive
    Officer was terminated on December 31, 2006.
    A Named Executive Officer is entitled to receive amounts earned
    during his term of employment regardless of the manner in which
    the Named Executive Officers employment is terminated.
    These amounts include base salary and unused vacation pay. These
    amounts are not shown in the table because they are not
    severance payments.
    In general, a Named Executive Officer must continue to be
    employed at the time of payment to be entitled to receive annual
    cash incentive compensation pursuant to our incentive
    compensation plan. In the event a termination occurs prior to
    that time, the Compensation Committee has discretion to award
    the Named Executive Officer an annual cash incentive
    compensation payment that would approximate a prorated amount of
    the payment the Named Executive Officer would have received
    under the plan and takes into consideration the Named Executive
    Officers performance and contributions to achieving the
    performance criteria under the plan to the date of termination.
    Discretionary annual cash incentive compensation payments are
    not typically awarded in the event of a voluntary termination or
    a termination for Cause. In addition, the employment agreements
    with Messrs. Hébert, Naughton and Lunsford
    specifically provide for the payment of a prorated amount of the
    annual cash incentive compensation upon terminations due to the
    death or disability of the Named Executive Officer, prorated to
    the date of such event. We have assumed that the Compensation
    Committee would use its discretion to treat Ms. Buchanan
    the same as the other Named Executive Officers in such events.
    Because we have assumed a December 31, 2006 termination
    date, our Compensation Committee has the discretion to pay each
    of the Named Executive Officers the amount of the annual cash
    incentive payment earned under the plan for 2006, except in
    cases of voluntary termination or termination for Cause.
    Therefore, the amount set forth in the table for annual cash
    incentive compensation payment is the actual annual incentive
    compensation paid to each Named Executive Officer for 2006
    performance. This amount is also the sum of the amounts set
    forth in the Non-Equity Incentive Plan Compensation
    and Bonus columns of the 2006 Summary Compensation
    Table.
    A Named Executive Officer may exercise any stock options that
    are exercisable prior to the date of termination and is entitled
    to receive unrestricted shares of Common Stock with respect to
    any restricted stock awards for which the vesting period has
    expired prior to the date of termination, or, in the case below,
    December 31, 2006. Except for stock options and restricted
    stock that vest upon a change in control, any amounts related to
    these stock options and restricted stock awards are not included
    in the table because they are not severance payments.  Normal and Early Retirement.
  Involuntary Termination.
 122




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##### Table of Contents



12-month
  12-month
  Death and Disability.
  Voluntary Termination and Termination for
    Cause.
  Change in Control.
    Termination of Employment following a Change in
    Control.
  
    Mr. Hébert will receive a lump sum severance payment
    in an amount equal to two times (a) his base salary during
    the year prior to termination together with (b) an amount
    equal to the annual cash incentive compensation received by
    Mr. Hébert for the last complete year of employment; 123




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##### Table of Contents




    Mr. Naughton will receive a lump sum severance payment in
    an amount equal to two times (a) his base salary plus
    (b) the annual cash incentive compensation paid to
    Mr. Naughton for his last complete year of employment;
    Mr. Lunsford will receive a lump sum severance payment in
    an amount equal to one times (in the case of a termination
    without Cause following a change in control), or two
    times (in the case of a termination by    
    two years of continued participation in the Companys
    health care and life insurance benefit plans; and
    an amount equal to the excise tax and taxes thereon charged, if
    any, to the Named Executive Officer as a result of any change in
    control payments.   124




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##### Table of Contents



ESTIMATED
    PAYMENTS ON TERMINATION OR CHANGE IN CONTROL
  Event

Q. Hébert


S. Naughton


G. K. Lunsford


L. BuchananNormal and Early
    Retirement2006 annual cash incentive
    compensation

$
200,000


$
185,000


$
200,000


$
62,500Total

$
200,000


$
185,000


$
200,000


$
62,500Death2006 annual cash incentive
    compensation

$
200,000


$
185,000


$
200,000


$
62,500Total

$
200,000


$
185,000


$
200,000


$
62,500Disability2006 annual cash incentive
    compensation

$
200,000


$
185,000


$
200,000


$
62,500Total

$
200,000


$
185,000


$
200,000


$
62,500Voluntary Termination and
    Termination for CauseNo payments


N/A



N/A



N/A



N/ATotal


N/A



N/A



N/A



N/AInvoluntary Termination Without
    Cause2006 annual cash incentive
    compensation

$
200,000


$
185,000


$
200,000


$
62,500Continued base salary


208,333



190,000



165,000



0Continued cash incentive
    compensation


166,667



185,000



200,000



0Continued health, disability and
    life insurance benefits


10,426



2,916



7,796



0Continued vesting of Helix stock
    options


0



0



182,400



0Continued vesting of Helix
    restricted stock


1,314,905



59,195



43,573



0Continued vesting of Cal Dive
    restricted stock


0



119,727



76,030



0Total

$
1,900,331


$
741,838


$
874,799


$
62,500Change in ControlAccelerated Helix stock options

$
0


$
0


$
364,800


$
0Accelerated Helix restricted stock


1,314,905



267,931



197,788



131,126Accelerated Cal Dive restricted
    stock


2,413,453



1,129,500



717,270



660,318Total

$
3,728,358


$
1,397,431


$
1,279,858


$
791,444Change in Control with
    Involuntary Termination Without Cause2006 annual cash incentive
    compensation

$
200,000


$
185,000


$
200,000


$
0Cash severance payment


900,000



750,000



365,000



0Accelerated Helix stock options


0



0



364,800



0Accelerated Helix restricted stock


1,314,905



267,931



197,788



131,126Accelerated Cal Dive restricted
    stock


2,413,453



1,129,500



717,270



660,318Continued health, disability and
    life insurance benefits


20,852



5,832



15,593



0Excise tax gross up


1,142,037



684,002



357,491



0Total

$
5,991,247


$
3,022,265


$
2,217,942


$
791,444Change in Control with
    Termination by Executive With Good Cause2006 annual cash incentive
    compensation

$
200,000


$
185,000


$
200,000


$
0Cash severance payment


900,000



750,000



730,000



0Accelerated Helix stock options


0



0



364,800



0Accelerated Helix restricted stock


1,314,905



267,931



197,788



131,126Accelerated Cal Dive restricted
    stock


2,413,453



1,129,500



717,270



660,318Continued health, disability and
    life insurance benefits


20,852



5,832



15,593



0Excise tax gross up


1,142,037



684,002



525,115



0Total

$
5,991,247


$
3,022,265


$
2,750,566


$
791,444  125




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##### Table of Contents



Beneficial
    Ownership of Cal Dives Common Stock  Rule 13d-3
  Percentage ofNumber of Shares


OutstandingName of Beneficial Owner

Beneficially Owned


Common StockOwen Kratz


10,000



*Martin R. Ferron


10,000



*Quinn J. Hébert


193,447



*Todd A. Dittmann


12,481



*David E. Preng


12,201



*William L. Transier


8,298



*G. Kregg Lunsford


57,153



*Scott T. Naughton


90,000



*Lisa M. Buchanan


53,315



*Helix Energy Solutions Group,
    Inc.


61,506,691



72.94
%400 N. Sam Houston
    Parkway, E.Suite 400Houston, Texas 77060All executive officers and
    directors as a group (9 persons)


446,895



*     *
    
    Less than 1%. 126




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##### Table of Contents



INFORMATION
    ABOUT HORIZON General
    Development of Horizons Business      
    laying, burying or repairing marine pipelines;
    providing
    hook-up and
    commissioning services;
    installing offshore production platforms and other
    structures; and
    disassembling and salvaging offshore production platforms and
    other structures.    Maximum


MaximumDerrick


PipelayLength


Lift


DiameterVessel(1)

Vessel Type

(Feet)


(Tons)


(Inches)American Horizon

Pipelay/Pipebury


180







18Lone Star Horizon

Pipelay/Pipebury


320







39Brazos Horizon

Pipelay/Pipebury


210







18Pecos Horizon

Pipelay/Pipebury


250







24Canyon Horizon

Pipebury


330







Atlantic Horizon

Derrick


420



550



Pacific Horizon

Derrick


350



1,000



Sea Horizon

Derrick/Pipelay


360



1,200



36Texas Horizon

Diving Support/Pipelay and
    Dynamically Positioned


341







10     (1)
    
    Fire destroyed the Gulf Horizon pipelay/pipebury barge in 2004.
    The vessel is inactive in Port Arthur and Horizon has no plans
    to repair it.     127




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##### Table of Contents



Canyon Horizon Canyon Horizon
  Pacific Horizon Atlantic Horizon
  Sea Horizon Sea Horizon
  Texas Horizon
     Directors
    and Executive Officers  Form 10-K,
 Beneficial
    Ownership of Horizons Common Stock  Form 10-K,
 128




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##### Table of Contents



CAL
    DIVES FINANCIAL STATEMENTS AND SUPPLEMENTARY
    DATA  PageAudited Financial
    StatementsReport of
    Independent Registered Public Accounting Firm


130Consolidated and
    Combined Balance Sheets as of December 31, 2006 and
    2005


131Consolidated and
    Combined Statements of Operations for the Years Ended
    December 31, 2006, 2005 and 2004


132Consolidated and
    Combined Statements of Changes in Stockholders Equity for
    the Years Ended December 31, 2006, 2005 and 2004


133Consolidated and
    Combined Statements of Cash Flows for the Years Ended
    December 31, 2006, 2005 and 2004


134Notes to
    Consolidated and Combined Financial Statements


135Interim Financial
    StatementsCondensed
    Consolidated Balance Sheets as of June 30, 2007 (unaudited)
    and December 31, 2006 (audited)


154Condensed
    Consolidated and Combined Statements of Operations for the Three
    and Six Months Ended June 30, 2007 and 2006


155Condensed
    Consolidated and Combined Statements of Cash Flows for the Six
    Months Ended June 30, 2007 and 2006


156Notes to Condensed
    Consolidated and Combined Financial Statements


157  129




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##### Table of Contents



Report of
    Independent Registered Public Accounting Firm                 130




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##### Table of Contents



Cal Dive
    International, Inc. and Subsidiaries
  Consolidated and Combined Balance Sheets
  December 31,2006


2005(In thousands)ASSETSCurrent assets:Cash and cash equivalents

$
22,655


$
Accounts receivable Trade, net of allowance for
    doubtful accounts $169 and $26, respectively


93,748



75,713Unbilled revenue


33,869



13,608Net receivable from Helix


1,626



Deferred income taxes


1,869



1,939Assets held for sale


698



7,936Notes receivable


3,008



1,500Other current assets


11,274



9,788Total current assets


168,747



110,484Property and equipment


293,929



173,841Less  Accumulated
    depreciation


(71,682
)


(60,237
)222,247



113,604Other assets:Equity investment


10,871



11,513Goodwill


26,666



27,814Other assets, net


23,622



14,469Total assets

$
452,153


$
277,884LIABILITIES AND
    STOCKHOLDERS EQUITYCurrent liabilities:Accounts payable

$
39,810


$
32,034Accrued liabilities


19,004



41,835Total current liabilities


58,814



73,869Long-term debt


201,000



Long-term payable to Helix


11,028



Deferred income taxes


20,824



22,621Other long term liabilities


2,726



3,611Total liabilities


294,392



100,101Commitments and contingencies






Stockholders equity:Common stock, 240,000 shares
    authorized, $0.01 par value,Issued and outstanding:
    84,298 shares in 2006, no shares issued in 2005


843



Capital in excess of par value of
    common stock


154,898



Helixs net investment






179,681Retained earnings


2,020



Unearned compensation






(1,898
)Total stockholders equity


157,761



177,783Total liabilities and
    stockholders equity

$
452,153


$
277,884    131




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##### Table of Contents



Cal Dive
    International, Inc. and Subsidiaries
  Consolidated and Combined Statements of Operations
  Year Ended December 31,2006


2005


2004(In thousands, except per share amounts)Net revenues

$
509,917


$
224,299


$
125,786Cost of sales


287,387



152,586



101,583Gross profit


222,530



71,713



24,203Gain on sale of assets


349



270



Selling and administrative expenses


37,431



16,730



12,318Income from operations


185,448



55,253



11,885Equity in earnings (losses) of
    investment


(487
)


2,817



Net interest income


163



45



Income before income taxes


185,124



58,115



11,885Provision for income taxes


65,710



20,385



4,211Net Income

$
119,414


$
37,730


$
7,674Net income per common share:Basic and diluted net income per
    share

$
1.91


$
0.61


$
0.12Weighted average basic and diluted
    shares outstanding


62,600



61,507



61,507    132




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##### Table of Contents



Cal Dive
    International, Inc. and Subsidiaries
  Consolidated and Combined Statements of Changes in
    Stockholders Equity
  CommonHelixs


Stock,


Capital








TotalNet


$.01 par


in Excess


Retained


Unearned


StockholdersInvestment


Value


of Par


Earnings


Compensation


Equity(In thousands)Balances at December 31, 2003

$
110,532














$



$
110,532Net income


7,674



















7,674Capital contributions by Helix


2,912



















2,912Cash transfers to Helix


(28,610
)


















(28,610
)Balances at December 31, 2004

$
92,508














$



$
92,508Net income


37,730



















37,730Stock grants in Helixs stock
    plan


2,124















(2,124
)


Amortization of stock grants in
    Helixs stock plan


















226



226Capital contributions by Helix


79,547



















79,547Cash transfers to Helix


(32,228
)


















(32,228
)Balances at December 31, 2005

$
179,681














$
(1,898
)

$
177,783Reversal of unearned compensation


(1,898
)














1,898



Amortization of stock grants in
    Helixs stock plan


2,930



















2,930Net income prior to IPO


117,394



















117,394Capital contributions by Helix
    prior to IPO


121,157



















121,157Cash transfers to Helix prior to
    IPO


(64,784
)


















(64,784
)Contributed capital related to
    Helix deferred tax asset


1,261



















1,261Dividends to Helix


(464,401
)


















(464,401
)Capitalization of Cal Dive
    International, Inc.


