Assignment of Stock Warrant Rights

EXHIBIT 10.13


ASSIGNMENT OF STOCK WARRANT RIGHTS


This Assignment of Stock Warrant Rights (this "Assignment") is made effective as of May 31, 2000, by and among Crosby Capital LLC, a Texas limited liability company ("Warrant Rights Holder"), and Aviva Petroleum Inc., a Texas corporation ("Parent").


R E C I T A L


WHEREAS, pursuant to Sections 1.03 and 5.03 of that certain Loan, Settlement and Acquisition Agreement dated as of May 31, 2000 (the "Purchase Agreement"), by and among Warrant Rights Holder, and Parent, Aviva America, Inc., a Delaware corporation ("Aviva America"), Aviva Operating, Inc., a Delaware corporation ("Aviva Operating"), Aviva Overseas, Inc., a Delaware corporation ("Aviva Overseas"), Neo Energy Inc., a Texas corporation ("Neo"), Garnet Resources Corp., a Delaware corporation ("Garnet"), Argosy Energy, Inc., a Delaware corporation ("Argosy Energy"), and Argosy Energy International, a Utah limited partnership ("Argosy International"), Warrant Rights Holder agreed to transfer and deliver to Parent Warrant Rights Holder's right to purchase 1,500,000 shares of Parent's common stock (the "Warrant Rights").


A G R E E M E N T


NOW, THEREFORE, in consideration of the promises herein and in the Purchase Agreement, and other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the Warrant Rights Holder and Parent hereby agree as follows:


1. Transfer of Warrant Righ ...