TAG-ALONG AGREEMENT

TAG-ALONG AGREEMENT, dated as of November 13, 1998, by and among APOLLO INVESTMENT FUND IV, L.P., a Delaware limited partnership ("AIF IV"), APOLLO OVERSEAS PARTNERS IV, L.P., a Cayman Islands limited partnership ("AOP IV", and together with AIF IV, and including their respective successors and permitted assigns, the "Purchasers"), CD RADIO INC., a Delaware corporation (the "Company") and DAVID MARGOLESE (the "Stockholder").

WHEREAS, concurrently herewith, the Purchasers and the Company are entering into a Stock Purchase Agreement pursuant to which the Company will issue to the Purchasers shares of one or more series of preferred stock of the Company having an aggregate liquidation preference of up to$200,000,000 (the "Purchase Agreement"); capitalized terms used in this agreement and not otherwise defined shall have the meanings ascribed to them in the Purchase Agreement;

NOW THEREFORE, in consideration of the foregoing and the mutual covenants and agreements set forth herein, and as an inducement to the Purchasers to enter into the Purchase Agreement, the parties hereto agree as follows:

Section 1. Tag-Along Right. During the Tag-Along Period (as defined in Section 5), in the event the Margolese Sellers (or any of them) propose to make a Tag-Along Sale (as defined in Section 5), each of the Purchasers shall have the right to participate (a "Tag-Along Right") in such sale with respect to any shares of Common Stock (including shares obtainable upon the conversion of shares of Series A Preferred Stock and Series B Preferred Stock) held by them, on a pro rata basis (based on the ratio of the aggregate number of shares of Common Stock (or Common Stock equivalents) to be sold by Margolese Sellers (as defined in Section 5) to the aggregate number of shares of Common Stock beneficially owned by the Margolese Sellers participating in such sale immediately prior to such sale), for the greatest consideration per share of Common Stock and otherwise on the best terms by which any Margolese Seller sells its shares of Common Stock (or Common Stock equivalent).

Section 2. Notice and Procedure for Public Offerings. In the case of a Tag-Along Sale involving registration under the Securities Act of 1933, as amended (the "Securities Act"), by the Company of the Margolese Shares to be sold in the Tag-Along Sale, then if circumstances occur which give rise to the Tag-Along Right, the Purchasers shall have the right to participate therein as provided for in Sections 9.2 through 9.7 of the Purchase Agreement (without regard to the amount of time that that shall have elapsed from the Closing Date to the proposed date of the Tag-Along Sale); provided, however, that in the event the number of shares to be underwritten in any such offering is limited or "cut-back" pursuant to Section 9.2 (b) of the Purchase Agreement, the parties hereto agree that the Margolese Sellers and the Purchasers shall be cut-back proportionally to preserve the ratio of (x) the number of shares of Common Stock (or Common Stock equivalents) the Margolese Sellers desire to have included in such sale over (y) the number of shares the Purchasers desire to have included in such sale (the "Relative Ratio"), and each of the Margolese Sellers agree to voluntarily reduce the number of Margolese Shares to be included in such registration in order to preserve the Relative Ratio.

详细内容见附件