108,660



615



(109,275
)










Restricted share grants






6



(6
)










Net proceeds from initial public
    offering






222



264,179











264,401Net income subsequent to IPO














2,020







2,020Balances at December 31, 2006

$



$
843


$
154,898


$
2,020


$



$
157,761    133




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##### Table of Contents



Cal Dive
    International, Inc. and Subsidiaries
  Consolidated and Combined Statements of Cash Flows
  Year Ended December 31,2006


2005


2004(In thousands)Cash Flows From Operating
    Activities:Net income

$
119,414


$
37,730


$
7,674Adjustments to reconcile net
    income to net cash provided by operating activities:Depreciation and amortization


24,515



15,308



15,510Asset impairment charges






790



3,900Equity in (earnings) loss of
    investment


487



(2,817
)Stock compensation expense


2,930



226Deferred income taxes


11,737



11



(970
)Gain on sale of assets


(349
)


(270
)Changes in operating assets and
    liabilities:Accounts receivable, net


(38,105
)


(55,305
)


54Other current assets


(5,281
)


(3,494
)


258Accounts payable and accrued
    liabilities


(10,081
)


46,431



6,272Other noncurrent, net


(18,828
)


(6,382
)


(4,088
)Net cash provided by operating
    activities:


86,439



32,228



28,610Cash Flows From Investing
    Activities:Capital expenditures


(38,086
)


(36,407
)


(2,912
)Acquisition of businesses


(100,128
)


(42,917
)Equity investment


155



(1,696
)Loan to Offshore Technology
    Solutions Limited






(1,500
)Proceeds from sales of property


16,902



2,973Net cash used in investing
    activities:


(121,157
)


(79,547
)


(2,912
)Cash Flows From Financing
    Activities:Draws on credit facility


201,000Proceeds from initial public
    offering


264,401Dividends paid to Helix


(464,401
)Cash transfers from Helix for
    investing activities


121,157



79,547



2,912Cash transfers to Helix from
    operating activities


(64,784
)


(32,228
)


(28,610
)Net cash provided by (used in)
    financing activities


57,373



47,319



(25,698
)Net increase in cash and cash
    equivalents


22,655







Cash and cash equivalents:Balance, beginning of year










Balance, end of year

$
22,655


$



$
    134




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##### Table of Contents



Cal Dive
    International, Inc. and Subsidiaries
  Notes to Consolidated and Combined Financial
    Statements
  1.
    Organization
    and Basis of Presentation              2.
    Summary
    of Significant Accounting Policies  Principles
    of Consolidation and Combination
   135




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##### Table of Contents



Cal Dive
    International, Inc. and Subsidiaries
  Notes to
    Consolidated and Combined Financial
    Statements  (Continued)
    Use of
    Estimates
    Revenue
    Recognition
        
    the customer provides specifications for the construction of
    facilities or for the provision of related services;
    we can reasonably estimate our progress towards completion and
    our costs;
    the contract includes provisions as to the enforceable rights
    regarding the goods or services to be provided, consideration to
    be received and the manner and terms of payment;
    the customer can be expected to satisfy its obligations under
    the contract; and
    the Company can be expected to perform its contractual
    obligations.   136




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##### Table of Contents



Cal Dive
    International, Inc. and Subsidiaries
  Notes to
    Consolidated and Combined Financial
    Statements  (Continued)
      Accounts
    Receivable and Allowance for Uncollectible
    Accounts
    Property
    and Equipment
    Estimated


December 31,Useful Life


2006


2005Vessels


15 to 20 years


$
232,678


$
142,036Portable saturation diving
    systems, machinery and equipment


5 to 10 years



55,798



25,749Buildings and leasehold
    improvements


4 to 20 years



5,453



6,056Total property and equipment





$
293,929


$
173,841      137




---



##### Table of Contents



Cal Dive
    International, Inc. and Subsidiaries
  Notes to
    Consolidated and Combined Financial
    Statements  (Continued)
    12-month
  Recertification
    Costs and Deferred Drydock Charges
  30-month
    Goodwill
    Equity
    Investment
   138




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##### Table of Contents



Cal Dive
    International, Inc. and Subsidiaries
  Notes to
    Consolidated and Combined Financial
    Statements  (Continued)
    Income
    Taxes
    Earnings
    Per Share
    Stock-Based
    Compensation Plans
   139




---



##### Table of Contents



Cal Dive
    International, Inc. and Subsidiaries
  Notes to
    Consolidated and Combined Financial
    Statements  (Continued)
    Year EndedDecember 31,2005


2004Net income as reported

$
37,730


$
7,674Plus: Stock-based employee
    compensation cost included in reported net income


226



Less: Total stock-based
    compensation costs determined under the fair value method


(576
)


(1,087
)Pro forma net income

$
37,380


$
6,587Basic and diluted net income per
    share:As reported

$
0.61


$
0.12Pro forma

$
0.61


$
0.11     Major
    Customers and Concentration of Credit Risk
    Statement
    of Cash Flow Information
    Recently
    Issued Accounting Principles
   140




---



##### Table of Contents



Cal Dive
    International, Inc. and Subsidiaries
  Notes to
    Consolidated and Combined Financial
    Statements  (Continued)
        3.
    Related
    Party Transactions       141




---



##### Table of Contents



Cal Dive
    International, Inc. and Subsidiaries
  Notes to
    Consolidated and Combined Financial
    Statements  (Continued)
             142




---



##### Table of Contents



Cal Dive
    International, Inc. and Subsidiaries
  Notes to
    Consolidated and Combined Financial
    Statements  (Continued)
    step-up
  4.
    Acquisition
    of Torch Offshore, Inc. Assets    5.
    Acquisition
    of Acergy (formerly known as Stolt Offshore) Business     143




---



##### Table of Contents



Cal Dive
    International, Inc. and Subsidiaries
  Notes to
    Consolidated and Combined Financial
    Statements  (Continued)
    Vessels

$
94,484Goodwill


11,693Portable saturation system and
    diving equipment


9,494Facilities, land and leasehold
    improvements


4,314Customer relationship intangible
    asset


3,698Materials and supplies


631Total

$
124,314     10-year
  10-year
    Year EndedDecember 31,2005


2004Net revenues

$
464,543


$
287,717Income (loss) before income taxes

$
64,136


$
(24,645
)Net income (loss)

$
41,644


$
(16,071
)   6.
    Acquisition
    of Fraser Diving International Ltd (FDI)
    Business   144




---



##### Table of Contents



Cal Dive
    International, Inc. and Subsidiaries
  Notes to
    Consolidated and Combined Financial
    Statements  (Continued)
    Portable saturation diving systems
    and surface diving systems

$
23,685Diving support equipment, support
    facilities and other equipment


3,004Cash and cash equivalents


2,332Accounts receivable


1,817Prepaid expenses and deposits


691Total assets acquired


31,529Accounts payable and accrued
    liabilities


(2,243
)Net assets acquired

$
29,286     7.
    Equity
    Investment         145




---



##### Table of Contents



Cal Dive
    International, Inc. and Subsidiaries
  Notes to
    Consolidated and Combined Financial
    Statements  (Continued)
      8.
    Accrued
    Liabilities    Year EndedDecember 31,2006


2005Accrued payroll and related
    benefits

$
7,500


$
5,370Accrued insurance


3,367



3,172Insurance claims to be reimbursed


1,870



2,678Accrued income taxes payable


1,201



20,374Deposits






10,000Other


5,066



241Total accrued liabilities

$
19,004


$
41,835   9.
    Long-term
    Debt       146




---



##### Table of Contents



Cal Dive
    International, Inc. and Subsidiaries
  Notes to
    Consolidated and Combined Financial
    Statements  (Continued)
    10.
    Income
    Taxes      Year EndedDecember 31,2006


2005


2004Current

$
53,973


$
20,374


$
5,181Deferred


11,737



11



(970
)$
65,710


$
20,385


$
4,211       Year EndedDecember 31,2006


2005


2004Statutory rate


35.0
%


35.0
%


35.0
%Other


0.5



0.1



0.4Effective rate


35.5
%


35.1
%


35.4
%  147




---



##### Table of Contents



Cal Dive
    International, Inc. and Subsidiaries
  Notes to
    Consolidated and Combined Financial
    Statements  (Continued)
    December 31,2006


2005Deferred tax liabilities:Depreciation

$
20,770


$
19,506Deferred drydock costs


7,024



2,894Prepaid and other


831



1,555Total deferred tax liabilities

$
28,625


$
23,955Deferred tax assets:Allowance for doubtful accounts

$
(292
)

$
(646
)Reserves, accrued liabilities and
    other


(9,378
)


(2,627
)Total deferred tax assets

$
(9,670
)

$
(3,273
)Net deferred tax liability

$
18,955


$
20,682       
    Liability for Taxes.  Each party has agreed to
    indemnify the other in respect of all taxes for which it is
    responsible under the Tax Matters Agreement. Helix is generally
    responsible for all federal, state, local and foreign income
    taxes that are imposed on or are attributable to the Company or
    any of its subsidiaries for all tax periods (or portions
    thereof) ending on or before the Companys initial public
    offering (or December 14, 2006). The Company is generally
    responsible for all federal, state, local and foreign income
    taxes that are imposed on or are attributable to the Company or
    any of its subsidiaries for all tax periods (or portions
    thereof) beginning after its initial public offering (or
    December 14, 2006). The Company is also responsible for all
    taxes other than income taxes imposed on or attributable to the
    Company or any of its subsidiaries for all tax periods.
    Tax Benefit Payments.  As a result of certain
    taxable income recognition by Helix in conjunction with the
    Companys initial public offering, the Company will become
    entitled to certain tax benefits that are expected to be
    realized by the Company in the ordinary course of its business
    and otherwise would not have been available to the Company.
    These benefits are generally attributable to increased tax
    deductions for amortization of tangible and intangible assets
    and to increased tax basis in nonamortizable assets. Under the
    Tax Matters Agreement, for the next ten years, the Company will
    be required to make annual payments to Helix equal to 90% of the
    amount of taxes which the Company saves for each tax period as a
    result of these increased tax benefits. The timing of the
    Companys payments to Helix under the Tax Matters Agreement
    will be determined with reference to when the Company actually
    realizes the projected tax savings. This timing will depend
    upon, among other things, the amount of our taxable income and
    the timing at which certain assets are sold or disposed. At
    December 31, 2006, this tax benefit is $12.6 million
    and is included as a component of non-current deferred income
    taxes. At December 31, 2006, a corresponding current
    payable and long-term payable 148




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##### Table of Contents



Cal Dive
    International, Inc. and Subsidiaries
  Notes to
    Consolidated and Combined Financial
    Statements  (Continued)
  of $0.3 million and $11.0 million, respectively, to
    Helix is reflected in these consolidated and combined financial
    statements.  
    Preparation and Filing of Tax Returns.  Helix
    will prepare and file all income tax returns that include the
    Company or any of its subsidiaries if Helix is responsible for
    any portion of the taxes reported on such tax returns. The Tax
    Matters Agreement also provides that Helix will have the sole
    authority to respond to and conduct all tax proceedings
    (including tax audits) relating to such income tax returns.  11.
    Commitments
    and Contingencies  Lease
    Commitments
      Insurance
      Litigation
    and Claims
   149




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##### Table of Contents



Cal Dive
    International, Inc. and Subsidiaries
  Notes to
    Consolidated and Combined Financial
    Statements  (Continued)
    12.
    Employee
    Benefit Plans  Defined
    Contribution Plan
    Stock-Based
    Compensation Plans
  Helix
    Plans
       150




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##### Table of Contents



Cal Dive
    International, Inc. and Subsidiaries
  Notes to
    Consolidated and Combined Financial
    Statements  (Continued)
              Cal
    Dive Plans
     151




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##### Table of Contents



Cal Dive
    International, Inc. and Subsidiaries
  Notes to
    Consolidated and Combined Financial
    Statements  (Continued)
    2006Shares


