Patent Pools and Litigation

Manuscript received December 2007; revised September 2008.Shortened Title: Patent Pools and LitigationThis paper develops a framework to analyze the incentives to form a patent pool or engage in cross-licensing arrangements in the presence of uncertainty about the validity and coverage of patents that makes disputes inevitable. It analyzes the private incentives to litigate and compares them with the social incentives. It shows that pooling arrangements can have the effect of sheltering invalid patents from challenges. This result has an antitrust implication that patent pools should not be permitted until after patentees have challenged the validity of each other’s patents if litigation costs are not too large.科学研究費補助金（特別推進研究） = Grant-in-Aid for Specially Promoted Research[Revised version]42 p