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                                                                   Exhibit 99.10

                      Form of Subscription Agency Agreement

                  This Subscription Agent Agreement (the "Agreement") is made as
         of the ___ day of __________, 2002, by and between Harken Energy
         Corporation, a Delaware corporation (the "Company"), and American Stock
         Transfer & Trust Company, as subscription agent (the "Agent").

                                    RECITALS

                  WHEREAS, the Company has caused a prospectus (the
         "Prospectus") included in the Registration Statement on Form S-3, File
         No. 333-_______, to be filed with the Securities and Exchange
         Commission (the "Commission") on September ___, 2002, as amended by any
         amendment filed with respect thereto (collectively the "Registration
         Statement"), which relates to a proposed distribution by the Company of
         non-transferable subscription rights (the "Subscription Rights") to
         purchase shares of the Company's common stock, par value $0.01 per
         share ("Common Stock"), upon the exercise of such Subscription Rights
         (the distribution of the Subscription Rights and the sale of shares of
         Common Stock upon the exercise thereof as contemplated by the
         Registration Statement is referred to herein as the "Rights Offering");

                  WHEREAS, the Subscription Rights will be distributed on or
         about ___, 2002, to holders ("Holders") of record of shares of Common
         Stock, the Company's Series G1 Convertible Preferred Stock ("Series G1
         Preferred Stock"), and the Company's Series G-2 Convertible Preferred
         Stock ("Series G1 Preferred Stock") as of the close of business on ___,
         2002 (the "Record Date"), at a rate of one Subscription Right for each
         share of Common Stock (or in the case of the Series G1 Preferred Stock
         and Series G2 Preferred Stock, one Subscription Right for each share of
         Common stock issuable upon conversion) held on the Record Date;

                  WHEREAS, the Company has authorized the issuance of an
         aggregate number of authorized and unissued shares of Common Stock (the
         "Underlying Shares") equal to the aggregate number of Subscription
         Rights to be distributed pursuant to the Rights Offering;

                  WHEREAS, Holders will be entitled to subscribe to purchase at
         a per share price of $0.__ (the "Subscription Price") one Underlying
         Share for each Subscription Right held (the "Subscription Privilege"),
         which right to subscribe for such Underlying Shares pursuant to the
         Subscription Privilege is not transferable; and

                  WHEREAS, the Company wishes the Agent to perform certain acts
         on behalf of the Company, and the Agent is willing to so act, in
         connection with the Rights Offering as set forth herein, all upon the
         terms and conditions set forth herein.

                  NOW, THEREFORE, in consideration of the foregoing and of the
         mutual agreements set forth herein, the parties agree as follows:

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                                    ARTICLE 1
                              APPOINTMENT OF AGENT

               Section 1.1. Appointment of Agent. The Company hereby appoints
         the Agent to act as agent for the Company in accordance with the
         instructions set forth in this Agreement. The Agent hereby accepts such
         appointment.

                                    ARTICLE 2
                             ISSUANCE OF SECURITIES

               Section 2.1. Authorization; Issuance. The Company has authorized
         the issuance of the Subscription Rights and, following the Record Date
         and the effectiveness of the Registration Statement, will issue such
         Subscription Rights to the Holders as contemplated by the Registration
         Statement. The Company will notify the Agent upon the effectiveness of
         the Registration Statement. As transfer agent and registrar for the
         shares of Common Stock, the Agent shall provide such assistance as the
         Company may require in order to effect the distribution of the
         Subscription Rights to Holders, including assistance in determining the
         number of Subscription Rights to be distributed to each such Holder and
         assistance in distributing the Subscription Documents (as defined in
         Section 5.2 hereof) evidencing the Subscription Rights and all other
         ancillary documents and issuance of the Underlying Shares.

               Section 2.2. Reservation. The Company has authorized the issuance
         of and will hold in reserve the Underlying Shares, and upon the valid
         exercise of Subscription Rights, the Company will issue Underlying
         Shares to validly exercising Holders as set forth in the Registration
         Statement.

