This paper surveys the major changes in patent policy and practice that have occurred in the last two decades in the U.S., and reviews the existing analyses by economists that attempt to measure the impacts these changes have had on the processes of technological change. It also reviews the...

This paper examines the patenting behavior of firms in an industry characterized by rapid technological change and cumulative innovation. Recent evidence suggests that semiconductor firms do not rely heavily on patents, despite the strengthening of US patent rights in the early 1980s. Yet the...

How does the publication of patents affect innovation? We answer this question by exploiting a large-scale natural experiment--the passage of the American Inventor's Protection Act of 1999 (AIPA)--that accelerated the public disclosure of most U.S. patents by two years. We obtain causal...

This paper examines intellectual property litigation as a method of protection from patent-infringing imports. Claims against patent-infringing imports entering the United States may be filed before the International Trade Commission (ITC) or in district court. The ITC applies injunctions...

This paper examines the empirical anomaly that in a sample of 5811 patents on which US faculty are listed as inventors, 26% of the patents are assigned solely to firms rather than to the faculty member's university as is dictated by US university employment policies or the Bayh Dole Act. In this...

The recent surge in U.S. patenting and expansion of patentable subject matter has increased patent office backlogs and raised concerns that in some cases patents of insufficient quality or with inadequate search of prior art are being issued. At the same time patent litigation and its costs are...

The impacts of two recent changes in US patent policy depend on the length of time it takes for an invention to go through the examination process. Concerns over the distributional effects of these changes were expressed during policy debates. We use data on U.S. patent applications and grants...

A patent only protects an innovator from others producing the same product, but it does not protect him from others producing better products under new patents. Therefore, one may divide up the source of competition facing an innovator into within-patent competition, which results from...

We report the results of the first comparative study of the determinants and effects of patent oppositions in Europe and of re-examinations on corresponding patents issued in the United States. The analysis is based on a dataset consisting of matched EPO and US patents. Our analysis focuses on...

This essay is the introduction to a book of the same title, forthcoming in summer of 2021 from Oxford University Press. The purpose is to document the ways in which patent systems are products of battles over the economic surplus from innovation. The features of these systems take shape as...