We investigate the causal effect of patent rights on cumulative innovation, using large-scale data that approximate the patent universe in its technological and economic variety. We introduce a novel instrumental variable for patent invalidation that exploits personnel scarcity in post-grant...

Because China has become one of the largest applicants of PCT patents, it is of interest to compare the quality of Chinese and non-Chinese applications. We extend a quality index based on internationally comparable citation data from international search reports (ISR) to consider foreign,...

Pharmaceutical firms typically enjoy market exclusivity for new drugs from concurrent protection of the underlying invention (through patents) and the clinical trials data submitted for market approval (through data exclusivity). Patent invalidation during drug development renders data...

We study the causal impact of invalidating marginally valid patents during post-grant opposition at the European Patent Office on affected inventors' subsequent patenting. We exploit exogenous variation in invalidation by leveraging the participation of a patent's original examiner in the...

How does antitrust enforcement against patent-based monopolies affect innovation? I address this question by empirically studying the US antitrust case against Xerox, the monopolist in the market for plain-paper copiers. In 1975, Xerox was ordered to license all its copier-technology patents in...