Fair Value(1)Restricted shares outstanding at
    beginning of year






Granted


618,321


$
13.00Vested






Forfeited






Balance at end of year


618,321


$
13.00     (1)
    
    Represents the average grant date market value.      13.
    Allowance
    for Uncollectible Accounts    Year Ended December 31,2006


2005


2004Beginning balance

$
26


$
4,641


$
5,087Additions


603



411



1,225Deductions


(460
)


(5,026
)


(1,671
)Ending balance

$
169


$
26


$
4,641     14.
    Business
    Segment Information   152




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##### Table of Contents



Cal Dive
    International, Inc. and Subsidiaries
  Notes to
    Consolidated and Combined Financial
    Statements  (Continued)
    15.
    Quarterly
    Financial Information (Unaudited)    Quarter EndedMarch 31


June 30


September 30


December 31(In thousands, except per share data)Fiscal 2006 Revenues

$
119,790


$
124,765


$
128,363


$
136,999Gross profit


50,206



60,944



57,737



53,643Net income applicable to common
    shareholders

$
30,774


$
33,420


$
29,051


$
26,169Weighted Avg. Shares Outstanding:Basic and diluted


61,507



61,507



61,507



65,845Earnings per common share:Basic and diluted

$
0.50


$
0.54


$
0.47


$
0.40Fiscal 2005 Revenues

$
37,292


$
40,699


$
49,246


$
97,062Gross profit


12,406



8,794



17,667



32,846Net income applicable to common
    shareholders

$
6,245


$
3,733


$
10,120


$
17,632Weighted Avg. Shares Outstanding:Basic and diluted


61,507



61,507



61,507



61,507Earnings per common share:Basic and diluted

$
0.10


$
0.06


$
0.16


$
0.29  153




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##### Table of Contents



Cal Dive
    International, Inc. and Subsidiaries
  Condensed Consolidated Balance Sheets
  June 30,


December 31,2007


2006(Unaudited)(In thousands, except per share par value)ASSETSCurrent assets:Cash and cash equivalents

$
3,667


$
22,655Accounts
    receivable Trade, net of allowance for
    doubtful accounts of $0 and $169, respectively


101,777



93,748Unbilled revenue


22,948



33,869Net receivable from Helix


869



1,626Deferred income taxes


2,626



1,869Assets held for sale






698Notes receivable


1,814



3,008Other current assets


19,689



11,274Total current assets


153,390



168,747Property and equipment


308,433



293,929Less  Accumulated
    depreciation


(82,398
)


(71,682
)226,035



222,247Other assets:Equity investment






10,871Goodwill


26,802



26,666Other assets, net


39,381



23,622Total assets

$
445,608


$
452,153LIABILITIES AND
    STOCKHOLDERS EQUITYCurrent liabilities:Accounts payable

$
49,497


$
39,810Accrued liabilities


15,821



19,004Total current liabilities


65,318



58,814Long-term debt


140,000



201,000Long-term payable to Helix


8,392



11,028Deferred income taxes


29,137



20,824Other long term liabilities


1,769



2,726Total liabilities


244,616



294,392Commitments and contingencies






Stockholders equity:Common stock, 240,000 shares
    authorized, $0.01 par value, issued and outstanding: 84,327
    and 84,298 shares, respectively


843



843Capital in excess of par value of
    common stock


156,501



154,898Retained earnings


43,648



2,020Total stockholders equity


200,992



157,761Total liabilities and
    stockholders equity

$
445,608


$
452,153    154




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##### Table of Contents



Cal Dive
    International, Inc. and Subsidiaries
  Condensed Consolidated and Combined Statements of Operations
  Three Months Ended


Six Months EndedJune 30,


June 30,2007


2006


2007


2006(Unaudited)(In thousands, except per share amounts)Net revenues

$
135,258


$
124,764


$
284,484


$
244,554Cost of sales


89,693



63,821



180,967



133,405Gross profit


45,565



60,943



103,517



111,149Gain on sale of assets


1,687



16



1,694



283Selling and administrative expenses


11,110



9,360



20,766



15,515Income from operations


36,142



51,599



84,445



95,917Equity in earnings (losses) of
    investment, inclusive of impairment charge


(11,793
)


(183
)


(10,841
)


2,650Net interest income (expense)


(2,419
)


(13
)


(4,958
)


316Income before income taxes


21,930



51,403



68,646



98,883Provision for income taxes


10,365



17,983



27,018



34,689Net income

$
11,565


$
33,420


$
41,628


$
64,194Earnings per common share:Basic

$
0.14


$
0.54


$
0.50


$
1.04Diluted

$
0.14


$
0.54


$
0.50


$
1.04Weighted average common shares
    outstanding:Basic


83,680



61,507



83,680



61,507Diluted


83,801



61,507



83,746



61,507    155




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##### Table of Contents



Cal Dive
    International, Inc. and Subsidiaries
  Condensed Consolidated and Combined Statements of Cash
    Flows
  Six Months Ended June 30,2007


2006(Unaudited)(In thousands)Cash Flows From Operating
    Activities:Net income

$
41,628


$
64,194Adjustments to reconcile net
    income to net cash provided by operating activities:Depreciation and amortization


18,074



10,727Stock compensation expense


1,603



1,122Equity in (earnings) losses of
    investment, inclusive of impairment charge


10,841



(2,650
)Deferred income taxes


7,556



2,175Gain on sale of assets


(1,694
)


(283
)Changes in operating assets and
    liabilities:Accounts receivable, net


4,518



(32,472
)Assets held for sale


698



Other current assets


(9,506
)


1,211Accounts payable and accrued
    liabilities


1,872



10,450Other noncurrent, net


(21,823
)


(7,452
)Net cash provided by operating
    activities


53,767



47,022Cash Flows From Investing
    Activities:Capital expenditures


(12,272
)


(7,387
)Acquisition of businesses






(78,174
)Proceeds from sales of property


517



16,782Net cash used in investing
    activities


(11,755
)


(68,779
)Cash Flows From Financing
    Activities:Repayments on credit facility


(61,000
)


Cash transfers from Helix for
    investing activities






79,800Cash transfers to Helix from
    operating activities






(58,039
)Net cash provided by (used in)
    financing activities


(61,000
)


21,761Net increase (decrease) in cash
    and cash equivalents


(18,988
)


4Cash and cash equivalents:Balance, beginning of period


22,655



Balance, end of period

$
3,667


$
4Supplemental Cash Flow Information:Interest paid

$
5,685


$
Income taxes paid

$
26,205


$
    156




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##### Table of Contents



Cal Dive
    International, Inc. and Subsidiaries
  Notes to Condensed Consolidated and Combined Financial
    Statements (unaudited)
  1.
    Preparation
    of Interim Financial Statements            Form 10-K
 157




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##### Table of Contents



Cal Dive
    International, Inc. and Subsidiaries
  Notes to Condensed Consolidated and Combined Financial
    Statements  (Continued)
  Form 10-K. Form 10-K.
  2.
    Related
    Party Transactions               158




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##### Table of Contents



Cal Dive
    International, Inc. and Subsidiaries
  Notes to Condensed Consolidated and Combined Financial
    Statements  (Continued)
  step-up
  3.
    Details
    of Certain Accounts (in thousands)    June 30,


December 31,2007


2006Other receivables

$
3,764


$
3,134Insurance claims to be reimbursed


3,902



1,870Other prepaids


3,304



1,679Income taxes receivable


5,849



Supplies and spare parts inventory


2,790



2,295Other


80



2,296$
19,689


$
11,274     June 30,


December 31,2007


2006Deferred drydock expenses, net

$
31,141


$
20,069Equipment deposits


4,375



Intangible assets with definite
    lives, net


2,928



3,159Deferred financing costs


397



378Other


540



16$
39,381


$
23,622     June 30,


December 31,2007


2006Accrued payroll and related
    benefits

$
6,025


$
7,500Accrued insurance


4,698



3,367Insurance claims to be reimbursed


3,902



1,870Accrued income taxes payable






1,201Other


1,196



5,066$
15,821


$
19,004   4.
    Equity
    Investment   159




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##### Table of Contents



Cal Dive
    International, Inc. and Subsidiaries
  Notes to Condensed Consolidated and Combined Financial
    Statements  (Continued)
    5.
    Long-term
    Debt      6.
    Commitments
    and Contingencies  Lease
    Commitments
    Insurance
    Litigation
    and Claims
   160




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##### Table of Contents



Cal Dive
    International, Inc. and Subsidiaries
  Notes to Condensed Consolidated and Combined Financial
    Statements  (Continued)
    7.
    Stock-Based
    Compensation Plans  Helix
    Plans
          Cal
    Dive Plans
       161




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##### Table of Contents



Cal Dive
    International, Inc. and Subsidiaries
  Notes to Condensed Consolidated and Combined Financial
    Statements  (Continued)
          8.
    Income
    Taxes      non-U.S. jurisdictions. non-U.S. jurisdiction
  9.
    Business
    Segment Information   162




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##### Table of Contents



Cal Dive
    International, Inc. and Subsidiaries
  Notes to Condensed Consolidated and Combined Financial
    Statements  (Continued)
    10.
    Recently
    Issued Accounting Principles    The
    Fair Value Option for Financial Assets and Financial Liabilities instrument-by-instrument
  11.
    Acquisition
    of Horizon Offshore, Inc.    12.
    Earnings
    Per Share    Three Months Ended


Six Months EndedJune 30,


June 30,2007


2007Income


Shares


Income


SharesEarnings applicable per common
    share  Basic

$
11,565



83,680


$
41,628



83,680Restricted shares






121







66Earnings applicable per common
    share  Diluted

$
11,565



83,801


$
41,628



83,746    163




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##### Table of Contents



UNAUDITED
    CONDENSED COMBINED PRO FORMA FINANCIAL DATA



The following unaudited pro forma financial statements combine
    the historical consolidated balance sheets and statements of
    operations of Cal Dive and Horizon, giving effect to the
    merger using the purchase method of accounting.



We are providing the information to aid you in your analysis of
    the financial aspects of the merger. The historical statements
    of operations for the year ended December 31, 2006 were
    derived from the audited financial statements of Cal Dive
    and Horizon contained in each companys Annual Report on
    Form 10-K
    for the fiscal year ended December 31, 2006, which reports
    are included in this information statement/proxy
    statement/prospectus, in the case of Cal Dive, or
    incorporated into this information statement/proxy
    statement/prospectus by reference, in the case of Horizon. The
    historical unaudited statements of operations for the six months
    ended June 30, 2007, and the historical unaudited balance
    sheets as of June 30, 2007, were derived from the unaudited
    financial statements of Cal Dive and Horizon contained in
    each companys Quarterly Report on
    Form 10-Q
    for the period ended June 30, 2006, which reports are
    included in this information statement/proxy
    statement/prospectus, in the case of Cal Dive, or
    incorporated into this information statement/proxy
    statement/prospectus by reference, in the case of Horizon.
    You should read the following unaudited pro forma combined
    financial statements together with the historical financial
    statements and related notes contained elsewhere in this
    information statement/proxy statement/prospectus or incorporated
    by reference into this information statement/proxy
    statement/prospectus.



The unaudited pro forma combined statements of operations
    assumes the merger was effected on January 1, 2006. The
    unaudited pro forma combined balance sheet gives effect to the
    merger as if it had occurred on June 30, 2007. Horizon uses
    the units-of-production method to calculate depreciation on its
    barges, vessels and related equipment, while Cal Dive uses
    the straight-line method for its vessels. The pro forma
    financial data includes adjustments to reflect the Horizon
    depreciation on its barges, vessels and related equipment using
    the straight-line method over the estimated useful lives of the
    respective assets. The remaining accounting policies for
    Cal Dive and Horizon are comparable.



The unaudited pro forma combined information is for illustrative
    purposes only. The financial results may have been different had
    the companies always been combined. Further, the unaudited pro
    forma combined financial statements do not reflect the effect of
    asset dispositions, if any, that may be required by order of
    regulatory authorities; restructuring charges that will be
    incurred to fully integrate and operate the combined
    organization more efficiently or anticipated synergies resulting
    from the merger. Expected costs associated with the combination
    of the companies operations, such as severance costs for
    redundant functions, integrating information technology systems
    and other arrangements, are in the process of being evaluated by
    Cal Dive. These costs are not expected to exceed
    $25 million, of which approximately $12.4 million
    relates to additional purchase price consideration for change in
    control payments for Horizon executive officers. You should not
    rely on the pro forma combined financial information as being
    indicative of the historical results that would have been
    achieved had the companies always been combined or the future
    results that Cal Dive will experience.

