Patent reform has become, perhaps improbably, one of the most contentious issues facing Congress and the courts over the past six years. The fights range across a number of major issues, which not only separate patent owners from patent defendants and those who believe in innovation incentives from those who believe in market competition, but also divide patent owners themselves along both industry and technology lines. Advocates on both sides paint seemingly irreconcilable pictures of the patent system, either as a stable system with clearly defined legal rights essential to innovation or as a system rampant with litigation abuse by ?patent trolls? who use the legal system to divert money from innovative companies.

Far too much of this debate is based on anecdote and assumption, not real data. Pharmaceutical patent owners assume that most of the world works the way their industry does; so, too, do information technology (IT) companies. Patent trolls are variously portrayed as responsible for the majority of all patent lawsuits, for no more than two percent, or as mythical creatures that do not actually exist.

John R. Allison , Mark A. Lemley & J. H. Walker, Extreme Value or Trolls on Top? The Characteristics of the Most Litigated Patents,Stanford Public Law Working Paper No. 1407796, (2009)