Appropriation of Ideas and the Ramifications for Inventor Mobility

Knowledge diffusion contributes positively to innovation productivity and therefore economic growth. Inventor mobility has been identified as a key mechanism which can enhance the diffusion of knowledge. Therefore, it is no surprise that scholars explore the causes which can enhance or harm inventor mobility. In this paper we examine how the strengthening of patents (arguably the most important tool of appropriating innovation output) influences inventor mobility. We exploit a series, within a short time span, of court decisions, primarily by the Court of Appeals of the Federal Circuit (CAFC), between 1994 and 1995 and issuance of USPTO guidelines in 1996 that essentially facilitated the way in obtaining patents for software inventions. We exploit this set of institutional changes that strengthened intellectual property rights protection to examine the effect on mobility of inventors that specialize in software and computer sciences. We employ a recently compiled dataset of patents that disambiguates both inventor names and assignee names and offers unique identification numbers. We perform a difference-in-differences approach to estimate whether the rate of inventor mobility for software personnel changes differently than other technology fields.