X0306 4 2012-08-29 0 0000908937 SIRIUS XM RADIO INC. SIRI 0001507934 Liberty Media Corp 12300 LIBERTY BOULEVARD ENGLEWOOD CO 80112 0 0 1 0 Common Stock 2012-08-29 4 P 0 8296557 2.528 A 505624429 I Through Wholly Owned Subsidiaries Common Stock 2012-08-30 4 P 0 6933455 2.523 A 512557884 I Through Wholly Owned Subsidiaries Common Stock 2012-08-31 4 P 0 9641569 2.521 A 522199453 I Through Wholly Owned Subsidiaries The price reflects a weighted average of purchases made at prices ranging from $2.52 to $2.53. The Reporting Person agrees to provide upon request by the staff of the Securities and Exchange Commission, the Issuer, or a security holder of the Issuer, information regarding the number of shares purchased at each separate price. The price reflects a weighted average of purchases made at prices ranging from $2.51 to $2.53. The Reporting Person agrees to provide upon request by the staff of the Securities and Exchange Commission, the Issuer, or a security holder of the Issuer, information regarding the number of shares purchased at each separate price. The price reflects a weighted average of purchases made at prices ranging from $2.50 to $2.53. The Reporting Person agrees to provide upon request by the staff of the Securities and Exchange Commission, the Issuer, or a security holder of the Issuer, information regarding the number of shares purchased at each separate price. LIBERTY MEDIA CORPORATION By: /s/ Craig Troyer Title: Vice President 2012-08-31