This excerpt taken from the SIRI DEF 14A filed Apr 21, 2006.
Functions of the Board of Directors
The responsibility of the Board of Directors is to supervise and direct the management of the Company in the interest and for the benefit of the Company's stockholders. To that end, the Board of Directors shall, acting directly or through Committees, have the following duties:
The Board of Directors has delegated to the Chief Executive Officer, working with the other executive officers of the Company, the authority and responsibility for managing the business of the Company in accordance with any specific plans, instructions or directions of the Board.
The Chief Executive Officer shall seek the advice and, in appropriate situations, the approval of the Board with respect to extraordinary actions to be undertaken by the Company, including those that would make a significant change in the financial structure or control of the Company, the acquisition or disposition of any significant business or the entry of the Company into a major new line of business.