AT&T has signed Sony Corp. as the latest licensee in its global MPEG-4 video-licensing program. Sony is AT&T's fourth licensee in Japan. The AT&T patents underlying the company's global licensing effort are considered essential to the practice of ISO/IEC 14496-2 and 14496-10, also known as MPEG-4, Part 2 and MPEG-4, Part 10 (H.264).http://www.att.com