Competition, innovation and racing for Priority at the U.S. Patent and Trademark Office

When two inventors file patent applications with overlapping, or “interfering ” claims, the U.S. patent rights are awarded to the applicant who establishes priority of invention. Patent interference cases are litigated at the U.S. Patent and Trademark Office’s Board of Patent Appeals and Interferences. The cases offer a unique window into competition between firms in research and innovation. This paper analyzes a random sample of interferences to investigate the impact of patent policies on innovation strategies. Our results contribute to the policy debate over the appropriate scope of patents and the revision of the U.S. patent priority structure. We find that while interference cases are in general rare, they are highly concentrated among chemical and biomedical firms. Biotechnology patent applications are so likely to be subject to interference litigation that a question arises about their character: a high rate of interfering means that multiple researchers are chasing a large patent prize associated with a well-defined research topic. This is turn suggests that either the scope of biotechnology patents is too broad or the bar for obviousness has been set too low