X0306 4 2012-12-12 0 0000909832 COSTCO WHOLESALE CORP /NEW COST 0000017940 CARSON BENJAMIN SR JOHN HOPKINS HOSPITAL 600 N. WOLFE ST., HARVEY 811 BALTIMORE MD 21287-8811 1 0 0 0 Common Stock 2012-12-12 4 A 0 456 98.31 A 22956 D Stock Option 40.69 2012-12-12 4 A 0 12915 40.69 A 2005-04-01 2015-04-01 Common Stock 12915 12915 D Represents additional restricted stock units ("RSUs") resulting from the upward adjustment of outstanding unvested RSUs by a factor of 1.0763 in connection with the $7.00 per share special cash dividend payable by the issuer to shareholders of record on December 10, 2012. The adjustment was required under the plan documents governing the grants. The RSUs reported are subject to the same vesting schedules as the original RSUs to which they relate. This option was previously reported as an option covering 12,000 shares at an exercise price of $43.79 per share and has been adjusted with a lower exercise price and an increased number of options, in connection with the dividend referenced in note 1. The number of outstanding options was increased by a factor of 1.0763, and the option exercise price was reduced by dividing the price by that same factor. The adjustment was required under the governing plan documents. This option is fully vested. Deanna K. Nakashima, attorney-in-fact 2012-12-13