This Agreement (this "Agreement") is made and entered into by and between Gilead Sciences, Inc., a Delaware
corporation ("Gilead") and Michael F. Bigham ("Employee"), effective as of May 24, 1996.
WHEREAS, Employee has tendered his resignation from all positions he holds with Gilead, effective as set forth
below, in order to accept a position as President and Chief Executive Officer of another company; and
WHEREAS, Gilead has accepted Employee's resignation, and wishes to provide him with certain benefits in
consideration of Employee's promises and covenants as contained herein;
NOW THEREFORE, in consideration of the mutual promises and covenants contained herein, it is hereby
agreed by and between the parties hereto as follows:
1. RESIGNATION. Employee hereby resigns from the position of Executive Vice President for Operations and
Chief Financial Officer and from all other positions he holds with the Company, effective as of July 1, 1996.
Gilead hereby accepts such resignation. From the effective date of this Agreement through July 1, 1996,
Employee shall remain in his current position at his current level of salary and benefits, subject to Gilead's policies
and procedures. After July 1, 1996, the parties shall have no further obligations to each other except as provided
in this Agreement or in other written agreements between Employee and Gilead.
2. STOCK OPTIONS. Exhibit A attached hereto sets forth all of the Gilead stock options held by Employee as
of the date of this Agreement, identified as Option A through Option G on Exhibit A (the "Options"). Employee
and Gilead agree that the Options are hereby amended as follows, effective as of the date of this Agreement:
(a) All of the unvested shares remaining under Option A (currently 32,396 shares) shall be accelerated and
Option A shall become exercisable in full upon the granting of marketing approval for Vistide-Registered
Trademark- (cidofovir injection) by the U.S. Food and Drug Administration, provided such approval occu