Companies that have this business model are pejoratively referred to as patent trolls. It is an integral part of the business model that patent licensing companies sue infringers that do not take a license. Furthermore, they may take advantage of the fact that many companies will pay a modest license fee (e.g. $100,000 to $1,000,000) for rights to a patent of questionable validity, rather than pay the high legal fees ($2,000,000 or more) to demonstrate in court that the patent is invalid. See also Open Invention Network (OIN) Patent Commons Project Piano roll blues Social networking patents References External links Software and Business Methods on the WIPO web site FFII Annotated Bibliography Softwarepatents.eu , an introduction to software patents in Europe and Germany (in German) Economic studies This paper includes a method of identifying software patents that has proved popular with organisations such as the Public Patent Foundation – commentary on the FTC "To Promote Innovation" report, 2003 (translated into English) Books Information Feudalism – Peter Drahos – 377-page play-by-play memoir of the story of Florian's part in the campaign over the EU software patent directive. Papers and presentations – Overview of the legal history and trends – How software came to be patentable in the United States