                                    ARTICLE 3
                       SUBSCRIPTION RIGHTS AND ISSUANCE OF
                             SUBSCRIPTION DOCUMENTS

               Section 3.1. Subscription Rights and Issuance of Subscription
         Documents. Each set of Subscription Documents shall contain a
         Subscription Certificate which shall be non-transferable. The Agent
         shall, in its capacity as transfer agent and registrar of the Company,
         maintain a register of Subscription Certificates and the Holders
         thereof. Each Subscription Certificate shall, subject to the provisions
         thereof, entitle only the Holder in whose name it is recorded the right
         to subscribe for prior to 5:00 P.M., New York City time, on _____,  __,
         2002, (the "Expiration Date"), at the Subscription Price a number of
         shares equal to one Underlying Share for every share of Common Stock
         held by each Holder (or in the case of the Series G1 preferred stock
         and Series G2 Preferred Stock, one subscription right for each share of
         Common Stock issuable upon conversion of the Series G1 Preferred Stock
         and G2 Preferred Stock) on the Record Date (the "Subscription
         Privilege"). The Company shall certify to the Agent the number of
         shares of Common Stock into which the Series G1 Preferred Stock and
         Series G2 Preferred Stock is convertible as of the Record Date and the
         names, addresses, and other information of the Holders of such stock as
         the Agent may reasonably require in connection with the performance of
         its obligations under this Agreement.

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                                    ARTICLE 4
                    FRACTIONAL SUBSCRIPTION RIGHTS AND SHARES

               Section 4.1. Fractional Subscription Rights and Shares. The
         Company shall not issue fractions of Subscription Rights nor shall the
         Agent distribute Subscription Certificates which evidence fractional
         Subscription Rights. The number of Subscription Rights issued to each
         Holder will be rounded up to the nearest whole number. All questions as
         to the validity and eligibility of any rounding of fractional
         Subscription Rights shall be determined by the Company in its sole
         discretion, and its determination shall be final and binding. The
         Company shall not issue fractional shares of Common Stock to exercising
         Holders upon exercise of Subscription Rights.

                                    ARTICLE 5
                  FORM AND EXECUTION OF SUBSCRIPTION DOCUMENTS

               Section 5.1. Subscription Certificates. Each Subscription
         Certificate shall evidence the Subscription Rights of the Holder
         therein named to purchase Common Stock upon the terms and conditions
         set forth in the Subscription Documents.

               Section 5.2. Form; Execution. Upon the written advice of the
         Company, signed by any of its duly authorized officers, as to the
         Record Date, the Agent shall, from a list of the Company's stockholders
         as of the Record Date to be prepared by the Agent in its capacity as
         transfer agent of the Company, and from the list of Holders of the
         Series G1 Preferred Stock and Series G2 Preferred Stock delivered to
         the Agent pursuant to Section 3.1 above, prepare and record
         Subscription Certificates in the names of the Holders, setting forth
         the number of Subscription Rights to subscribe for the Company's Common
         Stock calculated on the basis of one Subscription Right for each share
         of Common Stock recorded on the books in the name of each such Holder,
         or in the case of the Series G1 Preferred Stock and Series G2 preferred
         Stock, one Subscription Right for each share of Common Stock issuable
         upon conversion, as certified to the Agent in Section 3.1 above. Each
         Subscription Certificate shall be dated as of the Record Date and shall
         be executed manually or by facsimile signature of a duly authorized
         officer of the Agent. Upon the written advice, signed as aforesaid, as
         to the effective date of the Registration Statement, the Agent shall
         promptly countersign and deliver the Subscription Certificate, together
         with a copy of the Prospectus, instruction letter and any other
         document as the Company deems necessary or appropriate (collectively
         the "Subscription Documents"), to all Holders. No Subscription
         Documents shall be valid for any purpose unless so executed. Delivery
         shall be by first class mail (without registration or insurance).

               Section 5.3. Foreign Addresses. The Agent will mail Subscription
         Documents to Holders whose addresses are outside the United States or
         who have an Army Post Office or Fleet Post Office address as provided
         in Section 5.2 above.