164




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##### Table of Contents



Cal Dive
    International, Inc.
  Unaudited
    Condensed Combined Pro Forma Statement of Operations for the
 Year
    Ended December 31, 2006
  Cal Dive andPro Forma


Horizon Pro FormaCal Dive


Horizon*


Adjustments


Combined(In thousands, except per share amounts)Net revenues

$
509,917


$
547,289


$
(16,228
)(a)

$
1,040,978Cost of sales:Operating expenses


262,872



373,786



(16,228
)(a)


620,430Depreciation and amortization


24,515



26,254



3,989
(b)


54,758Gross profit


222,530



147,249



(3,989
)


365,790(Gain) loss on sale of assets and
    insurance settlement, reserves and impairments


(349
)


4,258







3,909Selling and administrative expenses


37,431



33,167







70,598Income from operations


185,448



109,824



(3,989
)


291,283Equity in earnings of investment


(487
)










(487
)Net interest income (expense) and
    other


163



(13,399
)


(13,049
)(c)


(26,285
)Income before income taxes


185,124



96,425



(17,038
)


264,511Provision for income taxes


65,710



29,415



(5,963
)(d)


89,162Net income

$
119,414


$
67,010


$
(11,057
)

$
175,349Earnings per common share:Basic

$
1.91


$
2.18






$
2.11Diluted

$
1.91


$
2.14






$
2.11Weighted average common shares
    outstandingBasic


62,600



30,712



(10,276
)(e)


83,036Diluted


62,600



31,263



(10,827
)(e)


83,036     *
    
    Certain amounts have been reclassified to conform to Cal
    Dives presentation.(a)
    
    Reflects the elimination of sales and related operating expenses
    between Cal Dive and Horizon.(b)
    
    Reflects (i) estimated increases in depreciation and
    amortization related to the
    step-up
    of the acquired assets to their fair value of $7.3 million
    and (ii) an adjustment of $3.3 million to decrease
    Horizon depreciation to reflect depreciation calculations under
    the straight-line method instead of the units-of-production
    method used by Horizon. Adjustment calculated as the incremental
    depreciation based on the purchase price applied to 2006 for
    Horizon using the straight-line method. Adjustment assumes no
    material changes in the estimated useful lives for acquired
    assets as a result of the preliminary purchase price allocation.(c)
    
    Reflects the increase in long-term debt to fund the cash portion
    of the purchase price at estimated annual interest rate of 7.45%
    for the year ended December 31, 2006 (based upon the terms
    of the proposed credit facilities of three month LIBOR plus
    225 basis points   see Proposed
    Financings on page 178 of this information
    statement/proxy statement/prospectus). A 1/8% increase in the
    average three month LIBOR rate would increase pre-tax interest
    expense by approximately $401,000 for the year ended
    December 31, 2006.(d)
    
    The pro forma adjustment to income tax reflects the statutory
    federal and state income tax impacts of the pro forma
    adjustments to Cal Dives pretax income with an applied tax
    rate of 35%.(e)
    
    Pro forma weighted average shares outstanding have been adjusted
    to reflect the conversion of Horizons outstanding common
    stock to shares of Cal Dive common stock (at a rate of one
    Horizon share for 0.625 Cal Dive share) assuming the transaction
    was consummated at the beginning of the period presented. 165




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##### Table of Contents



Cal Dive
    International, Inc.
  Unaudited
    Condensed Combined Pro Forma Statement of Operations for the
    Six
 Months
    Ended June 30, 2007
  Cal Dive andPro Forma


Horizon Pro FormaCal Dive


Horizon*


Adjustments


Combined(In thousands, except per share amounts)Net revenues

$
284,484


$
204,066


$
(8,609
)(a)

$
479,941Cost of sales:Operating expenses


163,124



178,824



(8,609
)(a)


333,339Depreciation and amortization


17,843



11,134



4,538
(b)


33,515Gross profit


103,517



14,108



(4,538
)


113,087(Gain) loss on sale of assets


(1,694
)










(1,694
)Selling and administrative expenses


20,766



16,096







36,862Income (loss) from operations


84,445



(1,988
)


(4,538
)


77,919Equity in earnings (loss) of
    investment


(10,841
)










(10,841
)Net interest income (expense) and
    other


(4,958
)


(3,922
)


(9,899
)(c)


(18,779
)Income (loss) before income taxes


68,646



(5,910
)


(14,437
)


48,299Provision for income taxes


27,018



(1,944
)


(5,053
)(d)


20,021Net income (loss)

$
41,628


$
(3,966
)

$
(9,384
)

$
28,278Earnings (loss) per common share:Basic

$
0.50


$
(0.12
)





$
0.27Diluted

$
0.50


$
(0.12
)





$
0.27Weighted average common shares
    outstandingBasic


83,680



31,920



(11,484
)(e)


104,116Diluted


83,746



31,920



(11,484
)(e)


104,182     *
    
    Certain amounts have been reclassified to conform to Cal
    Dives presentation.(a)
    
    Reflects the elimination of sales and related operating expenses
    between Cal Dive and Horizon.(b)
    
    Reflects (i) estimated increases in depreciation and
    amortization related to the
    step-up
    of the acquired assets to their fair value of $3.6 million
    and (ii) an adjustment of $0.9 million to increase
    Horizon depreciation to reflect depreciation calculations under
    the straight-line method instead of the units-of-production
    method used by Horizon. Adjustment calculated as the incremental
    depreciation based on the purchase price applied to the first
    six months of 2007 for Horizon using the straight-line method.
    Adjustment assumes no material changes in the estimated useful
    lives for acquired assets as a result of the preliminary
    purchase price allocation.(c)
    
    Reflects the increase in long-term debt to fund the cash portion
    of the purchase price at estimated annual interest rate of 7.61%
    for the six month period ended June 30, 2007 (based upon
    the terms of the proposed credit facilities of three month LIBOR
    plus 225 basis points  see Proposed
    Financings on page 178 of this information
    statement/proxy statement/prospectus). A 1/8% increase in the
    average three month LIBOR rate would increase pre-tax interest
    expense by approximately $297,000 for the six months ended
    June 30, 2007.(d)
    
    The pro forma adjustment to income tax reflects the statutory
    federal and state income tax impacts of the pro forma
    adjustments to Cal Dives pretax income with an applied tax
    rate of 35%.(e)
    
    Pro forma weighted average shares outstanding have been adjusted
    to reflect the conversion of Horizons outstanding common
    stock to shares of Cal Dive common stock (at a rate of one
    Horizon share for 0.625 Cal Dive share) assuming the transaction
    was consummated at the beginning of the period presented. 166




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##### Table of Contents



Cal Dive
    International, Inc.
  Unaudited
    Condensed Combined Pro Forma Balance Sheet as of June 30,
    2007
  Cal Dive andPro Forma


Horizon Pro FormaCal Dive


Horizon*


Adjustments


Combined(In thousands)ASSETSCurrent assets:Cash and cash equivalents

$
3,667


$
81,860


$
(69,971
)(a),(b)

$
15,556Short-term investments






19,125



(19,125
)(b)


Restricted cash






9,543







9,543Accounts receivable -Trade, net


101,777



102,735



(1,254
)(f)


203,258Costs in excess of billings






100,914







100,914Unbilled revenue


22,948







(4,415
)(f)


18,533Net receivable from Helix


869











869Income tax receivable






1,040







1,040Deferred income taxes


2,626











2,626Notes receivable


1,814











1,814Other current assets


19,689



6,706







26,395Total current assets


153,390



321,923



(94,765
)


380,548Net property and equipment


226,035



199,260



130,740
(a)


556,035Other assets:Contract receivables, long-term






13,851







13,851Goodwill


26,802







283,527
(a),(d)


310,329Other assets, net


39,381



16,198



(10,448
)(e)


45,131Total assets

$
445,608


$
551,232


$
309,054


$
1,305,894LIABILITIES AND
    STOCKHOLDERS EQUITYCurrent liabilities:Accounts payable

$
49,497


$
17,975


$



$
67,472Accrued liabilities


15,821



91,590



6,694
(g)


114,105Billings in excess of costs






19,559







19,559Current maturities of long-term
    debt






13,837



(13,837
)(b)


Current taxes payable






7,155







7,155Total current liabilities


65,318



150,116



(7,143
)


208,291Long-term debt, net of current
    maturities


140,000



93,283



241,290
(b)


474,573Long-term payable to Helix


8,392











8,392Deferred income taxes


29,137



12,429



45,759
(d)


87,325Other long term liabilities


1,769



436







2,205Total liabilities


244,616



256,264



279,906



780,786Total stockholders equity


200,992



294,968



29,148
(c)


525,108Total liabilities and
    stockholders equity

$
445,608


$
551,232


$
309,054


$
1,305,894  167




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##### Table of Contents



*
    
    Certain amounts have been reclassified to conform to Cal
    Dives presentation.(a)
    
    The following is a preliminary estimate of the deemed purchase
    price for Horizon on a purchase accounting basis, and takes into
    account the merger consideration of $9.25 in cash plus 0.625 of
    a share of Cal Dive common stock for each of Horizons
    32,697,655 estimated diluted shares of common stock (which
    includes shares of restricted stock which will become fully
    vested at the effective time of the merger):  (In thousands)Cash

$
302,45332,697,655 Horizon estimated
    diluted shares times $9.25 per shareCal Dive Stock


324,11632,697,655 Horizon estimated
    diluted shares times 0.625 times $15.86 per share (which
    represents the weighted-average price of Cal Dive common stock
    for a
    five-day
    period beginning two available trading days before the
    announcement of the merger)Transaction Related
    Costs


14,096Estimated direct transactions fees
    payable by Cal Dive to be capitalized as part of the purchase
    price for Horizon (including legal fees, underwriting fees,
    accounting fees, early termination fees on Horizon debt and
    other fees)Total Purchase Price

$
640,665Purchase Price
    AllocationCurrent assets

$
321,923Property and equipment


330,000Other long-term assets


19,601Goodwill


283,527Current liabilities


(162,479
)Deferred income taxes and other
    long term liabilities


(58,624
)Long-term debt, net of current
    maturities


(93,283
)$
640,665         (b)
    
    Reflects the following debt retirement and debt refinancing to
    occur in conjunction with this merger: (i) the retirement
    of all Horizon long-term debt, inclusive of the current portion
    of long-term debt, (ii) $75 million of cash, cash
    equivalents and short-term investments balances used for
    retirement of Horizon long-term debt, and (iii) increase in
    long-term debt to retire remaining portion of Horizon debt and
    fund the cash 168




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##### Table of Contents



portion of the purchase price at estimated interest rate of
    three month LIBOR plus 225 basis points (based upon the
    terms of the proposed credit facilities  see
    Proposed Financings on page 178 of this
    information statement/proxy statement/prospectus), which
    averaged 7.45% for 2006 and 7.61% for the six months ended
    June 30, 2007.(c)
    
    Reflects the elimination of book value of Horizon equity and the
    issuance of 20.4 million shares of Cal Dive common stock to
    be issued to Horizon stockholders as consideration in the
    acquisition.(d)
    
    Reflects the deferred tax
    gross-up
    relating to the acquired property and equipment based on
    purchase price paid. A combined statutory federal and blended
    state income tax rate of 35.0% was used for this adjustment.(e)
    
    Reflects (i) the write-off of capitalized drydock costs for
    the Horizon barges of $13.5 million, (ii) the
    capitalization of deferred financing costs estimated to be
    $5.2 million for the proposed credit facilities referred to
    in note (b) above, and (iii) the write-off of deferred
    financing costs of $2.1 million for prepayment of Horizon
    debt to be retired.(f)
    
    Reflects the elimination of accounts receivable and unbilled
    revenue between Cal Dive and Horizon.(g)
    
    Reflects the elimination of accrued liabilities between Cal Dive
    and Horizon and the estimated accrual for change of control
    payments to be made to the Horizon executive officers of
    $12.4 million. DESCRIPTION
    OF CAL DIVE CAPITAL STOCK     Common
    Stock     Preferred
    Stock    
    the designation of the series;
    the number of shares of the series, which number
    Cal Dives board of directors may thereafter increase
    or decrease (but not below the number of shares thereof then
    outstanding);
    whether dividends, if any, will be cumulative or noncumulative
    and the dividend rate of the series; 169




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##### Table of Contents




    the dates at which dividends, if any, will be payable;
    the redemption rights and price or prices, if any, for shares of
    the series;
    the terms and amount of any sinking fund provided for the
    purchase or redemption of shares of the series;
    the amounts payable on, and the preferences, if any, of shares
    of the series in the event of any voluntary or involuntary
    liquidation, dissolution or winding up of the affairs of
    Cal Dive;
    whether the shares of the series shall be convertible into
    shares of any other class or series, or any other security, of
    Cal Dive or any other entity, and, if so, the specification
    of such other class or series of such other security, the
    conversion price or prices or rate or rates, any adjustments
    thereof, the date or dates at which such shares shall be
    convertible and all other terms and conditions upon which such
    conversion may be made;
    restrictions on the issuance of shares of the same series or of
    any other class or series; and
    the voting rights, if any, of the holders of shares of the
    series.    
    restricting dividends on Cal Dives common stock;
    diluting the voting power of Cal Dives common stock;
    impairing the liquidation rights of Cal Dives common
    stock; or
    delaying or preventing a change in control of Cal Dive
    without further action by its stockholders.   Purposes
    and Effects of Certain Provisions of Cal Dives Amended and
    Restated Certificate of Incorporation and Bylaws      Classified
    Board of Directors; Removal of Directors
   170




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Preferred
    Stock
      Stockholder
    Action by Written Consent
    Amendment
    of Cal Dives Bylaws
   171




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##### Table of Contents



Amendment
    of Certain Provisions of Cal Dives Amended and Restated
    Certificate of Incorporation
    Stockholder
    Meetings
    Requirements
    for Advance Notification of Stockholder Nominations and
    Proposals
    Delaware
    Anti-Takeover Law
     172




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##### Table of Contents



No
    Cumulative Voting
   Limitation
    on Foreign Ownership of Common Stock   Corporate
    Opportunity   Transfer
    Agent and Registrar   New York
    Stock Exchange Listing   COMPARISON
    OF STOCKHOLDERS RIGHTS   173




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Cal Dive

HorizonApplicable State Takeover
    Laws

Cal Dives amended and
    restated certificate of incorporation provides that Helix shall
    not be deemed to be an interested stockholder
    within the meaning of Section 203 of the DGCL until Helix
    beneficially owns less than 15% of Cal Dives common stock
    and subsequently increases its shareholdings to once again
    beneficially own at least 15% of Cal Dives common stock.
    Otherwise, Cal Dive is governed by Section 203 of the DGCL.

