patent terms of most licensed patents under the G.729 Consortium have expired, the remaining unexpired patents are usable on a royalty-free basis. G.729 includes patents from several companies which were until the expiry licensed by Sipro Lab Telecom, the authorized Intellectual Property Licensing Administrator for G.729 technology and patent pool. Past patent litigation AIM IP LLC, a California Limited Liability Company based in Mission Viejo, CA filed 17 patent infringement lawsuits in the Central District Courts of California accusing 22 different companies, including, Cisco Systems, Polycom and others of infringing U.S. Patent No. 5,920,853. The '853 patent was filed at the United States Patent and Trademark Office in 1996 by Rockwell International. The inventors listed on the '853 patent are Benyassine Adil, Su Huan-Yu and Shlomot Eyal. In 2000, the '853 patent was assigned by Rockwell International to Conexant Systems, an American-based software developer and fabless semiconductor company, which began as a division of Rockwell before being spun-off as its own public company. In 2010, the '853 patent was sold by Conexant Systems to AIM IP LLC, a California Limited Liability Company based in Mission Viejo. The '853 patent contains patent claims which cover lookup tables used in G.729. The patent has since expired and is no longer in force due to its patent term expiring. RTP payload type G.729 is assigned the static payload type 18 for RTP by IANA. The rtpmap parameter description for this payload type is "G729/8000". Both G.729a and G.729b use the same rtpmap description as G.729. G.729a and G.729b are indicated using annexb=no or annexb=yes, respectively. G.729 Annex B (G.729b) is the default in absence of parameter annexb in the Session Description Protocol. See also List of codecs Comparison of audio coding formats RTP audio video profile References External links ITU-T Recommendation G.729 - technical specification. G.729 Error Recovery for Internet Telephony ITU Patent database Sipro Lab Telecom (administers the patent pools for G.723.1 and G.729) Voiceage's G.729 implementation Audio codecs Speech codecs ITU-T recommendations ITU-T G Series Recommendations