Washington, D.C. 20549
Proxy Statement Pursuant to Section 14(a) of the Securities
Exchange Act of 1934 (Amendment No.)
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Sirius XM Radio Inc.
(Name of Registrant as Specified In Its Charter)
(Name of Person(s) Filing Proxy Statement, if other than the Registrant)
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Sirius XM Radio Inc. Important Notice Regarding the Availability of Proxy Materials for the
Stockholder Meeting to Be Held on Wednesday, May 25, 2011 The Proxy Statement, Annual Report and other proxy materials are available at: This communication presents only an overview of the more complete proxy materials that are available to you on the Internet. We encourage you to access and review all of the m i portant n i formation contained in the proxy materials before voting. If you want to receive a paper or e-mail copy of these documents, you must request one. There is no charge to you for requesting a copy. Please make your request for a copy as instructed below on or Sirius XM Radio Inc. before May 15, 2011 to facilitate timely delivery. TO REQUEST PAPER COPIES OF PROXY MATERIALS: (please reference your 11-digit control number when requesting materials) By opting out to receive prin ted materia ls , your preference for future proxy mailings wil be kept on our file. Telephone: 1-888-313-0164 (outside of the U.S and Canada cal 201-680-6688) Email: (you must reference your 11-digit control number in your email) Internet: TO VOTE YOUR SHARES SEE INSTRUCTIONS ON REVERSE SIDE This is not a proxy card. You cannot use this notice to vote your shares. Dear Sirius XM Radio Inc. Stockholder: The 2011 Annual Meeting of Stockholders of Sirius XM Radio Inc. (the “Company”) wil l be held at the Auditorium at The Equitable Center, 787 Seventh Avenue, New York, New York, on Wednesday, May 25, 2011, at 9:00 A.M., (local tim e). Proposals to be considered at the Annual Meeting: (1) to elect eight Dir ectors to serve until the 2011 annual meeting of stockholders of the Company; (2) to ratify the appointment of KPMG LLP as our n i dependent regis tered public accountants for 2011; (3) to approve the advisory (non-bin ding) resolu tion relating to executive compensation; and (4) an advisory (non-bindin g) vote on frequency of future executive compensation votes. Sirius XM’s Directors recommend a vote “FOR” Items 1, 2 and 3. Sirius XM’s Directors recommend a vote for stockholder approval EVERY (3) YEARS on Item 4. The Board of Directors has fix ed the close of business on April 5, 2011 as the record date (the “Record Date”) for the determination of stockholders entitled to receive notice of and to vote at the Annual Meetin g or any adjournment(s) thereof. CONTROL NUMBER YOU MUST REFERENCE YOUR 11-DIGIT CONTROL NUMBER WHEN YOU REQUEST A PAPER COPY OF THE PROXY MATERIALS OR TO VOTE YOUR PROXY ELECTRONICALLY.97595



Meeting Location: The Equit able Center 787 Seventh Avenue New York, New York The following Proxy
Materials are available for you to review online: the Company’s Proxy Statement and 2010 Annual Report; and any amendments to the foregoin g materia ls that are required to be furnished to stockholders. To request a paper copy of the Proxy Materials: (you must reference your 11-digit control number lo cated on the reverse side of this form) Tele phone: 1-888-313-0164 (outside of the U.S and Canada call 201-680-6688) Email: (you must reference your 11-digit control number n i your email) Internet: The Proxy Materials for Sirius XM Radio Inc. are available to review at: Have this notice available when you request a PAPER copy of the Proxy Materials, when you want to view your proxy materia ls online, OR WHEN YOU WANT TO VOTE YOUR PROXY ELECTRONICALLY. HOW TO VOTE BY INTERNET We encourage you to review the proxy materia ls online before voting. Use the Internet to vote your shares. On the la nding page of the above website in the box a l beled “To Vote Your Shares by Internet” click on “Vote Now” to access the ele ctronic proxy card and vote your shares. Have this le tter in hand when you access the website. You will need to reference the 11-digit control number o l cated on the reverse side.97595