I introduce and analyze an equilibrium model of discovery, innovation, patenting and infringement. Firms that innovate must adapt complementary inputs, and are ex ante uncertain about whether adaptations will be costly and whether they will infringe other patents. If adaptation requires...

We identify welfare-optimal patent royalties in a model of costly imitation, entry and imperfect competition. When the social planner may impose a compulsory license, optimal royalties either blockade imitation, facilitating unregulated monopoly, or yield an aggregate-zero-profit "efficient"...

We use detailed data to estimate the private costs and private rents of United States patents for publicly-traded firms. In analyzing costs, we first introduce a novel theoretical model to interpret our estimates. We then combine lawsuit data from Derwent Litalert with non-practicing entity...

In a patent infringement suit, the alleged infringer wins with a ruling of either patent invalidity or non-infringement. It is ambiguous which of these outcomes is preferred by the alleged infringer. Invalidity may increase current-period competition, but simultaneously removes constraints to...

This paper describes a data set built to analyze patent litigation in the United States during 1929-2006. The data include all patents in published district court and appellate court decisions in which validity and/or infringement are at issue. We collect numerous patent-specific variables and...

This paper examines the impact of three patent damage regimes on licensing and competition between a patentee and imitator. We focus on product patents in a differentiated, duopoly setting. Neither per-unit royalties nor fixed fees under efficient licensing are unique in equilibrium. As a...