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                                                                     Exhibit 4.1

                       FIRST AMENDMENT TO RIGHTS AGREEMENT


     This First Amendment to Rights Agreement (this "Amendment") is made and
entered into as of April 3, 2002, by and between Vintage Petroleum, Inc., a
Delaware corporation (the "Corporation"), and Mellon Investor Services LLC
(formerly known as ChaseMellon Shareholder Services, L.L.C.), a New Jersey
limited liability company, as Rights Agent (the "Rights Agent").

     WHEREAS, the Corporation and the Rights Agent have entered into that
certain Rights Agreement dated as of March 16, 1999 (the "Rights Agreement");

     WHEREAS, the Board of Directors of the Corporation has authorized and
declared a dividend of one preferred share purchase right (a "Right") for each
Common Share of the Corporation outstanding on April 5, 1999, each Right
representing the right to purchase one one-thousandth of a Preferred Share, upon
the terms and subject to the conditions set forth in the Rights Agreement, as
amended hereby, and has further authorized and directed the issuance of one
Right with respect to each Common Share that shall become outstanding between
the Record Date and the earliest of the Distribution Date, the Redemption Date
and the Final Expiration Date;

     WHEREAS, the Board of Directors of the Corporation has determined that it
is in the best interest of the Corporation and its stockholders to effect
certain amendments to the Rights Agreement;

     WHEREAS, pursuant to Section 27 of the Rights Agreement, the Corporation
may, prior to the Distribution Date, amend the Rights Agreement without the
approval of any holders of Rights to make any provisions with respect to the
Rights which the Corporation deems necessary or desirable;

     WHEREAS, the Distribution Date has not yet occurred as of the date hereof;
and

     WHEREAS, the Corporation wishes to amend the Rights Agreement in the manner
set forth below.

     NOW, THEREFORE, in consideration of the premises and the mutual agreements
set forth herein, the Corporation and the Rights Agent hereby agree as follows:

     1.   Definitions; References. All capitalized terms used herein, unless
otherwise defined herein, shall have the meanings given them in the Rights
Agreement, and each reference in the Rights Agreement to "this Agreement,"
"hereof," "herein," "hereunder" or "hereby" and each other similar reference
shall be deemed to refer to the Rights Agreement as amended hereby. All
references to the Rights Agreement in any other agreement between or among any
of the parties hereto relating to the transactions contemplated by the Rights
Agreement shall be deemed to refer to the Rights Agreement as amended hereby.

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     2.   Amendments.

     (a)  The definition of "Acquiring Person" in Section 1(a) of the Rights
Agreement is hereby amended and restated in its entirety as follows:

          "(a) "Acquiring Person" shall mean any Person who or which, together
     with all Affiliates and Associates of such Person, shall be the Beneficial
     Owner of 10% or more of the then outstanding Common Shares (other than as a
     result of a Permitted Offer) or was such a Beneficial Owner at any time
     after the date hereof, whether or not such Person continues to be the
     Beneficial Owner of 10% or more of the then outstanding Common Shares.
     Notwithstanding the foregoing: (i) the term "Acquiring Person" shall not
     include (A) the Corporation, (B) any Subsidiary of the Corporation, (C) any
     employee benefit plan of the Corporation or of any Subsidiary of the
     Corporation, (D) any Person or entity organized, appointed or established
     by the Corporation for or pursuant to the terms of any such plan, or (E)
     any Grandfathered Stockholder; and (ii) no Person shall be deemed to be an
     "Acquiring Person" either (A) as a result of the acquisition of Common
     Shares by the Corporation which, by reducing the number of Common Shares
     outstanding, increases the proportional number of shares beneficially owned
     by such Person together with all Affiliates and Associates of such Person
     (except that if (1) a Person would become an Acquiring Person (but for the
     operation of this subclause A) as a result of the acquisition of Common
     Shares by the Corporation, and (2) after such share acquisition by the
     Corporation, such Person, or an Affiliate or Associate of such Person,
     becomes the Beneficial Owner of any additional Common Shares (other than
     pursuant to a dividend or distribution paid or made by the Corporation on
     the outstanding Common Shares or pursuant to a split or subdivision of the
     outstanding Common Shares), then such Person shall be deemed an Acquiring
     Person), or (B) if (1) within eight days after such Person would otherwise
     have become an Acquiring Person (but for the operation of this subclause
     B), such Person notifies the Board that such Person did so inadvertently
     and (2) within two days after such notification, such Person is the
     Beneficial Owner of less than 10% of the outstanding Common Shares.
     Notwithstanding the foregoing, any Person who would otherwise qualify as an
     Acquiring Person as of April 3, 2002, pursuant to the foregoing provisions
     of this paragraph (a) shall not be deemed to be an Acquiring Person for any
     purpose of this Agreement on and after such date unless and until such
     Person, together with all Affiliates and Associates of such Person, shall
     be the Beneficial Owner of a percentage of Common Shares then outstanding
     in excess of the sum of 1% and the percentage of Common Shares beneficially
     owned by such Person and all Affiliates and Associates of such Person as of
     April 3, 2002; provided, however, that the foregoing exclusion shall cease
     to apply with respect to any Person at such time as such Person, together
     with all Affiliates and Associates of such Person, ceases to beneficially
     own 10% or more of the then outstanding Common Shares."


