press release

Tesoro granted license to make and sell gasolines subject to Unocal patents

The following news release was issued by Tesoro Petroleum Corporation

SAN ANTONIO, May 1, 2001--Tesoro Petroleum Corporation announced today that it has entered into a nonexclusive license agreement that allows the Company to make and sell all gasolines subject to patents held by Union Oil Company of California, a subsidiary of Unocal Corporation. The terms of the agreement are confidential.

"We are pleased to have reached an agreement with Unocal that sets a defined royalty for making and selling certain reformulated and California-specification gasolines, which are subject to their patents," stated Jerry H. Mouser, Executive Vice President, Commercial Marketing for Tesoro. "This agreement removes uncertainty regarding patent royalties as we expand our production and marketing of cleaner-burning gasolines."

Tesoro Petroleum Corporation is an independent refiner and marketer of petroleum products and provider of marine logistics services. Tesoro operates three refineries in the western U.S. with a combined capacity of 275,000 barrels per day. Tesoro's branded retail network is currently comprised of approximately 280 stations, of which approximately 100 are company owned and operated.

Contact: Tesoro Petroleum Corporation, San Antonio Susan Pirotina, 210/283-2631

Updated: May 2001