                                    ARTICLE 6
                EXERCISE OF SUBSCRIPTION RIGHTS; EXERCISE PRICE;
                                 EXPIRATION DATE

               Section 6.1. Exercise of Subscription Rights. Each Holder may
         exercise some or all of the Subscription Rights evidenced by the
         Subscription Certificate (but not in amounts of less than one
         Subscription Right or an integral multiple thereof) by delivering to
         the Agent, on or prior to the Expiration Date, properly completed and
         executed Subscription

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         Documents evidencing such Subscription Rights (with signatures
         guaranteed, if required by Section 6.9 hereof, by a financial
         institution (including commercial banks, savings and loan associations
         and brokerage houses) that is a member of a recognized signature
         guarantee or medallion program within the meaning of Rule 17Ad-15 under
         the Securities Exchange Act of 1934, as amended (each, an "Eligible
         Institution")), together with payment of the Subscription Price for
         each Underlying Share subscribed for pursuant to the Subscription
         Privilege. In the case or persons acquiring shares at an aggregate
         Subscription Price of $1,000,000 or more, an alternative payment method
         may be arranged with the Agent and approved by the Company.

               Section 6.2. Depositary Trust Company. In the case of Holders of
         Subscription Rights that are held of record through The Depository
         Trust Company ("DTC"), exercises of the Subscription Privilege may be
         effected by instructing DTC to transfer Subscription Rights from the
         DTC account of such Holder to the DTC account of the Agent, together
         with payment of the Subscription Price for each Underlying Share
         subscribed for pursuant to the Subscription Privilege. Alternatively, a
         Holder may exercise the Subscription Rights evidenced by the
         Subscription Certificate by effecting compliance with the procedures
         for guaranteed delivery set forth in Section 6.3 below.

               Section 6.3. Guaranteed Delivery Procedures. If a Holder wishes
         to exercise Subscription Rights, but time will not permit such Holder
         to cause the Subscription Certificate evidencing such Subscription
         Rights to reach the Agent on or prior to the Expiration Date, such
         Subscription Rights may nevertheless be exercised if all of the
         following conditions (the "Guaranteed Delivery Procedures") are met:
         (a) such Holder has caused payment in full of the Subscription Price
         for each Underlying Share being subscribed for pursuant to the
         Subscription Privilege to be received (in the manner set forth in
         Section 6.5 hereof) by the Agent on or prior to the Expiration Date;
         (b) the Agent receives, on or prior to the Expiration Date, a guarantee
         notice (a "Notice of Guaranteed Delivery"), substantially in the form
         provided with the Subscription Documents, from an Eligible Institution,
         stating the name of the exercising Holder, the number of Subscription
         Rights represented by the Subscription Certificate or Subscription
         Certificates held by such exercising Holder, the number of Underlying
         Shares being subscribed for pursuant to the Subscription Privilege, and
         guaranteeing the delivery to the Agent of the Subscription Certificate
         evidencing such Subscription Rights at or prior to 5:00 p.m., New York
         City time, on the date three American Stock Exchange ("AMEX") trading
         days following the date of the Notice of Guaranteed Delivery; and (c)
         the properly completed Subscription Certificate(s) evidencing the
         Subscription Rights being exercised, with any required signatures
         guaranteed, are received by the Agent, or such Subscription Rights are
         transferred into the DTC account of the Agent, at or prior to 5:00
         p.m., New York City time, on the date three AMEX trading days following
         the date of the Notice of Guaranteed Delivery relating thereto. The
         Notice of Guaranteed Delivery may be delivered to the Agent in the same
         manner as Subscription Certificates at the addresses set forth above,
         or may be transmitted to the Agent by telegram or facsimile
         transmission (facsimile: (718) 921-8336).

               Section 6.4. Expiration of Rights. The Subscription Rights shall
         expire at 5:00 p.m., New York City time, on the Expiration Date.