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     (b)  Section 3(d) of the Rights Agreement is hereby amended to change the
legend contained therein to read in its entirety as follows:

     "This certificate also evidences and entitles the holder hereof to certain
     Rights as set forth in a Rights Agreement between Vintage Petroleum, Inc.
     and Mellon Investor Services LLC, dated as of March 16, 1999, as amended by
     the First Amendment to Rights Agreement dated as of April 3, 2002, and as
     the same may be further amended from time to time (the "Rights Agreement"),
     the terms of which are hereby incorporated herein by reference and a copy
     of which is on file at the principal executive offices of Vintage
     Petroleum, Inc. Under certain circumstances, as set forth in the Rights
     Agreement, such Rights will be evidenced by separate certificates and will
     no longer be evidenced by this certificate, may be redeemed or exchanged or
     may expire. Vintage Petroleum, Inc. will mail to the holder of this
     certificate a copy of the Rights Agreement without charge after receipt of
     a written request therefor. As set forth in the Rights Agreement, Rights
     issued to, or held by, any Person who is, was or becomes an Acquiring
     Person or an Affiliate or Associate thereof (as such terms are defined in
     the Rights Agreement) and certain related Persons, whether currently held
     by or on behalf of such Person or by any subsequent holder, may become null
     and void."

     (c)  Section 26 of the Rights Agreement is hereby amended by changing the
addresses for notices to the Corporation and the Rights Agent, respectively, to
the following:

     "Vintage Petroleum, Inc.
     110 West Seventh Street
     Tulsa, Oklahoma 74119
     Attention:  General Counsel

     Mellon Investor Services LLC
     44 Wall Street, 6th Floor
     New York, New York  10005
     Attention:  Yvonne D. Benn"

     (d)  The Rights Agreement and Exhibit B thereto are hereby amended to
replace the references therein to "ChaseMellon Shareholder Services, L.L.C." to
"Mellon Investor Services LLC".

     (e)  The last sentence of the first paragraph of the Summary of Rights to
Purchase Preferred Shares set forth in Exhibit C to the Rights Agreement is
hereby amended and restated in its entirety to read as follows:

          "The description and terms of the rights are set forth in a Rights
     Agreement, dated as of March 16, 1999, between the Corporation and Mellon
     Investor Services LLC, as Rights Agent, as amended by the First Amendment
     to Rights Agreement, dated as of



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     April 3, 2002, and as the same may be further amended from time to time
     (the "Rights Agreement")."

     (f)  The second paragraph of the Summary of Rights to Purchase Preferred
Shares set forth in Exhibit C to the Rights Agreement is hereby amended to
change "15%", as it appears in clause (i) thereof, to "10%".

     (g)  The last paragraph of the Summary of Rights to Purchase Preferred
Shares set forth in Exhibit C to the Rights Agreement is hereby amended and
restated in its entirety to read as follows:

     "A copy of the Rights Agreement has been filed with the Securities and
     Exchange Commission as an Exhibit to the Corporation's Registration
     Statement on Form 8-A dated March 22, 1999. A copy of the First Amendment
     to Rights Agreement has been filed with the Securities and Exchange
     Commission as an Exhibit to the Corporation's Amendment No. 1 to
     Registration Statement on Form 8-A dated April 3, 2002. A copy of the
     Rights Agreement and the First Amendment thereto is available free of
     charge from the Corporation. This summary description of the Rights does
     not purport to be complete and is qualified in its entirety by reference to
     the Rights Agreement and the First Amendment thereto, which are hereby
     incorporated herein by reference."

     3.   Severability. If any term, provision, covenant or restriction of this
Amendment is held by a court of competent jurisdiction or other authority to be
invalid, void or unenforceable, the remainder of the terms, provisions,
covenants and restrictions of this Amendment shall remain in full force and
effect and shall in no way be affected, impaired or invalidated.

     4.   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; except that all
provisions regarding the rights, duties and obligations of the Rights Agent
shall be governed by and construed in accordance with the law of the State of
New York applicable to contracts made and to be performed entirely within such
state.

     5.   Counterparts. This Amendment may be executed in any number of
counterparts, 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.

     6.   Existing Terms. The existing terms and conditions of the Rights
Agreement shall remain in full force and effect except as such terms and
conditions are specifically amended or conflict with the terms of this
Amendment.



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     IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
duly executed by their respective authorized officers, all as of the day and
year first above written.

                               VINTAGE PETROLEUM, INC.


                               By: /s/ William C. Barnes
                                   ---------------------------------------------
                                   Name: William C. Barnes
                                   Title: Executive Vice President

                               MELLON INVESTOR SERVICES LLC


                               By: /s/ Edgar Ambert
                                   ---------------------------------------------
                                   Name: Edgar Ambert
                                   Title: Client Service Manager



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