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                                                                    EXHIBIT 4.11


                          AMENDMENT TO RIGHTS AGREEMENT

         AMENDMENT TO RIGHTS AGREEMENT (this "Amendment") dated as of the 18 day
of June, 2002, between Harken Energy Corporation, a Delaware corporation (the
"Company"), and American Stock Transfer and Trust Company (successor to Mellon
Investor Services LLC, a New Jersey limited liability company (formerly known as
ChaseMellon Shareholder Services L.L.C.)), as Rights Agent (the "Rights Agent").

                                    RECITALS

         1. The Company and the Rights Agent have previously entered into that
certain Rights Agreement, dated as of April 6, 1998 (the "Agreement").

         2. Section 27 (Supplements and Amendments) of the Agreement provides,
in part, that, as long as the Rights are redeemable, the Agreement may be
supplemented or amended without the approval of any holders of Rights.

         3. The Company has effected and desires to continue to effect exchange
offers (collectively, the "Exchange Offers") for its outstanding 5% Convertible
Subordinated Notes due 2003 (the "Notes") pursuant to which the holders of the
Notes have received and will continue to receive various securities of the
Company in exchange for the Notes.

         4. The Company desires to amend the Agreement to ensure that no Person
will be deemed to be an Acquiring Person (as defined in the Agreement) as a
result of holding the Notes, participating in one or more of the Exchange Offers
or both.

                                    AGREEMENT

         Section 1.  Definitions.  All capitalized terms used but not defined
herein shall have the meanings given to them in the Agreement.

         Section 2.  Amended Definition. Pursuant to Section 27 of the Agreement
(Supplements and Amendments), the undersigned wish to amend Section 1(k) of the
Agreement (Certain Definitions -- Exempt Person) by deleting the existing
Section 1(k) in its entirety and replacing it with a new Section 1(k) to read as
follows:

         "(k) "Exempt Person" shall mean (i) the Company or any Subsidiary (as
         such term is hereinafter defined) of the Company, in each case
         including, without limitation, in its fiduciary capacity, or any
         employee benefit plan of the Company or of any Subsidiary of the
         Company, or any entity or trustee holding Common Stock for or pursuant
         to the terms of any such plan or for the purpose of funding any such
         plan or funding other employee benefits for employees of the Company or
         of any Subsidiary of the Company, and (ii) any Person who or which is
         or becomes the Beneficial Owner of 15% or more of the shares of Common
         Stock then outstanding as the result of such Person's Beneficial
         Ownership of the

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         Company's 5% Convertible Subordinated Notes due 2003, or acquisition
         from the Company of the Company's securities, and any shares of Common
         Stock issuable upon conversion, exchange or redemption thereof, in
         exchange for the Company's 5% Convertible Subordinated Notes due 2003
         held by such Person or both, unless and until such Person, while a
         Beneficial Owner of 15% or more of the shares of Common Stock then
         outstanding, shall become the Beneficial Owner of additional shares of
         Common Stock constituting 1% or more of the then outstanding shares of
         Common Stock other than pursuant to such an exchange, conversion or
         redemption."

         Section 3. Governing Law. This Amendment shall be deemed to be a
contract made under the laws of the State of Delaware and for all purposes shall
be governed by and construed in accordance with the laws of such State
applicable to contracts made and to be performed entirely within such State.

         Section 4. Counterparts.  This Agreement may be executed in any number
of counterparts and each of such counterparts shall for all purposes be deemed
to be an original, and all such counterparts shall together constitute but one
and the same instrument.

         IN WITNESS WHEREOF, the parties hereto have caused this Amendment to
Rights Agreement to be duly executed as of the day and year first above written.

                                  HARKEN ENERGY CORPORATION


                                  By: /s/ Bruce N. Huff
                                      ------------------------------------------
                                      Bruce N. Huff
                                      President and Chief Operating Officer

                                  AMERICAN STOCK TRANSFER AND TRUST
                                  COMPANY, as Rights Agent


                                  By: /s/ ______________________________________
                                      Name:_____________________________________
                                      Title:____________________________________

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