               Section 6.5. Deemed Exercises; Subscription Excess. If an
         exercising Holder has not indicated the number of Subscription Rights
         being exercised, or if the Subscription Price payment forwarded by such
         Holder to the Agent is not sufficient to purchase the number of shares
         subscribed for, the Holder will be deemed to have exercised the
         Subscription

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         Privilege with respect to the maximum number of whole Subscription
         Rights which may be exercised for the Subscription Price delivered to
         the Agent. To the extent the payment forwarded by the Holder exceeds
         maximum number of whole Subscription Rights which may be exercised for
         the Subscription Price ("Subscription Excess"), the Agent, as soon as
         practicable after the exercise of the Subscription Rights, shall mail
         to such Holders any portion of the Subscription Excess, without
         interest or deduction.

               Section 6.6. Bank Account. The Agent shall hold all proceeds of
         the Rights Offering in a segregated bank account (the "Bank Account").
         Upon receipt by the Agent of a written notice from the Company and
         following issuance of the Underlying Shares, the Agent shall and is
         hereby directed to withdraw from the Bank Account in which the proceeds
         of the Rights Offering have been held and pay to, credit to the account
         of or otherwise transfer to the Company all such Funds. At the request
         of the Company, any portion of the Underlying Shares shall be issued
         and the corresponding proceeds shall be remitted to the Company.

               Section 6.7. Acceptance of Certificates. The Agent is authorized
         to accept only Subscription Certificates (other than Subscription
         Certificates delivered in accordance with the procedure for guaranteed
         delivery set forth in Section 6.3, or transfers of Subscription Rights
         to its account at DTC), received prior to 5:00 p.m., New York City
         time, on the Expiration Date.

               Section 6.8. No Revocation. Once a Holder has exercised a
         Subscription Right, such exercise may not be revoked.

               Section 6.9. Guaranteed Signatures. If a Holder requests that the
         certificate representing the Common Stock to be issued in a name other
         than the name of the Holder or such certificate is to be sent to an
         address other than the address shown on such Holders Subscription
         Certificate, the signatures on such Subscription Certificate must be
         guaranteed by an Eligible Institution.

                                    ARTICLE 7
                            VALIDITY OF SUBSCRIPTIONS

               Section 7.1. Validity of Subscriptions. Irregular subscriptions
         and improperly executed Subscription Documents not otherwise covered by
         specific instructions herein shall be submitted to an appropriate
         officer of the Company and handled in accordance with his or her
         instructions. Such instructions will be documented by the Agent
         indicating the instructing officer and the date thereof.

                                    ARTICLE 8
                         DELIVERY OF STOCK CERTIFICATES

               Section 8.1. Delivery of Stock Certificates. As soon as
         practicable after the Expiration Date, the Agent shall deliver to such
         exercising Subscription Rights holder certificates representing the
         shares of Common Stock purchased pursuant to the Subscription
         Privilege.

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                                    ARTICLE 9
                                     REPORTS

               Section 9.1. Reports. The Agent shall notify both the Company and
         its designated representatives by telephone as requested during the
         period commencing with the mailing of Subscription Documents and ending
         on the Expiration Date (and in the case of guaranteed deliveries
         pursuant to Section 6.3 the period ending three AMEX trading days after
         the Expiration Date), which notice shall thereafter be confirmed in
         writing, of (i) the number of Subscription Rights exercised on the day
         of such request, (ii) the number of Underlying Shares subscribed for
         pursuant to the Subscription Privilege and the number of such
         Subscription Rights for which payment has been received, (iii) the
         number of Subscription Rights subject to guaranteed delivery pursuant
         to Section 6.3 on such day, (iv) the number of Subscription Rights for
         which defective exercises have been received on such day and (v)
         cumulative totals derived from the information set forth in clauses (i)
         through (iv) above. At or before 5:00 p.m., New York City time, on the
         first AMEX trading day following the Expiration Date, the Agent shall
         certify in writing to the Company the cumulative totals through the
         Expiration Date derived from the information set forth in clauses (i)
         through (iv) above. The Agent shall also maintain and update a listing
         of Holders who have fully or partially exercised their Subscription
         Rights and Holders who have not exercised their Subscription Rights.
         The Agent shall provide the Company or its designated representatives
         with the information compiled pursuant to this Article 10 as any of
         them shall request. The Agent hereby represents, warrants and agrees
         that the information contained in each notification referred to in this
         Article 9 shall be accurate in all material respects.

