X0201 4 2004-01-20 0 0000730000 SUPERTEX INC SUPX 0001195891 SIEGEL RICHARD E 1 1 0 0 Executive Vice President Common Stock 2004-01-20 4 S 0 1500 21.15 D 21039 D Common Stock 2004-01-20 4 S 0 1500 20.98 D 19539 D Common Stock 2004-01-20 4 S 0 1000 21.07 D 18539 D Other Grants: ISO Option (to purchase common stock). Exercise price: $10.7500. Shares granted: 45,000. Shares currently exercisable: 9,000. 9,000 shares exercisable on 6/1/2004. 9,000 shares exercisable on 6/1/2005. 9,000 shares exercisable on 6/1/2006. 9,000 shares exercisable on 6/1/2007. Expiration date: 6/1/2008. Held direct. Other Grants: NQ Option (to purchase common stock). Exercise price $10.7500. Shares granted 9,000. Shares currently exercisable: 2,000. Expiration date: 6/1/2005. Held direct. Other Grants: NQ Option (to purchase common stock). Exercise price $15.5000. Shares granted 22,000. Shares currently exercisable: 17,600. 4,400 shares exercisable on 12/1/2004. Expiration date: 12/1/2006. Held direct. Other Grants: NQ Option (to purchase common stock). Exercise price: $12.5300. Shares granted: 22,000. Shares exercisable currently: 3,600. 3,600 shares exercisable on 6/1/2004. 3,600 shares exercisable on 6/1/2005. 11,200 shares exercisable on 6/1/2006. Expiration date: 6/1/2008. Held direct. Richard Siegel 2004-01-20