X0304 4 2011-08-18 0000356213 PINNACLE ENTERTAINMENT INC. PNK 0001257587 SANFILIPPO ANTHONY MICHAEL C/O PINNACLE ENTERTAINMENT, INC. 8918 SPANISH RIDGE AVENUE LAS VEGAS NV 89148 1 1 0 0 President and CEO Common Stock 2011-08-18 4 P 0 40000 11.77 A 318750 D Common Stock 596 I By 401(k) Plan The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $11.65 to $11.86, inclusive. The reporting person undertakes to provide to Pinnacle Entertainment, Inc., any security holder of Pinnacle Entertainment, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the ranges set forth in footnote (1) to this Form 4. /s/ Elliot D. Hoops, Attorney-In-Fact for Anthony M. Sanfilippo 2011-08-18