                                   ARTICLE 10
                               LOSS OR MUTILATION

               Section 10.1. Loss or Mutilation. Upon receipt by the Company and
         the Agent of evidence reasonably satisfactory to them of the loss,
         theft, destruction or mutilation of a Subscription Certificate, and, in
         case of loss, theft or destruction, of indemnity and/or security
         satisfactory to them, which may be in the form of an open penalty bond,
         and reimbursement to the Company and the Agent of all reasonable
         expenses incidental thereto, and upon surrender and cancellation of the
         Subscription Certificate if mutilated, the Company will make and
         deliver a new Subscription Certificate of like tenor to the Agent for
         delivery to the registered owner in lieu of the Subscription
         Certificate so lost, stolen, destroyed or mutilated. If required by the
         Company or the Agent an indemnity bond must be sufficient in the
         judgment of both to protect the Company, the Agent or any agent thereof
         from any loss which any of them may suffer if a Subscription
         Certificate is replaced.

                                   ARTICLE 11
                            COMPENSATION FOR SERVICES

               Section 11.1. Compensation. The Company agrees to pay to the
         Agent a fee in the amount of $________ as compensation for its services
         in acting as Agent, plus postage fees incurred in the performance of
         Agent's duties hereunder.

                                   ARTICLE 12
                        INSTRUCTIONS AND INDEMNIFICATION

               Section 12.1. Instructions; Indemnification. The Agent undertakes
         the duties and obligations imposed by this Agreement upon the following
         terms and conditions:

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               (a) The Agent shall be entitled to rely upon any written
         instructions or directions furnished to it by Mikel D. Faulkner, the
         Company's Chairman and Chief Executive Officer, Bruce N. Huff, the
         Company's President and Chief Operating Officer, and A. Wayne Hennecke,
         the Company's Senior Vice President - Finance and Secretary, or their
         designees (each, an "Authorizing Person"), whether in conformity with
         the provisions of this Agreement or constituting a modification hereof
         or a supplement hereto. Without limiting the generality of the
         foregoing or any other provision of this Agreement, the Agent, in
         connection with its duties hereunder, shall not be under any duty or
         obligation to inquire into the validity or invalidity or authority or
         lack thereof of any instruction or direction from an Authorizing Person
         of the Company which conforms to the applicable requirements of this
         Agreement and which the Agent reasonably believes to be genuine and
         shall not be liable for any delays, errors or loss of data occurring by
         reason of circumstances beyond the Agent's control.

               (b) The Company also agrees to indemnify and hold the Agent
         harmless against any losses, claims, actions, damages, liabilities,
         costs or expenses (including reasonable fees and disbursements of legal
         counsel) (collectively, "Claims") that the Agent may incur or become
         subject to, arising from or out of any claim or liability resulting
         from actions taken as Agent pursuant to this Agreement; provided,
         however, that such covenant and agreement does not extend to, and the
         Agent shall not be indemnified or held harmless with respect to, such
         Claims incurred or suffered by the Agent as a result, or arising out,
         of the Agent's negligence, misconduct, bad faith or breach of this
         Agreement. In connection therewith: (i) in no case shall the Company be
         liable with respect to any Claim against the Agent unless the Agent
         shall have notified the Company in writing of the assertion of a Claim
         against it promptly after the Agent shall have notice of a Claim or
         shall have been served with the summons or other legal process giving
         information as to the nature and basis of the Claim; provided, however,
         that the failure of the Agent to notify the Company in the above manner
         will absolve the Company of liability only when such failure will
         result or has resulted in prejudice to the Company with respect to such
         claim; (ii) the Company shall be entitled to control the defense of any
         suit brought to enforce any such Claim; and (iii) the Agent agrees not
         to settle or compromise any Claim with respect to which it may seek
         indemnification from the Company without the prior written consent of
         the Company. In no event shall the Company be liable for the fees and
         expenses of any additional counsel that the Agent may retain.

