. . . Exhibit 4.50 FOURTH AMENDMENT TO CONTRACT ON PROCUREMENT OF TELKOM-2 SATELLITE NO.K.TEL 27/HK.920/UTA-00/2005, DATED 21 FEBRUARY 2005 Parties: 1. TELKOM; and 2. Orbital Sciences Corporation ("CONTRACTOR"). Preceding Agreements: 1. Main agreement - No.K.TEL.191/HK.810/UTA-00/2002 dated 24 October 2002; 2. Amendment No. 1 - No.K.TEL.260/HK.820/UTA-00/2003 dated 15 December 2003; 3. Amendment No. 2 - No.K.TEL.66/HK.920/UTA-00/2004 dated 31 March 2004; 4. Amendment No. 3 - No.Tel.248/HK.930/UTA-00/2004 dated 29 October 2004. Amended Provisions: 1. The parties agree to amend the contract price and payment, the fixed price for TELKOM-2 Satellite and the price for personnel training; 2. The parties agree to amend technical provisions on the training and internship program; 3. The parties agree to amend the milestone schedule payment. The parties also agree to amend the cumulative payment for milestone number 16.