Horizon is governed by Section 203
    of the DGCL.Amendments to
    Bylaws

Cal Dives amended and
    restated certificate of incorporation and bylaws provide that
    the provisions of its bylaws relating to the calling of meetings
    of stockholders, notice of meetings of stockholders, stockholder
    action by written consent, advance notice of stockholder
    business or director nominations, the authorized number of
    directors, the classified board structure, the filling of
    director vacancies or the removal of directors (and any
    provision relating to the amendment of any of these provisions)
    may only be amended by the vote of a majority of its entire
    board of directors or, as long as Helix and its subsidiaries
    (excluding Cal Dive and its subsidiaries) own shares
    representing at least a majority of the votes entitled to be
    cast by the outstanding capital stock in the election of Cal
    Dives board of directors, by the vote of holders of a
    majority of the votes entitled to be cast by outstanding capital
    stock in the election of its board of directors. Once Helix and
    its subsidiaries (excluding Cal Dive and its subsidiaries) cease
    to own shares representing at least a majority of the votes
    entitled to be cast by the outstanding capital stock in the
    election of its board of directors, Cal Dives amended and
    restated certificate of incorporation and bylaws provide

Horizons bylaws provide that
    the board of directors will have the power to alter or repeal
    the bylaws upon the affirmative vote of majority of the entire
    board. Horizons bylaws also provide that they may be
    altered or repealed by the stockholders upon the affirmative
    vote of holders of not less than the majority of the outstanding
    capital stock entitled to vote generally in the election of
    directors. 174




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##### Table of Contents



Cal Dive

Horizonthat these provisions may only be
    amended by the vote of a majority of Cal Dives entire
    board of directors or by the vote of holders of at least 80% of
    the votes entitled to be cast by the outstanding capital stock
    in the election of its board of directors.Amendments to Certificate of
    Incorporation

Cal Dives amended and
    restated certificate of incorporation and amended and restated
    bylaws provide that the provisions of its amended and restated
    certificate of incorporation relating to the calling of meetings
    of stockholders, notice of meetings of stockholders, stockholder
    action by written consent, advance notice of stockholder
    business or director nominations, the authorized number of
    directors, the classified board structure, the filling of
    director vacancies or the removal of directors (and any
    provision relating to the amendment of any of these provisions)
    may only be amended with approval by holders of shares
    representing at least a majority of the votes entitled to be
    cast by the outstanding capital stock in the election of Cal
    Dives board of directors, as long as Helix and its
    subsidiaries (excluding Cal Dive and its subsidiaries) own
    shares representing at least a majority of the votes entitled to
    be cast by the outstanding capital stock in the election of Cal
    Dives board of directors.  Once Helix and its subsidiaries
    (excluding Cal Dive and its subsidiaries) cease to own shares
    representing at least a majority of the votes entitled to be
    cast by the outstanding capital stock in the election of Cal
    Dives board of directors, Cal Dives amended and
    restated certificate of incorporation and amended and restated
    bylaws provide that these provisions may only be amended by the
    vote of a majority of its entire board of directors followed by
    the vote of holders of at least 80% of the votes entitled to be
    cast by the outstanding capital stock in the election of its
    board of directors.

Horizons certificate of
    incorporation may be amended in accordance with Delaware law,
    which requires the board of directors to adopt a resolution
    setting forth the amendment to the certificate of incorporation
    and to declare its advisability before the stockholders may vote
    thereon.  Delaware law further provides that amendments to the
    certificate of incorporation generally require the approval of
    the holders of a majority of the outstanding stock entitled to
    vote thereon, and if the amendment would increase or decrease
    the number of authorized shares of any class or series or the
    par value of such shares or would adversely affect the rights,
    powers or preferences of such class or series, a majority of the
    outstanding stock of such class or series also must approve the
    amendment.Action By Stockholders Without
    a Meeting

Cal Dives amended and
    restated certificate of incorporation permits its stockholders
    to act by written consent

Horizons bylaws provide that
    any action which was to be taken at any meeting of holders of
    capital stock, 175




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##### Table of Contents



Cal Dive

Horizonwithout a meeting as long as
    Helix and its subsidiaries (excluding Cal Dive and its
    subsidiaries) continue to beneficially own shares representing
    at least a majority of the votes entitled to be cast by the
    outstanding capital stock in the election of Cal Dives
    board of directors.  Once Helix and its subsidiaries (excluding
    Cal Dive and its subsidiaries) cease to beneficially own at
    least a majority of the votes entitled to be cast by the
    outstanding capital stock in the election of Cal Dives
    board of directors, Cal Dives amended and restated
    certificate of incorporation eliminates the right of its
    stockholders to act by written consent.

may be taken without a meeting,
    without prior notice and without a vote, if a consent in
    writing, setting forth the action so taken, shall be signed by
    holders of capital stock that would be entitled to vote thereon
    if an annual or special meeting had been called for the taking
    of such action, having at least the minimum number of votes that
    would be necessary to take such action at a meeting of all
    holders of capital stock entitled to vote thereon.Ability to Call Special
    Meetings

Cal Dives amended and
    restated certificate of incorporation and amended and restated
    bylaws provide that a special meeting of its stockholders may be
    called only by (i) Helix, so long as Helix and its subsidiaries
    (excluding Cal Dive and its subsidiaries) beneficially own at
    least a majority of the votes entitled to be cast by the
    outstanding capital stock in the election of Cal Dives
    board of directors, or (ii) the chairman of Cal Dives
    board of directors or upon the vote of the majority of Cal
    Dives board of directors.

Horizons bylaws permit a
    special meeting of stockholders to be called by (i) the chairman
    of Horizons board of directors or (ii) upon a vote of the
    majority of Horizons board of directors.Classified Board; Removal of
    Directors

Cal Dives directors are
    currently divided into three classes, only one class of which is
    subject to re- election in any given year.  In addition, Cal
    Dives amended and restated certificate of incorporation
    provides that directors may be removed, with or without cause,
    by the affirmative vote of shares representing a majority of the
    votes entitled to be cast by the outstanding capital stock in
    the election of Cal Dives board of directors as long as
    Helix and its subsidiaries (excluding Cal Dive and its
    subsidiaries) owns shares representing at least a majority of
    the votes entitled to be cast by the outstanding capital stock
    in the election of directors.  Once Helix and its subsidiaries
    (excluding Cal Dive and its subsidiaries) cease to own shares
    representing at least a majority of the votes entitled to be
    cast by the outstanding capital stock in the

Horizons organizational
    documents do not provide for a classified board.  Neither
    Horizons certificate of incorporation nor its bylaws alter
    the rule under Delaware law that a director of a corporation may
    be removed with or without cause by the affirmative vote of a
    majority of shares entitled to vote for the election of
    directors.  Accordingly, Horizons directors may be removed
    with or without cause by the affirmative vote of a majority of
    shares entitled to vote for the election of directors. 176




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Cal Dive

Horizonelection of Cal Dives board
    of directors, Cal Dives amended and restated certificate
    of incorporation requires that directors may only be removed for
    cause and only then by the affirmative vote of not less than 80%
    of votes entitled to be cast by the outstanding capital stock in
    the election of its board of directors.Vacancies on Board of
    Directors

Cal Dives amended and
    restated bylaws provide that newly created directorships
    resulting from any increase in the authorized number of
    directors or any vacancies in Cal Dives board of directors
    resulting from death, resignation, retirement, disqualification,
    removal from office or other cause shall be filled, subject to
    any rights of preferred stock, solely by the affirmative vote of
    a majority of the remaining directors then in office, even
    though less than a quorum of the board of directors, or by the
    sole remaining director; provided, however, that, until Helix
    and its subsidiaries (excluding Cal Dive and its subsidiaries)
    cease to beneficially own shares representing a majority of the
    votes entitled to be cast by the outstanding capital stock in
    the election of Cal Dives board of directors, if such
    vacancy was caused by an action of the stockholders, such
    vacancy shall be filled only by the by the affirmative vote of
    holders of a majority of the votes entitled to be cast by
    outstanding capital stock in the election of its board of
    directors.

Horizons organizational
    documents follow the provisions of Delaware law, which state
    that a vacancy on a corporations board of directors or a
    newly created directorship resulting from any increase in the
    authorized number of directors may be filled by a majority of
    the directors then in office, although less than a quorum.Limitation or Elimination of
    Directors Personal
    Liability

Cal Dives amended and
    restated certificate of incorporation contains a provision
    eliminating the personal liability of its directors for breach
    of fiduciary duty as a director, subject to the foregoing
    limitations.

Horizons certificate of
    incorporation contains a provision eliminating the personal
    liability of its directors for breach of fiduciary duty as a
    director, subject to the foregoing limitations.Indemnification and
    Insurance

Cal Dives amended and
    restated certificate of incorporation and amended and restated
    bylaws provide for indemnification of officers and directors to
    the fullest extent permitted by Delaware law.

The bylaws of Horizon provide for
    indemnification of officers and directors to the fullest extent
    permitted by Delaware law.Inspection of Stockholder
    Lists

Cal Dives amended and
    restated bylaws follow the provisions of Delaware law, which
    state that any stockholder, upon written demand under oath
    stating the purpose of the

Horizons bylaws follow the
    provisions of Delaware law, which state that any stockholder,
    upon written demand under oath stating the purpose of the
    demand, has the right during the usual 177




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##### Table of Contents



Cal Dive

Horizondemand, has the right during the
    usual hours for business to inspect for any proper purpose a
    list of the corporations stockholders and to make copies
    of or extracts from the list.  In addition, Cal Dives
    amended and restated bylaws also specifically provide that, as
    long as Helix and its subsidiaries (excluding Cal Dive and its
    subsidiaries) own shares representing at least a majority of the
    votes entitled to be cast by the outstanding capital stock in
    the election of directors, upon the request of Helix, the stock
    list shall be provided to Helix promptly.

hours for business to inspect for
    any proper purpose a list of the corporations stockholders
    and to make copies of or extracts from the list.  PROPOSED
    FINANCINGS   LEGAL
    MATTERS   EXPERTS    Form 10-K
   178




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##### Table of Contents



STOCKHOLDER
    PROPOSALS  Rule 14a-8 Rule 14a-8 non-Rule 14a-8
 WHERE YOU
    CAN FIND MORE INFORMATION      1-800-SEC-0330
      http://www.sec.gov http://www.CalDive.com http://www.horizonoffshore.com.
   179




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##### Table of Contents



Horizon
    Securities and Exchange Commission Filings
  Commission
    file number:
    001-16857
  
    Horizons Annual Report on
    Form 10-K
    for the fiscal year ended December 31, 2006 filed on
    March 15, 2007.
    Horizons Quarterly Report on
    Form 10-Q
    for the fiscal quarter ended March 31, 2007 filed on
    May 10, 2007.
    Horizons Quarterly Report on
    Form 10-Q
    for the fiscal quarter ended June 30, 2007 filed on
    August 7, 2007.
    Horizons Current Reports on
    Form 8-K
    filed on January 5, 2007, February 1, 2007,
    February 5, 2007, March 14, 2007, April 5, 2007,
    May 11, 2007, May 24, 2007, June 12, 2007,
    June 15, 2007 and June 21, 2007.   180




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##### Table of Contents



ANNEX A  Agreement and Plan of Merger dated as of June 11,
    2007
   AGREEMENT
    AND PLAN OF MERGER
    DATED AS OF JUNE 11, 2007
    BY AND AMONG
    CAL DIVE INTERNATIONAL, INC.,
    CAL DIVE ACQUISITION, LLC
    AND
    HORIZON OFFSHORE, INC.