               (c) The Agent shall be protected and shall incur no liability for
         or in respect of any action taken, suffered or omitted by it without
         negligence and in good faith in connection with its administration of
         this Agreement in reliance upon any Subscription Certificate, or
         written power of attorney, endorsement, affidavit, letter, notice,
         direction, consent, certificate, statement or other paper or document
         reasonably believed by it to be genuine and to be signed, executed and,
         where necessary, verified or acknowledged by the proper person or
         person.

                                   ARTICLE 13
                     INTERPRETATION AND FUTURE INSTRUCTIONS

               Section 13.1. Interpretation. All questions as to the timeliness,
         validity, form and eligibility of any exercise of Subscription Rights
         will be determined by the Company whose

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         determinations shall be final and binding. The Company in its sole
         discretion may waive any defect or irregularity, permit a defect or
         irregularity to be corrected within such time as it may determine or
         reject the purported exercise of any Subscription Right. Subscriptions
         will not be deemed to have been received or accepted until all
         irregularities have been waived or cured within such time as the
         Company determines in its sole discretion. Neither the Company nor the
         Agent shall be under any duty to give notification of any defect or
         irregularity in connection with the submission of Subscription
         Documents or incur any liability for failure to give such notification.

               Section 13.2. Future Instructions. The Agent is hereby authorized
         and directed to accept written instructions with respect to the
         performance of its duties hereunder from an authorized officer of the
         Company, and to apply to such officers for written advice or
         instructions in connection with its duties, and it shall not be liable
         for any action taken or suffered to be taken by it in good faith in
         accordance with written instructions of any such officer.

                                   ARTICLE 14
                                PAYMENT OF TAXES

               Section 14.1. Payment of Taxes. The Company covenants and agrees
         that it will pay when due and payable all documentary, stamp and other
         taxes, if any, which may be payable in respect of the issuance or
         delivery of any Subscription Certificate or of the Underlying Shares;
         provided, however, that the Company shall not be liable for any tax
         liability arising out of any transaction which results in, or is deemed
         to be, an exchange of Subscription Rights or shares or a constructive
         dividend with respect to the Subscription Rights or shares, and
         provided further, that the Company shall not be required to pay any tax
         or other governmental charge which may be payable in respect of the
         issuance or delivery of certificates for shares of Common Stock in name
         other than that of the registered Holder of such Subscription
         Certificate evidencing the Subscription Rights exercised, and the Agent
         shall not issue any such certificate until such tax or governmental
         charge, if required, shall have been paid.

                                   ARTICLE 15
            CANCELLATION AND DESTRUCTION OF SUBSCRIPTION CERTIFICATES

               Section 15.1. Cancellation and Destruction. All Subscription
         Certificates surrendered for the purpose of exercise, exchange, or
         substitution shall be canceled by the Agent, and no Subscription
         Certificates shall be issued in lieu thereof except as expressly
         permitted by provisions of this Agreement. The Company shall deliver to
         the Agent for cancellation and retirement, and the Agent shall so
         cancel and return, any other Subscription Certificate purchased or
         acquired by the Company otherwise than upon the exercise thereof. The
         Agent shall deliver all canceled Subscription Certificates to the
         Company, or shall, at the written request of the Company, destroy such
         canceled Subscription Certificates, and in such case shall deliver a
         certificate of destruction thereof to the Company.

                                   ARTICLE 16
                       CHANGES IN SUBSCRIPTION CERTIFICATE

               Section 16.1. Changes in Subscription Certificate. The Agent may,
         without the consent or concurrence of the Holders in whose names
         Subscription Certificates are registered, by supplemental agreement or
         otherwise, concur with the Company in making any changes or

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         corrections in a Subscription Certificate that it shall have been
         advised by counsel (who may be counsel for the Company) is appropriate
         to cure any ambiguity or to correct any defective or inconsistent
         provision or clerical omission or mistake or manifest error therein or
         herein contained, and which shall not be inconsistent with the
         provision of the Subscription Certificate except insofar as any such
         change may confer additional rights upon the Holders.

