Altonio O’Shea Douglas, federal prisoner #23798-077, appeals the district court’s denial of his second motion for modification of sentence pursuant to 18 U.S.C. § 3582(c)(2). Douglas argues that he is entitled to a reduced sentence under Amendment 505 to the Sentencing Guidelines and the Supreme Court’s decision in United States v. Booker, 543 U.S. 220, 125 S.Ct. 738, 160 L.Ed.2d 621 (2005).

A district court exercises sound discretion in determining whether to grant a 18 U.S.C. § 3582(c)(2) motion, and we review its decision for abuse of discretion only. United States v. Gonzalez-Balderas, 105 F.3d 981, 982 (5th Cir. 1997). The district court did not abuse its discretion in denying Douglas’s motion. This court’s previous opinion denying relief under § 3582(c)(2) with respect to Douglas’s Amendment 505 claim is the law of the case. See United States v. Becerra, 155 F.3d 740, 752-52 (5th Cir. 1998). Douglas’s Booker claim is not cognizable in the context of a 18 U.S.C. § 3582(c)(2) motion because it is not based on a retroactive amendment to the Guidelines. See United States v. Shaw, 30 F.3d 26, 29 (5th Cir. 1994).

AFFIRMED.