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##### Table of Contents



TABLE OF
    CONTENTS
  PageARTICLE I THE MERGER


A-11.1

The Merger


A-11.2

Effective Time of the Merger


A-11.3

Effects of the Merger


A-11.4

Closing


A-11.5

Certificate of Formation


A-11.6

Limited Liability Company Agreement


A-11.7

Managers and Officers


A-2ARTICLE II CONSIDERATION/
    EXCHANGE PROCEDURES


A-22.1

Effect of the Merger on Capital
    Stock


A-22.2

Dissenting Shares


A-22.3

Stock Options and Equity Awards


A-32.4

Surrender and Payment


A-32.5

No Fractional Shares


A-42.6

Lost Certificates


A-52.7

Withholding Rights


A-52.8

No Further Ownership Rights in
    Company Common Stock


A-52.9

Investment of Cash by the Exchange
    Agent


A-52.10

Further Assurances


A-52.11

Shares Held by Company Affiliates


A-5ARTICLE III REPRESENTATIONS AND
    WARRANTIES


A-63.1

Representations and Warranties of
    the Company


A-63.2

Representations and Warranties of
    Cal Dive


A-15ARTICLE IV COVENANTS RELATING TO
    CONDUCT OF BUSINESS


A-244.1

Covenants of the Company


A-244.2

Covenants of Cal Dive


A-264.3

Governmental Filings


A-274.4

No Control of Other Partys
    Business


A-28ARTICLE V ADDITIONAL AGREEMENTS


A-285.1

Preparation of Information
    Statement/Proxy Statement/Prospectus; Stockholders Meeting


A-285.2

Access to Information


A-295.3

Required Actions


A-305.4

Acquisition Proposals


A-315.5

Fees and Expenses


A-335.6

Directors and Officers
    Indemnification and Insurance


A-335.7

Employee Benefits; Retention Plan


A-335.8

Public Announcements


A-345.9

Listing of Shares of Cal Dive
    Common Stock


A-345.10

Affiliates


A-345.11

Section 16 Matters


A-345.12

Tax Matters


A-345.13

Vessel Matters


A-35 A-i




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##### Table of Contents



PageARTICLE VI CONDITIONS PRECEDENT


A-356.1

Conditions to Each Partys
    Obligation to Effect the Merger


A-356.2

Additional Conditions to
    Obligations of Cal Dive


A-356.3

Additional Conditions to
    Obligations of the Company


A-36ARTICLE VII TERMINATION


A-367.1

Termination


A-367.2

Effect of Termination


A-37ARTICLE VIII CERTAIN DEFINITIONS


A-38ARTICLE IX GENERAL PROVISIONS


A-459.1

Non-Survival of Representations,
    Warranties and Agreements


A-459.2

Notices


A-459.3

Interpretation


A-469.4

Counterparts


A-469.5

Entire Agreement; No Third Party
    Beneficiaries


A-469.6

Governing Law


A-469.7

Severability


A-469.8

Assignment


A-479.9

Submission to Jurisdiction; Waivers


A-479.10

Enforcement


A-479.11

Amendment


A-479.12

Extension; Waiver


A-47   LIST OF
    EXHIBITS
  Exhibit

TitleExhibit A


Form of Affiliate Agreement


A-49  A-ii




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##### Table of Contents



Agreement (Cal Dive (Merger
    Sub Company
  W I T N E
    S S E T H:
  Merger Surviving Company
  Plan of
    Merger
      ARTICLE I
  THE MERGER
  The Merger.
  Effective Time of the
    Merger. Certificate of Merger Effective
    Time
  Effects of the Merger.
  Closing. Closing Article VI Closing
    Date
  Certificate of Formation.
  Limited Liability Company
    Agreement.
 A-1




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##### Table of Contents



Managers and Officers.
  ARTICLE II
  CONSIDERATION/
    EXCHANGE PROCEDURES
  Effect of the Merger on Capital
    Stock.
  Article II Section 2.2 Merger Consideration
  Per Share Cash Amount Exchange Ratio Section 2.1(c)
  Article II Certificate Section 2.5
    Section 2.1(d)
    Dissenting
    Shares. Dissenting
    Share Section 262
 A-2




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##### Table of Contents



Section 262 Section 262
  Stock Options and Equity Awards.
  Company Stock Option Converted Cal Dive Option Section 2.3 Section 2.3(a)
    Section 2.3 Section 2.3
  Surrender and Payment.
  Exchange Agent
 A-3




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##### Table of Contents



Section 2.1(a) Section 2.3(a) (b), Section 2.5 Section 2.5 Exchange
    Fund.
  Section 2.1 Section
    2.1 Article II Section 2.5
    Article II
  Section 2.4
  Section 2.4
  No Fractional Shares. Section 2.4
 A-4




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##### Table of Contents



Lost Certificates. Article II
  Withholding Rights. Article II
  No Further Ownership Rights in Company Common
    Stock. Article II Section 2.4 2.5
  Investment of Cash by the Exchange
    Agent. Article II
  Further Assurances.
  Shares Held by Company
    Affiliates. Section 5.10) Section 5.10
 A-5




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##### Table of Contents



ARTICLE III
  REPRESENTATIONS
    AND WARRANTIES
  Representations and Warranties of the
    Company. Section 9.3(a) Sections 3.1(f) (o)
  Corporate Organization
      Capitalization
    Section
    3.1(b) Section 3.1(b)
 A-6




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##### Table of Contents



Section 3.1(e)(v)
  Authority; No Violation
  Company Stockholders Meeting Company Stockholder
    Approval
  Section 3.1(d)
  Consents and Approvals. Information Statement/Proxy
    Statement/Prospectus
 A-7




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##### Table of Contents



Company Necessary Consents
  Financial Reports and SEC Documents
  Form 10-K Company SEC
    Documents
  Rules 13a-15(e) 15d-15(e)
 A-8




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##### Table of Contents



Section 3.1(e)(v) Section 3.1(e)(v)
  Absence of Undisclosed
    Liabilities. 10-Q
  Absence of Certain Changes or
    Events.
         A-9




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##### Table of Contents



Section 5.7(b)
    Legal Proceedings. Section 3.1(h)
  Compliance with Applicable Law.
  Environmental Liability.
  Employee Benefit Plans; Labor Matters
  Section
    3.1(k)
 A-10




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##### Table of Contents



A-11




---



##### Table of Contents



Section 3.1(k) Section 3.1(k)
  Section 3.1(k)
  Taxes
           A-12




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##### Table of Contents



and/or
    Contracts
  Regulation S-K Section 3.1(m) Company
    Contract Regulation S-K
    Title to Properties
  Section 3.1(c)(v)
 A-13




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##### Table of Contents



Insurance. Section 3.1(o)
  Reorganization under the Code. Sections 6.2(c) 6.3(c)
  State Takeover Statutes; Absence of Supermajority
    Provision.
  Opinion of Financial Advisor.
  Board Approval.
  Brokers Fees.
  Ownership of Cal Dive Capital
    Stock.
  Vessel Related Matters
  Section 3.1(v)(i)(A)(I)
    and/or
     A-14




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##### Table of Contents



and/or
      Certain Business Practices.
  Representations and Warranties of
    Cal Dive. Section 9.3(a) Sections 3.2(f) (m)
  Corporate Organization
       A-15




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##### Table of Contents



Capitalization
  Section 3.2(b)(i)
  Section
    3.2(b)(ii) Section 3.2(b)(ii) 10-Q,
  Authority; No Violation
   A-16




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##### Table of Contents



Section 3.2(d)
  Consents and Approvals. Form S-4 Form S-4, Form S-4 Cal Dive Necessary
    Consents
  Financial Reports and SEC Documents
  Form 10-K Cal Dive SEC
    Documents
 A-17




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##### Table of Contents



Rules 13a-15(e) 15d-15(e)
      Section 3.2(e)(v) Section 3.2(e)(v)
 A-18




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##### Table of Contents



Absence of Undisclosed
    Liabilities. 10-Q
  Absence of Certain Changes or
    Events.
        Section 3.2(b)(i)
    Legal
    Proceedings. Section 3.2(h)
  Compliance with Applicable
    Law.
  Environmental Liability.
 A-19




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##### Table of Contents



Employee Benefit Plans; Labor Matters
  Section
    3.2(k)
         A-20




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##### Table of Contents



Taxes
     A-21




---



##### Table of Contents



and/or
  Contracts
  Regulation S-K Section 3.2(m) Cal Dive Contract Regulation S-K
    Title to Properties
  Section 3.2(n)
 A-22




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##### Table of Contents



10-Q, Section 3.2(n)
    Insurance. Section 3.2(o)
  Reorganization under the Code. Sections 6.2(c) 6.3(c)
  Opinion of Financial
    Advisors.
  Board and Stockholder Approval.
  Brokers Fees.
  Vessel Related Matters.
  Section 3.2(t)(i)(A)(I)
    and/or
     A-23




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##### Table of Contents



and/or
      Certain Business Practices.
  Ownership of Company Capital
    Stock.
  Funds.
  ARTICLE IV
  COVENANTS
    RELATING TO CONDUCT OF BUSINESS
  Covenants of the
    Company. Section 4.1
  Ordinary Course
    Company Capital
    Budget
 A-24




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##### Table of Contents



Dividends; Changes in Share
    Capital.
  Issuance of Securities. Section 4.1(f)
  Governing Documents.
  No Acquisitions.
  No Dispositions.
  Investments; Indebtedness. Section 4.1(e)
  Tax-Free Qualification.
 A-25




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##### Table of Contents



Sections 6.2(c) 6.3(c) Section 4.1
  Certain Actions. Sections 5.4 7.1
  Related Actions.
  Covenants of Cal Dive
  Section 4.2
  Ordinary Course.
  Dividends; Changes in Share
    Capital
  Issuance of
    Securities Section 4.2(a)(vi)
  Governing Documents
  No Acquisitions.
 A-26




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##### Table of Contents



No Dispositions
  Investments;
    Indebtedness Section
    4.2(a)(iv)
  Tax-Free
    Qualification Sections 6.2(c) 6.3(c) Section 4.2) Section 6.2(c)
  Certain Actions Section 7.1
  Related Actions.
    Governmental
    Filings.
 A-27




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##### Table of Contents



No Control of Other Partys
    Business.
  ARTICLE V
  ADDITIONAL
    AGREEMENTS
  Preparation of Information Statement/Proxy
    Statement/Prospectus; Stockholders Meeting.
  Form S-4. Form S-4 Form S-4 Form S-4 Form S-4 Form S-4 Form S-4 Form S-4 Form S-4 Form S-4 Form S-4 Form S-4. Form S-4
 A-28




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##### Table of Contents



S-4
  Form S-4 Statement/Proxy
  S-4 S-4.
  S-4 S-4.
  Form S-4 Section 3.1(s) Company
    Board Recommendation Section 5.4 Change in the Company Board
    Recommendation
  Access to Information.
 A-29




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##### Table of Contents



Required Actions.
  and/or Required Approvals
  Section 5.3(a)
  Sections 5.3(a) 5.3(b)
 A-30




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##### Table of Contents



Section 6.1(a) Section 5.3(a) Section 5.3(c)
    Acquisition Proposals.
  Company
    Representatives Section 5.4 Section 7.1(h)
  Section 5.4 Article VII
 A-31




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##### Table of Contents



Section 5.4 Section 5.4 Section 5.4(a) Section 5.4(c) Section 5.4(d)
  Section 5.4(d) Section 5.4(e) Section 5.4 Section 7.1(h) Section 7.2(b)(i) and/or
  Rules 14d-9 14e-2(a)
 A-32




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##### Table of Contents



Section 7.1(h) Section 7.2(b)(i)
  Fees and Expenses. Section 7.2 Form S-4
  Directors and Officers
    Indemnification and Insurance.
    Section 5.6 Section 5.6 Section 5.6 Section 5.6
  Employee Benefits; Retention Plan.
  New
    Plans Old
 A-33




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##### Table of Contents



Plans and/or
    Public Announcements.
  Listing of Shares of Cal Dive Common
    Stock.
  Affiliates. Exhibit A Affiliate Agreement
  Section 16
    Matters. Article I Article II Rule 16b-3
  Tax Matters. Section 6.2(c) Section 6.3(c) Regulation Section 1.368-2(g).
 A-34




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##### Table of Contents



Vessel Matters.
  ARTICLE VI
  CONDITIONS
    PRECEDENT
  Conditions to Each Partys Obligation to
    Effect the Merger.
  No Injunctions or Restraints;
    Illegality.
  HSR Act; Other
    Approvals.
  NYSE Listing.
  Effectiveness of the
    Form S-4. Form S-4 Form S-4
  Stockholder Approval.
  Additional Conditions to Obligations of
    Cal Dive.
  Representations and Warranties. Section 6.2(a)
  Performance of Obligations of the
    Company.
  Tax Opinion.
 A-35




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##### Table of Contents



Section 5.12
  Additional Conditions to Obligations of the
    Company.
  Representations and Warranties. Section 6.3(a)
  Performance of Obligations of
    Cal Dive.
  Tax Opinion. Section 5.12
  ARTICLE VII
  TERMINATION
  Termination.
    Section 7.1(b) Section 5.3)
  Sections 6.1(b) 6.1(c) 6.1(d)
 A-36




