1 ITEM 14(A)3, EXHIBIT 21 SUBSIDIARIES OF THE REGISTRANT INCORPORATED PERCENT OF VOTING OR ORGANIZED SECURITIES OWNED NAME OF COMPANY UNDER LAWS OF BY TESORO - ----------------------------------------------------------------- ------------- ----------------- Tesoro Alaska Petroleum Company.................................. Delaware 100% Tesoro Alaska Pipeline Company................................... Delaware 100% Tesoro Bolivia Petroleum Company................................. Texas 100% Tesoro Exploration and Production Company........................ Delaware 100% Tesoro Gas Resources Company, Inc................................ Delaware 100% Tesoro Natural Gas Company....................................... Delaware 100% Tesoro Northstore Company........................................ Alaska 100% Tesoro Petroleum Companies, Inc.................................. Delaware 100% Tesoro Petroleum Distributing Company*........................... Louisiana 100% Tesoro Refining, Marketing & Supply Company...................... Delaware 100% - --------------- * Currently, Coastwide Marine Services, Inc. (see Note B of Notes to Consolidated Financial Statements in Item 8). Small or inactive subsidiaries are omitted from the above list. Such omitted subsidiaries, considered in the aggregate as a single subsidiary, would not constitute a "significant subsidiary" at the end of the year covered by this annual report.