This excerpt taken from the SIRI 10-K filed Mar 10, 2009.
Liberty Media Corporation has significant influence over our business and affairs and its interests may differ from ours.
Liberty Media Corporation holds preferred stock that is convertible into 40% of the issued and outstanding shares of our common stock. Pursuant to the terms of the preferred stock held by Liberty Media we cannot take certain actions, such as issue equity or debt securities, without the consent of Liberty Media. Additionally, upon expiration of the waiting period under Hart-Scott-Rodino Act, Liberty Media has the right to designate six members of our fifteen-member Board of Directors. We expect Liberty Media to designate these directors shortly. As a result, Liberty Media has significant influence over business and affairs. The interests of Liberty Media may differ from the interests of other holders of our common stock. The extent of Liberty Medias stock ownership in us also may have the effect of discouraging offers to acquire control of us and may preclude holders of our common stock from receiving any premium above market price for their shares that may be offered in connection with any attempt to acquire control of us.