Spillover Effects of Intellectual Property Protection in the Interwar Aircraft Industry
利用1926年美国国会加强机身设计知识产权保护的政策实验，发现该保护促进了机身创新，但减缓了互补品航空发动机的创新，揭示了知识产权保护的溢出效应。
Abstract Can strengthening intellectual property protection for producers of one good affect innovation in other related goods? To answer this question, we exploit a unique policy experiment in the interwar military aircraft industry. Airframe designs had little intellectual property protection before 1926, but changes passed by Congress in 1926 provided airframe manufacturers with enhanced property rights over new designs. We show that granting property rights to airframe producers increased innovation in airframes, but slowed innovation in aero-engines, a complementary good where there was no change in the availability of intellectual property protection. We propose and test a simple theory that explains these patterns.