This article empirically studies current claims that patent trolls, also known as patent assertion entities (PAEs) or non-practicing entities (NPEs), behave badly in litigation by bringing frivolous patent infringement suits and seeking nuisance fee settlements. The study explores these claims by examining the relationship between the type of patenteeplaintiffs and litigation outcomes (e.g., settlement, grant of summary judgment, trial, and procedural dispositions), while taking into account, among other factors, the technology of the patents being asserted and the identity of the lawyers and judges. The study finds significant heterogeneity among different patent holder entity types. Individual inventors, failed operating companies, patent holding companies, and large patent aggregators each have distinct litigation strategies largely consistent with their economic posture and incentives. These PAEs appear to litigate differently from each other and from operating companies. Accordingly, to the extent any patent policy reform targets specific patent plaintiff types, such reforms should go beyond the practicing entity versus non-practicing entity distinction and understand how the proposed legislation would impact more granular and meaningful categories of patent owners.
Christopher A. Cotropia, Jay Kesan & David Schwartz, Heterogeneity Among Patent Plaintiffs: An Empirical Analysis of Patent Case Progression, Settlement, and Adjudication, 15 J. Empirical Legal Stud. 80 (2018).