Evaluating Market Reactions to Non-Practicing Entity Litigation

Emiliano Giudici and Justin Blount · 20 Vand. J. Ent. & Tech. 51

Abstract

An ongoing debate in patent law involves the role “non-practicing entities,” sometimes called “patent trolls,” serve in the patent system. Some argue they serve as valuable market intermediaries, while others contend they are a drain on innovation and an impediment to a well-functioning patent system. This Article adds to the data available in this debate by conducting an event study that analyzes the market reaction to patent litigation filed by large “mass aggregator” non-practicing entities against large publicly traded companies. This study advances the literature by attempting to reproduce the results of previous event studies done in this area with newer market data and by subjecting the event study results to more rigorous statistical analysis. In contrast to a previous event study, the Authors found that the market reacted little, if at all, to the patent litigation filed by large non-practicing entities.