(Telecompaper) RPX said it has agreed to acquire the patents controlled by patent consortium Rockstar, for an undisclosed price. The Wall Street Journal said the purchase of the 4,000 patents will cost USD 900 million. Rockstar was formed in 2011 by Apple, Blackberry, Ericsson, Microsoft and Sony for the purpose of buying the 6,000 patents from the Nortel bankruptcy estate. Around 2,000 of the patents have already been distributed to various Rockstar owners. Upon closing, subject to regulatory approval and other customary conditions, RPX will receive license payments from a syndicate of over 30 companies, including Cisco and Google. Syndicate participants will receive non-exclusive licenses to the Rockstar patents, and RPX Clearinghouse will make the patents available for license to all other interested companies under fair, reasonable, and non-discriminatory (FRAND) terms. The RPX Clearinghouse syndicate includes a broad range of software and media providers, semi-conductor manufacturers, wireless carriers and wireline network operators, and original equipment manufacturers. Cisco said it developed a licensing model with RPX giving license access to those who chose not to join the RPX Clearinghouse syndicate. Google also helped develop the model while Microsoft and Apple worked with other Rockstar members Blackberry, Ericsson and Sony to reach consensus.