X0303 4 2009-05-05 0000912145 AMERISTAR CASINOS INC ASCA 0001209843 WALSH PETER 3773 HOWARD HUGHES PKWY SUITE 490S LAS VEGAS NV 89169 1 SVP, GC, Chief Admin Officer Common Stock 2009-05-05 4 M 0 22496 6.9675 A 22496 I Family Trust Common Stock 2009-05-05 4 M 0 10512 11.5275 A 33008 I Family Trust Common Stock 2009-05-05 4 S 0 1613 22.13 D 31395 I Family Trust Common Stock 2009-05-05 4 S 0 3012 22.15 D 28383 I Family Trust Common Stock 2009-05-05 4 S 0 300 22.16 D 28083 I Family Trust Common Stock 2009-05-05 4 S 0 500 22.165 D 27583 I Family Trust Common Stock 2009-05-05 4 S 0 3500 22.20 D 24083 I Family Trust Common Stock 2009-05-05 4 S 0 74 22.21 D 24009 I Family Trust Common Stock 2009-05-05 4 S 0 700 22.22 D 23309 I Family Trust Common Stock 2009-05-05 4 S 0 2000 22.23 D 21309 I Family Trust Common Stock 2009-05-05 4 S 0 1000 22.24 D 20309 I Family Trust Common Stock 2009-05-05 4 S 0 1172 22.25 D 19137 I Family Trust Common Stock 2009-05-05 4 S 0 2700 22.26 D 16437 I Family Trust Common Stock 2009-05-05 4 S 0 300 22.27 D 16137 I Family Trust Common Stock 2009-05-05 4 S 0 100 22.28 D 16037 I Family Trust Common Stock 2009-05-05 4 S 0 400 22.30 D 15637 I Family Trust Common Stock 2009-05-05 4 S 0 100 22.31 D 15537 I Family Trust Common Stock 2009-05-05 4 S 0 5137 22.36 D 10400 I Family Trust Common Stock 2009-05-05 4 S 0 400 22.38 D 10000 I Family Trust Common Stock 2009-05-05 4 S 0 800 22.39 D 9200 I Family Trust Common Stock 2009-05-05 4 S 0 100 22.40 D 9100 I Family Trust Common Stock 2009-05-05 4 S 0 600 22.44 D 8500 I Family Trust Common Stock 2009-05-05 4 S 0 1600 22.45 D 6900 I Family Trust Common Stock 2009-05-05 4 S 0 1600 22.46 D 5300 I Family Trust Common Stock 2009-05-05 4 S 0 700 22.52 D 4600 I Family Trust Common Stock 2009-05-05 4 S 0 1200 22.54 D 3400 I Family Trust Common Stock 2009-05-05 4 S 0 400 22.57 D 3000 I Family Trust Common Stock 2009-05-05 4 S 0 100 22.58 D 2900 I Family Trust Common Stock 2009-05-05 4 S 0 300 22.59 D 2600 I Family Trust Common Stock 33800 D Stock Options (Right to Buy) 6.9675 2009-05-05 4 M 0 22496 0 D 2003-12-19 2012-12-20 Common Stock 22496 0 I Family Trust Stock Options (Right to Buy) 11.5275 2009-05-05 4 M 0 10512 0 D 2004-12-10 2013-12-11 Common Stock 10512 0 I Family Trust Securities owned by the Walsh Family Trust dated 9-11-03, of which Mr. Walsh and his spouse are co-trustees. Constitutes a grant of restricted stock units, each of which represents a right to receive one share of common stock. The restricted stock units vest in four equal, annual installments commencing on July 24, 2009. Option vested in five equal annual installments commencing on December 19, 2003. Option vested in five equal annual installments commencing on December 10, 2004. /s/ Peter C. Walsh 2009-05-07