<PAGE>
 
             responsible for health care continuation rights under Section 4980B
             of the federal tax code and Sections 601-609 of ERISA for those
             Cimarron Employees.

  10.3  No Third Party Beneficiaries.  No provisions of this Article 10 shall
create any third party beneficiary or other rights in any employee or former
employee (including any beneficiary or dependent thereof) of the Seller in
respect to continued employment or resumed employment with either the Buyers or
Seller and no provision of this Article 10 shall create any such rights in any
employee or former employee (including any beneficiary or dependent thereof) of
Seller or Buyer with respect to any benefits that may be provided directly or
indirectly in any benefit plan or other employee benefit plan or program.

          IN WITNESS WHEREOF, the authorized representatives of the Parties
executed this Agreement on the date indicated in the opening paragraph of this
Agreement.


CONOCO INC.          ENOGEX PRODUCTS CORPORATION
 
By:  /s/ James L. Rockwell                      By:  /s/ Roger A. Farrell
     ---------------------                           --------------------
     James L. Rockwell                               Roger A. Farrell
     Manager - Business & Strategic Development      Attorney in Fact
     Natural Gas & Gas Products
 

CIMARRON GAS HOLDING COMPANY

By:  /s/ Joseph L. von Rosenberg III
     -------------------------------
     Joseph L. von Rosenberg III
     Vice President

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