Cumulative innovation is central to economic growth. Do patent rights facilitate or impede such follow-on innovation? This paper studies the causal effect of removing patent protection through court invalidation on subsequent research related to the focal patent, as measured by later citations....

This paper studies the causal impact of patents on subsequent innovation by the patent holder. The analysis is based on court invalidation of patents by the U.S. Court of Appeals for the Federal Circuit, and exploits the random allocation of judges to control for the endogeneity of the judicial...

We study the interplay between transportation infrastructure, knowledge flows, and innovation. Exploiting historical data on planned portions of the interstate highway system, railroads, and exploration routes as sources of exogenous variation, we estimate the effect of U.S. interstate highways...

In many industries, broad cross-license agreements are considered a useful method to obtain freedom to operate and to avoid patent litigation. In this paper I study firm incentives to sign a broad cross-license as well as the duration of broad cross-license negotiations. I develop a model of...

Patents are a useful but imperfect reward for innovation. In sectors like pharmaceuticals, where monopoly distortions seem particularly severe, there is growing international political pressure to identify alternatives to patents that could lower prices. Innovation prizes and other non-patent...