X0303 4 2009-07-24 1 0000819050 VICAL INC VICL 0001044321 MARXE AUSTIN W & GREENHOUSE DAVID M C/O SPECIAL SITUATIONS FUNDS 527 MADISON AVENUE, SUITE 2600 NEW YORK NY 10022 0 0 1 0 Common Stock 2009-07-24 4 S 0 100000 3.1607 D 4445965 I By Limited Partnerships Common Stock 2009-07-24 4 S 0 50000 3.1663 D 4395965 I By Limited Partnerships Common Stock 2009-07-24 4 S 0 100000 3.1847 D 4295965 I By Limited Partnerhips Common Stock 2009-07-27 4 S 0 200000 3.445 D 4095965 I By Limited Partnerships Common Stock 2009-07-27 4 S 0 25000 3.4596 D 4070965 I By Limited Partnerships Common Stock 2009-07-27 4 S 0 50000 3.5063 D 4020965 I By Limited Partnerhips Common Stock 2009-07-27 4 S 0 126200 3.5561 D 3894765 I By Limited Partnerships Common Stock 2009-07-27 4 S 0 150000 3.6124 D 3744765 I By Limited Partnerships This is a joint filing by Austin W. Marxe (Marxe) and David M. Greenhouse (Greenhouse). They share voting and investment control over all securities owned by Special Situations Fund III QP, L.P (QP), Special Situations Cayman Fund, L.P. (Cayman), Special Situations Private Equity Fund, LP (PE) and Special Situations Life Sciences Fund, L.P. (LS). 2,030,620 shares of Common Stock are owned by QP, 617,669 shares of Common Stock are owned by Cayman, 129,519 shares of Common Stock are owned by PE and 966,957 shares of Common Stock are owned by LS. The interest of Marxe and Greenhouse in the shares of Common Stock owned by QP, Cayman, PE and LS are limited to the extent of his pecuniary interest. Austin W. Marxe 2009-07-28 David M. Greenhouse 2009-07-28