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##### Table of Contents



Section 7.1(c) Section 5.3
    Section 5.1, Section 7.1(h) Section 5.4
  Section 6.2(a) 6.2(b)
  Section 6.3(a) 6.3(b)
  Section 5.4(d)
  Effect of Termination.
  Section 7.1 Section 5.2 Section 5.5 Section 7.2 Article IX Section 7.2(b)(i) (ii) (iii)
  Section 7.1(h) Section 7.2(b)(i)
  Section 7.1(e) Section 7.2(b)(i)
  Section 7.1(d)
 A-37




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##### Table of Contents



Section 7.1(f) Section 7.1(f) Section 7.2(b)(iii)(A) Section 7.1(b)(iii)
  Section 7.2 Section
    7.2 Section 7.2 Section 5.5 Section 7.2
  ARTICLE VIII
  CERTAIN
    DEFINITIONS
    Acceptable Confidentiality Agreement Section 5.4
  Acquisition Proposal
  Affiliate
  Affiliate Agreement Section 5.10
  Agreement
  Antitrust Laws
 A-38




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##### Table of Contents



Beneficial ownership beneficially
    own
  Benefit Plan
  Business Day
  Cal Dive
  Cal Dive Benefit Plan
  Cal Dive Capital Stock
  Cal Dive Common Stock
  Cal Dive Contract Section 3.2(m)(i)
  Cal Dive Current
    10-Q Form 10-Q
  Cal Dive Disclosure Schedule
  Cal Dive ERISA Affiliate
  Cal Dive Necessary Consents Section 3.2(d)
  Cal Dive Preferred Stock
  Cal Dive SEC Documents Section 3.2(e)(i)
  Cal Dive Stock Plans
  Cal Dive Vessel Section 3.2(t)(i)(A)(I)
  CERCLA
  Certificate Section 2.1(c)
  Certificate of Merger Section 1.2
  Change in the Company Board Recommendation Section 5.1(f)
  Classification Society
  Closing Section 1.4
 A-39




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##### Table of Contents



Closing Date Section 1.4
  Code
  Company
  Company Benefit Plan
  Company Board Recommendation Section 5.1(f)
  Company Capital Budget Section 4.1(a)(ii)
  Company Capital Stock
  Company Common Stock
  Company Contract Section 3.1(m)(i)
  Company Current
    10-Q Form 10-Q
  Company Disclosure Schedule
  Company Employees
  Company ERISA Affiliate
  Company Necessary Consents Section 3.1(d)
  Company Preferred Stock
  Company Representatives Section 5.4(a)
  Company SEC Documents Section 3.1(e)(i)
  Company Stock Option Section 2.3(a)
  Company Stock Plans
  Company Stockholder Approval Section 3.1(c)(i)
  Company Stockholders Meeting Section 3.1(c)(i)
  Company Vessel Section 3.1(v)(i) Gulf Horizon
  Confidentiality Agreement
  Converted Cal Dive Option Section 2.3(a)
  Country of Registry
 A-40




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##### Table of Contents



DGCL
  DLLCA
  Dissenting Share Section 2.2
  DOJ
  Effective Time Section 1.2
  Environmental Claims clean-up, and/or
  Environmental Laws et seq et seq. et seq et
    seq. et seq. et seq. et
    seq. et
    seq. et seq. et
    seq.
  Environmental Permits
  ERISA
  Event of Loss
  Exception Shares and/or
  Exchange Act
  Exchange Agent Section 2.4(a)
 A-41




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##### Table of Contents



Exchange Fund Section 2.4(a)
  Exchange Ratio Section 2.1(a)
  Excluded Party
  Excluded Party Superior Proposal
  Expenses Form S-4
  Form S-4 Section 3.1(d)
  FTC
  GAAP
  Governmental Entity
  Hazardous Materials
  Helix
  HSR Act Hart-Scott-Rodino
  Indebtedness
  Information Statement/Proxy Statement/Prospectus Section 3.1(d)
  Knowledge Known
  Liens
  Mailing Date Section 2.4(b)
  Market Price
 A-42




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##### Table of Contents



Material Adverse Effect
  Merger Consideration Section 2.1(a)
  Merger
  Merger Sub
  Multiemployer Plan
  Nasdaq Global Market
  New Plans Section 5.7
  No-Shop Period Start Date
  NYSE
  Old Plans Section 5.7
  Other Party
  Party
  Pension Plan
  Per Share Cash Amount Section 2.1(a)
  Permitted Liens
  Person
 A-43




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##### Table of Contents



Plan of Merger
  Qualifying Amendment Form S-4
  Regulatory Law
  Release
  Required Approvals Section 5.3(a)
  Sarbanes-Oxley Act
  SEC
  Securities Act
  Stock Award Exchange Ratio
  Subsidiary
  Superior Proposal
  Surviving Company
  Tax Return
  Taxes
 A-44




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##### Table of Contents



Termination Date
  Termination Fee
  Vessel(s) Section 3.1(v)(i) Gulf Horizon Section 3.2(t)(i)(A)(I)
  Voting Debt
  ARTICLE IX
  GENERAL
    PROVISIONS
  Non-Survival of Representations, Warranties and
    Agreements. Article IX Section 5.6
  Notices.
    (281) 848-6502
    (713) 651-5246
    (713) 361-2693
 A-45




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##### Table of Contents



504-582-8012
  Interpretation.
      Counterparts.
  Entire Agreement; No Third Party
    Beneficiaries.
    Section 5.6
  Governing Law.
  Severability.
 A-46




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##### Table of Contents



Assignment.
  Submission to Jurisdiction;
    Waivers.
  Enforcement.
  Amendment.
  Extension; Waiver.
 A-47




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##### Table of Contents



IN WITNESS WHEREOF,
  CAL DIVE INTERNATIONAL, INC.
  By: /s/  Quinn
    J. Hebert     CAL DIVE ACQUISITION, LLC
  By:
    /s/  Quinn
    J. Hebert     HORIZON OFFSHORE, INC.
  By: /s/  David
    W. Sharp      Signature
    Page to Agreement and Plan of Merger
 A-48




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##### Table of Contents



Exhibit A
  FORM OF
    AFFILIATE AGREEMENT
  ,
    2007
    Company Rules and
    Regulations Commission Securities
    Act Merger Agreement Cal Dive Merger Sub Cal Dive
    Common Stock Merger
        Form S-4.
       A-49




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##### Table of Contents



Exchange Act
    By:     A-50




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##### Table of Contents



CAL DIVE INTERNATIONAL, INC.
  By:     CAL DIVE ACQUISITION, LLC
  By:     HORIZON OFFSHORE, INC.
  By:    A-51




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##### Table of Contents



ANNEX B  Opinion
    of Lehman Brothers Inc. dated June 11, 2007
  
  June 11,
    2007
  Board of
    Directors
    Horizon Offshore, Inc.
    2500 City West Blvd.
    Suite 2200
         Forms 10-K Forms 10-Q
 B-1




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##### Table of Contents



B-2




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##### Table of Contents



ANNEX C  Opinion
    of Banc of America Securities LLC dated June 11,
    2007
  BANC OF AMERICA SECURITIES
  Banc of America Securities LLC
    9 West
    57th
    Street
    New York, NY 10019
   Tel 888.583.8900
 June 11, 2007
  Board of Directors
 Cal Dive International, Inc.
 400 N. Sam Houston Parkway E., Suite 400
 Houston, Texas 77060
                       C-1




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##### Table of Contents



C-2




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##### Table of Contents



and/or
             C-3




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##### Table of Contents



ANNEX D  Section 262
    of the Delaware General Corporation Law
  §262
    APPRAISAL RIGHTS.
                   D-1




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##### Table of Contents



D-2




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##### Table of Contents



D-3




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##### Table of Contents



D-4




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##### Table of Contents



PART II
  INFORMATION
    NOT REQUIRED IN PROSPECTUS
    ITEM 20.
    Indemnification
    of Directors and Officers           II-1




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##### Table of Contents



ITEM 21.
    Exhibits
    and Financial Statement Schedules.  Exhibits.
  2
.1

Agreement and Plan of Merger,
    dated as of June 11, 2007, by and among Cal Dive
    International, Inc., Cal Dive Acquisition, LLC and Horizon
    Offshore, Inc., incorporated by reference to Exhibit 2.1 to
    the Current Report on
    Form 8-K,
    filed by the registrant with the Securities and Exchange
    Commission on June 12, 2007.3
.1

Amended and Restated Certificate
    of Incorporation of Cal Dive International, Inc., incorporated
    by reference to Exhibit 3.1 to the Annual Report on
    Form 10-K
    for the fiscal year ended December 31, 2006, filed by
    registrant with the Securities and Exchange Commission on
    March 1, 2007.3
.2

Amended and Restated Bylaws of Cal
    Dive International, Inc., incorporated by reference to
    Exhibit 3.2 to the Annual Report on
    Form 10-K
    for the fiscal year ended December 31, 2006, filed by the
    registrant with the Securities and Exchange Commission on
    March 1, 2007.4
.1

Specimen Common Stock certificate
    of Cal Dive International, Inc., incorporated by reference to
    Exhibit 4.1 to the Registration Statement on
    Form S-1
    (File
    No. 333-134609),
    initially filed by the registrant with the Securities and
    Exchange Commission on May 31, 2006, as amended.**5
.1

Opinion of Fulbright &
    Jaworski L.L.P., counsel to the registrant, regarding the
    legality of the common stock to be offered hereby.**8
.1

Opinion of Fulbright &
    Jaworski L.L.P. regarding tax matters.**8
.2

Opinion of Jones, Walker,
    Waechter, Poitevent, Carrère & Denègre,
    L.L.P. regarding tax matters.10
.1

Master Agreement between Cal Dive
    International, Inc. and Helix Energy Solutions Group, Inc.,
    incorporated by reference to Exhibit 10.1 to the Annual
    Report on
    Form 10-K
    for the fiscal year ended December 31, 2006, filed by
    registrant with the Securities and Exchange Commission on
    March 1, 2007.10
.2

Corporate Services Agreement
    between Cal Dive International, Inc. and Helix Energy Solutions
    Group, Inc., incorporated by reference to Exhibit 10.2 to
    the Annual Report on
    Form 10-K
    for the fiscal year ended December 31, 2006, filed by
    registrant with the Securities and Exchange Commission on
    March 1, 2007.10
.3

Registration Rights Agreement
    between Cal Dive International, Inc. and Helix Energy Solutions
    Group, Inc., incorporated by reference to Exhibit 10.3 to
    the Annual Report on
    Form 10-K
    for the fiscal year ended December 31, 2006, filed by
    registrant with the Securities and Exchange Commission on
    March 1, 2007.10
.4

Tax Matters Agreement between Cal
    Dive International, Inc. and Helix Energy Solutions Group, Inc.,
    incorporated by reference to Exhibit 10.4 to the Annual
    Report on
    Form 10-K
    for the fiscal year ended December 31, 2006, filed by
    registrant with the Securities and Exchange Commission on
    March 1, 2007.10
.5

Employee Matters Agreement between
    Cal Dive International, Inc. and Helix Energy Solutions Group,
    Inc., incorporated by reference to Exhibit 10.5 to the
    Annual Report on
    Form 10-K
    for the fiscal year ended December 31, 2006, filed by
    registrant with the Securities and Exchange Commission on
    March 1, 2007.10
.6ˆ

Cal Dive International, Inc.
    Amended and Restated 2006 Long Term Incentive Plan, incorporated
    by reference to Exhibit 10.1 to the Current Report on
    Form 8-K,
    filed by registrant with the Securities and Exchange Commission
    on May 11, 2007. II-2




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##### Table of Contents



10
.7ˆ

Form of Restricted Stock Agreement
    for 2006 Grants to Quinn J. Hébert, Scott T. Naughton, G.
    Kregg Lunsford, and Lisa M. Buchanan, incorporated by reference
    to Exhibit 10.7 to the Annual Report on
    Form 10-K
    for the fiscal year ended December 31, 2006, filed by
    registrant with the Securities and Exchange Commission on
    March 1, 2007.10
.8ˆ

Employment Agreement dated
    November 1, 2005, between Cal Dive International, Inc.
    (predecessor to Helix Energy Solutions Group, Inc.) and Quinn J.
    Hébert, incorporated by reference to Exhibit 10.8 to
    the Registration Statement on
    Form S-1
    (File
    No. 333-134609),
    initially filed by the registrant with the Securities and
    Exchange Commission on May 31, 2006, as amended.10
.9ˆ

Amended and Restated Employment
    Agreement dated February 15, 1999, between Cal Dive
    International, Inc. (predecessor to Helix Energy Solutions
    Group, Inc.) and Scott T. Naughton, incorporated by reference to
    Exhibit 10.9 to the Registration Statement on
    Form S-1
    (File
    No. 333-134609),
    initially filed by the registrant with the Securities and
    Exchange Commission on May 31, 2006, as amended.10
.10ˆ

