X0203 3/A 2009-03-23 2008-06-02 0 0001123647 ATP OIL & GAS CORP ATPG 0001436315 Morris George R. 4600 POST OAK PLACE SUITE 200 HOUSTON TX 77027 0 1 0 0 Chief Operating Officer Common Stock (Restricted) 15000 D Stock Option - Common Stock 57.31 2008-11-01 2012-10-31 Common Stock 3750 D Stock Option - Common Stock 57.31 2009-11-01 2012-10-31 Common Stock 3750 D Stock Option - Common Stock 57.31 2009-11-01 2012-10-31 Common Stock 3750 D Stock Option - Common Stock 57.31 2009-11-01 2012-10-31 Common Stock 3750 D Vesting schedule shown on Form 3 filed on 6/2/08 was subsequently amended to the following: 3750 shares vest on each of December 1, 2008 and December 1, 2009; 7500 shares vest on December 1, 2010. Form 3 filed on 6/2/08 reflected exercise price of $51.31, which was in error. George R. Morris 2009-03-23