X0201 4 2003-07-30 0 0000311094 WESTAMERICA BANCORPORATION wabc 0001201517 TJIAN HANS T Y 0 1 0 0 Exec. Officer of Primary Subs. Common Stock 2003-07-30 4 S 0 2000 44.5 D 66177.5 I by Trust Common Stock 2003-07-30 4 S 0 2900 44.58 D 63277.5 I by Trust Common Stock 23430 I Deferred Common Stock 19641.492 I by ESOP Common Stock 43 I by Son By: Shirley Kolin, Attorney in Fact, For: Hans T Y Tjian 2003-07-31