Employment Agreement dated
    February 1, 2003, between Cal Dive International, Inc.
    (predecessor to Helix Energy Solutions Group, Inc.) and G. Kregg
    Lunsford, incorporated by reference to Exhibit 10.10 to the
    Registration Statement on
    Form S-1
    (File
    No. 333-134609),
    initially filed by the registrant with the Securities and
    Exchange Commission on May 31, 2006, as amended.10
.11

Credit Agreement dated
    November 20, 2006, among CDI Vessel Holdings LLC, Cal Dive
    International, Inc., Bank of America, N.A., as Administrative
    Agent, Amegy Bank National Association, as Documentation Agent,
    Banc of America Securities LLC and J.P. Morgan Securities,
    Inc., as Joint Lead Arrangers and Joint Book Runners, and the
    lenders from time to time party thereto, incorporated by
    reference to Exhibit 10.11 to the Registration Statement on
    Form S-1
    (File
    No. 333-134609),
    initially filed by the registrant with the Securities and
    Exchange Commission on May 31, 2006, as amended.10
.12

Amendment No. 1 to Credit
    Agreement dated as of December 15, 2006, by and among CDI
    Vessel Holdings LLC, Cal Dive International, Inc. and Bank of
    America, N.A., as Administrative Agent, and the lenders from
    time to time party thereto, incorporated by reference to
    Exhibit 10.12 to the Annual Report on
    Form 10-K
    for the fiscal year ended December 31, 2006, filed by
    registrant with the Securities and Exchange Commission on
    March 1, 2007.10
.13ˆ

Summary of 2007 Executive Officer
    Cash Compensation, incorporated by reference to
    Exhibit 10.13 to the Annual Report on
    Form 10-K
    for the fiscal year ended December 31, 2006, filed by
    registrant with the Securities and Exchange Commission on
    March 1, 2007.10
.14

Post-Closing Employee Matters
    Agreement dated February 1, 2007, between Cal Dive
    International, Inc. and Helix Energy Solutions Group, Inc.,
    incorporated by reference to Exhibit 10.1 to the Quarterly
    Report on
    Form 10-Q
    for the fiscal quarter ended March 31, 2007, filed by
    registrant with the Securities and Exchange Commission on
    May 4, 2007.10
.15

Form of Indemnity Agreement by and
    between Cal Dive International, Inc. and each of its directors
    and named executive officers, incorporated by reference to
    Exhibit 10.2 to the Current Report on
    Form 8-K,
    filed by registrant with the Securities and Exchange Commission
    on May 11, 2007.*21
.1

Subsidiaries of Cal Dive
    International, Inc.*23
.1

Consent of Ernst & Young
    LLP.*23
.2

Consent of Grant Thornton LLP.**23
.3

Consent of Fulbright &
    Jaworski L.L.P. (included in Exhibit 5.1).**23
.4

Consent of Fulbright &
    Jaworski L.L.P. (included in Exhibit 8.1).**23
.5

Consent of Jones, Walker,
    Waechter, Poitevent, Carrère & Denègre,
    L.L.P. (included in Exhibit 8.2).*23
.6

Consent of Spears &
    Associates, Inc.*24
.1

Powers of Attorney (included on
    the signature pages).*99
.1

Form of Proxy of Horizon Offshore,
    Inc.*99
.2

Consent of Prospective Director
    for David W. Sharp.*99
.3

Consent of Prospective Director
    for John T. Mills.    ˆ



Management contract or
    compensatory plan or arrangement. II-3




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##### Table of Contents



*



Filed herewith.**



To be filed by amendment.   Financial Statement Schedules.
    ITEM 22.
    Undertakings.             II-4




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##### Table of Contents



SIGNATURES
  Form S-4
  CAL DIVE INTERNATIONAL, INC.
  By:
    /s/  G.
    Kregg Lunsford      POWER OF
    ATTORNEY
    Form S-4
  Signature

Title/s/  Todd
    A. DittmannTodd
    A. Dittmann

Director/s/  David
    E. PrengDavid
    E. Preng

Director/s/  William
    L. TransierWilliam
    L. Transier

Director/s/  Owen
    KratzOwen
    Kratz

Director II-5




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Signature

Title/s/  Martin
    R. FerronMartin
    R. Ferron

Director/s/  Quinn
    J. HébertQuinn
    J. Hébert

President, Chief Executive Officer
    and Director
    (Principal Executive Officer)/s/  G.
    Kregg LunsfordG.
    Kregg Lunsford

Executive Vice President, Chief
    Financial Officer and Treasurer
    (Principal Financial and Accounting Officer)  II-6




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##### Table of Contents



EXHIBIT INDEX
  2
.1

Agreement and Plan of Merger,
    dated as of June 11, 2007, by and among Cal Dive
    International, Inc., Cal Dive Acquisition, LLC and Horizon
    Offshore, Inc., incorporated by reference to Exhibit 2.1 to
    the Current Report on
    Form 8-K,
    filed by the registrant with the Securities and Exchange
    Commission on June 12, 2007.3
.1

Amended and Restated Certificate
    of Incorporation of Cal Dive International, Inc., incorporated
    by reference to Exhibit 3.1 to the Annual Report on
    Form 10-K
    for the fiscal year ended December 31, 2006, filed by
    registrant with the Securities and Exchange Commission on
    March 1, 2007.3
.2

Amended and Restated Bylaws of Cal
    Dive International, Inc., incorporated by reference to
    Exhibit 3.2 to the Annual Report on
    Form 10-K
    for the fiscal year ended December 31, 2006, filed by the
    registrant with the Securities and Exchange Commission on
    March 1, 2007.4
.1

Specimen Common Stock certificate
    of Cal Dive International, Inc., incorporated by reference to
    Exhibit 4.1 to the Registration Statement on
    Form S-1
    (File
    No. 333-134609),
    initially filed by the registrant with the Securities and
    Exchange Commission on May 31, 2006, as amended.**5
.1

Opinion of Fulbright &
    Jaworski L.L.P., counsel to the registrant, regarding the
    legality of the common stock to be offered hereby.**8
.1

Opinion of Fulbright &
    Jaworski L.L.P. regarding tax matters.**8
.2

Opinion of Jones, Walker,
    Waechter, Poitevent, Carrère & Denègre,
    L.L.P. regarding tax matters.10
.1

Master Agreement between Cal Dive
    International, Inc. and Helix Energy Solutions Group, Inc.,
    incorporated by reference to Exhibit 10.1 to the Annual
    Report on
    Form 10-K
    for the fiscal year ended December 31, 2006, filed by
    registrant with the Securities and Exchange Commission on
    March 1, 2007.10
.2

Corporate Services Agreement
    between Cal Dive International, Inc. and Helix Energy Solutions
    Group, Inc., incorporated by reference to Exhibit 10.2 to
    the Annual Report on
    Form 10-K
    for the fiscal year ended December 31, 2006, filed by
    registrant with the Securities and Exchange Commission on
    March 1, 2007.10
.3

Registration Rights Agreement
    between Cal Dive International, Inc. and Helix Energy Solutions
    Group, Inc., incorporated by reference to Exhibit 10.3 to
    the Annual Report on
    Form 10-K
    for the fiscal year ended December 31, 2006, filed by
    registrant with the Securities and Exchange Commission on
    March 1, 2007.10
.4

Tax Matters Agreement between Cal
    Dive International, Inc. and Helix Energy Solutions Group, Inc.,
    incorporated by reference to Exhibit 10.4 to the Annual
    Report on
    Form 10-K
    for the fiscal year ended December 31, 2006, filed by
    registrant with the Securities and Exchange Commission on
    March 1, 2007.10
.5

Employee Matters Agreement between
    Cal Dive International, Inc. and Helix Energy Solutions Group,
    Inc., incorporated by reference to Exhibit 10.5 to the
    Annual Report on
    Form 10-K
    for the fiscal year ended December 31, 2006, filed by
    registrant with the Securities and Exchange Commission on
    March 1, 2007.10
.6ˆ

Cal Dive International, Inc.
    Amended and Restated 2006 Long Term Incentive Plan, incorporated
    by reference to Exhibit 10.1 to the Current Report on
    Form 8-K,
    filed by registrant with the Securities and Exchange Commission
    on May 11, 2007.10
.7ˆ

Form of Restricted Stock Agreement
    for 2006 Grants to Quinn J. Hébert, Scott T. Naughton,
    G. Kregg Lunsford, and Lisa M. Buchanan, incorporated by
    reference to Exhibit 10.7 to the Annual Report on
    Form 10-K
    for the fiscal year ended December 31, 2006, filed by
    registrant with the Securities and Exchange Commission on
    March 1, 2007.10
.8ˆ

Employment Agreement dated
    November 1, 2005, between Cal Dive International, Inc.
    (predecessor to Helix Energy Solutions Group, Inc.) and Quinn J.
    Hébert, incorporated by reference to Exhibit 10.8 to
    the Registration Statement on
    Form S-1
    (File
    No. 333-134609),
    initially filed by the registrant with the Securities and
    Exchange Commission on May 31, 2006, as amended.




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##### Table of Contents



10
.9ˆ

Amended and Restated Employment
    Agreement dated February 15, 1999, between Cal Dive
    International, Inc. (predecessor to Helix Energy Solutions
    Group, Inc.) and Scott T. Naughton, incorporated by reference to
    Exhibit 10.9 to the Registration Statement on
    Form S-1
    (File
    No. 333-134609),
    initially filed by the registrant with the Securities and
    Exchange Commission on May 31, 2006, as amended.10
.10ˆ

Employment Agreement dated
    February 1, 2003, between Cal Dive International, Inc.
    (predecessor to Helix Energy Solutions Group, Inc.) and G. Kregg
    Lunsford, incorporated by reference to Exhibit 10.10 to the
    Registration Statement on
    Form S-1
    (File
    No. 333-134609),
    initially filed by the registrant with the Securities and
    Exchange Commission on May 31, 2006, as amended.10
.11

Credit Agreement dated
    November 20, 2006, among CDI Vessel Holdings LLC, Cal Dive
    International, Inc., Bank of America, N.A., as Administrative
    Agent, Amegy Bank National Association, as Documentation Agent,
    Banc of America Securities LLC and J.P. Morgan Securities,
    Inc., as Joint Lead Arrangers and Joint Book Runners, and the
    lenders from time to time party thereto, incorporated by
    reference to Exhibit 10.11 to the Registration Statement on
    Form S-1
    (File
    No. 333-134609),
    initially filed by the registrant with the Securities and
    Exchange Commission on May 31, 2006, as amended.10
.12

Amendment No. 1 to Credit
    Agreement dated as of December 15, 2006, by and among CDI
    Vessel Holdings LLC, Cal Dive International, Inc. and Bank of
    America, N.A., as Administrative Agent, and the lenders from
    time to time party thereto, incorporated by reference to
    Exhibit 10.12 to the Annual Report on
    Form 10-K
    for the fiscal year ended December 31, 2006, filed by
    registrant with the Securities and Exchange Commission on
    March 1, 2007.10
.13ˆ

Summary of 2007 Executive Officer
    Cash Compensation, incorporated by reference to
    Exhibit 10.13 to the Annual Report on
    Form 10-K
    for the fiscal year ended December 31, 2006, filed by
    registrant with the Securities and Exchange Commission on
    March 1, 2007.10
.14

Post-Closing Employee Matters
    Agreement dated February 1, 2007, between Cal Dive
    International, Inc. and Helix Energy Solutions Group, Inc.,
    incorporated by reference to Exhibit 10.1 to the Quarterly
    Report on
    Form 10-Q
    for the fiscal quarter ended March 31, 2007, filed by
    registrant with the Securities and Exchange Commission on
    May 4, 2007.10
.15

Form of Indemnity Agreement by and
    between Cal Dive International, Inc. and each of its directors
    and named executive officers, incorporated by reference to
    Exhibit 10.2 to the Current Report on
    Form 8-K,
    filed by registrant with the Securities and Exchange Commission
    on May 11, 2007.*21
.1

Subsidiaries of Cal Dive
    International, Inc.*23
.1

Consent of Ernst & Young
    LLP.*23
.2

Consent of Grant Thornton LLP.**23
.3

Consent of Fulbright &
    Jaworski L.L.P. (included in Exhibit 5.1).**23
.4

Consent of Fulbright &
    Jaworski L.L.P. (included in Exhibit 8.1).**23
.5

Consent of Jones, Walker,
    Waechter, Poitevent, Carrère & Denègre,
    L.L.P. (included in Exhibit 8.2).*23
.6

Consent of Spears &
    Associates, Inc.*24
.1

Powers of Attorney (included on
    the signature pages).*99
.1

Form of Proxy of Horizon Offshore,
    Inc.*99
.2

Consent of Prospective Director
    for David W. Sharp.*99
.3

Consent of Prospective Director
    for John T. Mills.     ˆ



Management contract or
    compensatory plan or arrangement.*



Filed herewith.**



To be filed by amendment.