                                   ARTICLE 17
                            ASSIGNMENT AND DELEGATION

               Section 17.1. No Assignment; Delegation. Neither this Agreement
         nor any rights or obligations hereunder may be assigned or delegated by
         either party without the prior written consent of the other party.

               Section 17.2. Binding Nature. This Agreement shall inure to the
         benefit of and be binding upon the parties and their respective
         permitted successors and assigns. Nothing in this Agreement is intended
         or shall be construed to confer upon any other person any right, remedy
         or claim or to impose upon any other person any duty, liability or
         obligation.

                                   ARTICLE 18
                    NOTICES TO THE COMPANY, HOLDERS AND AGENT

               Section 18.1. Notices. All notices and other communications
         provided for or permitted hereunder shall be made by hand delivery,
         prepaid certified first-class mail (return receipt requested), or
         telecopier (with written confirmation of receipt):

               (a)  if to the Company, to:

                    Harken Energy Corporation
                    580 WestLake Park Blvd., Suite 600
                    Houston, TX 77079
                    Attention: A. Wayne Hennecke, Vice President - Finance and
                               Secretary
                    Telephone: (281) 508-4040
                    Facsimile: (281) 504-4100

               (b)  if to the Agent, to:

                    American Stock Transfer & Trust Company
                    40 Wall Street, 46th Floor
                    New York, NY 10005
                    Attention: Exchange Department
                    Telephone: (718) 921-8200
                    Facsimile: (718) 234-5001

               (c)  if to a Holder,

               at the address shown on the registry books of the Company, or in
               the case of Holders of Series G1 Preferred Stock or Series G2
               Preferred Stock, at the address provided by the Company pursuant
               to the terms of this Agreement.

               All such notices and communications shall be deemed to have been
         duly given: when

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         delivered by hand, if personally delivered; when by certified mail, two
         business days after being deposited in the mail, postage prepaid, if
         mailed as aforesaid; and when receipt is acknowledged, if telecopied.

                                   ARTICLE 19
                            MISCELLANEOUS PROVISIONS

               Section 19.1. Governing Law. The validity, interpretation and
         performance of this Agreement shall be governed by the law of the state
         of Delaware, without regard to its principles of conflicts of law. The
         parties agree that with respect to all unresolved disputes arising out
         of this Agreement they shall submit to the jurisdiction of any state or
         federal court sitting in Houston Texas.

               Section 19.2. Severability. The parties hereto agree that if any
         of the provisions contained in this Agreement shall be determined
         invalid, unlawful or unenforceable to any extent, such provisions shall
         be deemed modified to the extent necessary to render such provisions
         enforceable. The parties hereto further agree that this Agreement shall
         be deemed severable, and the invalidity, unlawfulness or
         unenforceability of any term or provision thereof shall not affect the
         validity, legality or enforceability of this Agreement or of any term
         or provision hereof.

               Section 19.3. Counterparts. This Agreement may be executed in one
         or more counterparts, each of which shall be deemed an original and all
         of which together shall be considered one and the same agreement.

               Section 19.4. Captions. The captions and descriptive headings
         herein are for the convenience of the parties only. They do not in any
         way modify, amplify, alter or give full notice of the provisions
         hereof.

               Section 19.5. Facsimile Signatures. Any facsimile signature of
         any party hereto shall constitute a legal, valid and binding execution
         hereof by such party.

               Section 19.6. Further Actions. Each party agrees to perform such
         further acts and execute such further documents as are necessary to
         effect the purposes of this Agreement.

                         [SIGNATURES ON FOLLOWING PAGE]
                                      *****

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               IN WITNESS WHEREOF, the parties have hereunto set their hands, as
         of the day and year first above written.

                            HARKEN ENERGY CORPORATION


                            By: ________________________________
                                Name:
                                Title:


                            AMERICAN STOCK TRANSFER &
                            TRUST COMPANY


                            By: ________________________________
                                Name:
                                Title:

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