FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
Liberty Media Corp
  2. Issuer Name and Ticker or Trading Symbol
SIRIUS XM RADIO INC. [SIRI]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director __X__ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
(Last)
(First)
(Middle)
12300 LIBERTY BOULEVARD
3. Date of Earliest Transaction (Month/Day/Year)
08/10/2012
(Street)

ENGLEWOOD, CO 80112
4. If Amendment, Date Original Filed(Month/Day/Year)
6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)
2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code
(Instr. 8)
4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)
5. Amount of Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 3 and 4)
6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)
7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V Amount (A) or (D) Price
Common Stock 08/10/2012   P   43,000,000 A $ 2.452 (1) 405,548,700 I Through Wholly Owned Subsidiaries
Common Stock 08/13/2012   P   15,800,000 A $ 2.496 (2) 421,348,700 I Through Wholly Owned Subsidiaries
Common Stock 08/14/2012   P   31,170,000 A $ 2.517 (3) 452,518,700 I Through Wholly Owned Subsidiaries

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 3)
2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction Code
(Instr. 8)
5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)
6. Date Exercisable and Expiration Date
(Month/Day/Year)
7. Title and Amount of Underlying Securities
(Instr. 3 and 4)
8. Price of Derivative Security
(Instr. 5)
9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 4)
10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)
11. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares
Forward purchase contract (obligation to buy) (4) (5) 08/10/2012   J/K(4)(5)   41,087,753   10/11/2012 10/11/2012 Common Stock 41,087,753 $ 0 41,087,753 I Through Wholly Owned Subsidiaries

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
Liberty Media Corp
12300 LIBERTY BOULEVARD
ENGLEWOOD, CO 80112
    X    

Signatures

 LIBERTY MEDIA CORPORATION By: /s/ Craig Troyer Title: Vice President   08/14/2012
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) The price reflects a weighted average of purchases made at prices ranging from $2.38 to $2.49. 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.
(2) The price reflects a weighted average of purchases made at prices ranging from $2.48 to $2.50. 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.
(3) The price reflects a weighted average of purchases made at prices ranging from $2.49 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.
(4) On June 29, 2012, Liberty Radio, LLC, a wholly-owned subsidiary of the Reporting Person, entered into a forward purchase contract (the "Forward Contract") with an unaffiliated counterparty covering up to a maximum of 220,000,000 notional shares of the Issuer's Common Stock. The exact number of shares to be covered by the Forward Contract is to equal the number purchased by the counterparty to establish its initial hedge. On August 10, 2012, the unaffiliated counterparty completed its initial hedge, and the number of notional shares of Common Stock covered by the Forward Contract has been fixed at 41,087,753 shares. Under the Forward Contract, the expiration date is to be October 11, 2012, or 60 days after the completion of the counterparty's initial hedge. The base price under the Forward Contract is approximately $2.047 per share.
(5) The Forward Contract provides for physical settlement upon expiration, with the Reporting Person retaining the right to elect cash settlement instead. In the case of physical settlement, the "forward price" will equal the value average weighted price of the shares of the Issuer's Common Stock during the initial hedging period plus a commission (the "base price"), plus an amount equal to the counterparty's internal funding costs plus a spread. If cash settlement is elected, (i) if the cash settlement price (which would be based on the price at which the counterparty unwinds its hedge) exceeds the forward price, then the counterparty will be obligated to pay the difference to the Reporting Person, and (ii) if the cash settlement price is less than the forward price, then the Reporting Person will be obligated to pay the difference to the counterparty.

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