Exhibit 4.2 Amendment No. 1 to Stock Purchase Agreement ------------------------------------------- THIS AMENDMENT NO. 1 TO STOCK PURCHASE AGREEMENT (this "Amendment") is dated as of March 31, 1998, by and among Motorola, Inc., a Delaware corporation...Stock Purchase Agreement • April 9th, 1998 • Motorola Inc • Radio & tv broadcasting & communications equipment • New York
Exhibit 4.4 REGISTRATION RIGHTS AGREEMENT ----------------------------- THIS REGISTRATION RIGHTS AGREEMENT (this "Agreement") is made as of , 1998, by and between Motorola, Inc., a Delaware corporation (the "Investor") and American Mobile Satellite...Registration Rights Agreement • April 9th, 1998 • Motorola Inc • Radio & tv broadcasting & communications equipment • New York
EXHIBIT 4.1 ------------- STOCK PURCHASE AGREEMENT FOR THE ACQUISITION OF MOTOROLA ARDIS ACQUISITION, INC. AND MOTOROLA ARDIS, INC. BY AMSC ACQUISITION COMPANY, INC. A WHOLLY-OWNED SUBSIDIARY OF AMERICAN MOBILE SATELLITE CORPORATIONStock Purchase Agreement • April 9th, 1998 • Motorola Inc • Radio & tv broadcasting & communications equipment • New York
Exhibit 4.3Participation Rights Agreement • April 9th, 1998 • Motorola Inc • Radio & tv broadcasting & communications equipment • New York
