75.6% win rate for accused patent infringers.  Patentees lose 75.6% of the time against accused patent infringers.  “An empirical study of the results of patent litigation at the appellate level during the period 2002-2004. Dispositive case results, i.e., those not involving a remand on the merits, are compiled. Patent owners won 24.43% of the cases and accused infringers the remainder. The cases were further analyzed to determine the characteristics of winning and losing parties, including nationality, financial strength, location of principal offices, and several other factors.”   (Paul M. Janicke, University of Houston Law Center and Lilan Ren, University of Houston, “Who Wins Patent Infringement Cases?,” American Intellectual Property Law Association Quarterly Journal, Vol. 34, p. 1, 2006)

25% win rate for patent owners.  Patent owner long-term contested win rate.  “The long-term contested win rate for patent owners varies around 25 percent.” (LegalMetric press release, “LegalMetric Data Of KSR Effect On Patent Owner Win Rates,” eWorldwire, September 12, 2007)