X0306 4 2012-08-15 0000104207 WALGREEN CO WAG 0001188827 WASSON GREGORY D 108 WILMOT ROAD DEERFIELD IL 60015 1 1 0 0 President and CEO Walgreen Co. Common Stock 2012-08-15 4 M 0 16402 34.75 A 319755 D Walgreen Co. Common Stock 2012-08-15 4 S 0 16402 35.51 D 303353 D Walgreen Co. Common Stock 2012-08-15 4 I 0 468 35.56 D 0 I By spouse 401k Employee Stock Option (Right to Buy) 34.75 2012-08-15 4 M 0 16402 0 D 2005-09-01 2012-09-01 Common Stock 16402 0 D This transaction was effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person in October 2011. The price reported is a weighted average price. These shares were sold in multiple transactions at prices ranging from $35.35 to $35.64, inclusive. The reporting person undertakes to provide to the SEC staff, the issuer, or any securityholder of the issuer, upon request, information regarding the number of shares sold at each price within the range indicated. Includes shares received upon reinvestment of dividends and shares underlying Restricted Stock Units issued in lieu of dividends (through July 12, 2012) on outstanding Restricted Stock Units. /s/ Mark L. Dosier, attorney-in-fact 2012-08-17