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...

This paper studies the effects of the USPTO's patent secrecy program in World War II, under which over 11,000 U.S. patent applications were issued secrecy orders which halted examination and prohibited inventors from disclosing their inventions or filing in foreign countries. Secrecy orders were...