X0303 4/A 2010-05-11 2010-05-12 0000356213 PINNACLE ENTERTAINMENT INC. PNK 0001387049 Comer Stephen C C/O PINNACLE ENTERTAINMENT, INC. 8918 SPANISH RIDGE AVENUE LAS VEGAS NV 89148 1 0 0 0 Common Stock 2010-05-11 4 A 0 4500 0 A 4500 D Common Stock 3000 I By the Comer Family Trust Stock Options (Right to Buy) 13.44 2010-05-11 4 A 0 9000 0 A 2010-05-11 2020-05-11 Common Stock 9000 9000 D This amended Form 4 updates the form of ownership of shares of common stock beneficially owned by the reporting person to reflect that 3,000 shares of common stock are held indirectly by the Comer Family Trust, which had been reported in the reporting person's Form 4 filed on May 12, 2010 as being held directly by the reporting person. All of the stock options vested immediately on the date of grant. /s/ Elliot D. Hoops, Attorney-In-Fact for Stephen C. Comer 2010-05-20