Prior research suggests that patents by mobile inventors are at higher risk of generating spillovers between departed and hiring firms. Despite extensive research on how inter-firm inventor mobility affects firms' learning and innovation, little is known about how firms protect their existing...

The size distribution of the domains of US-patented technological knowledge obeys an exponential law, revealing a disproportionable concentration of progress among larger domains. Our analyses suggest that this phenomenon is explained by a combination of two factors. First, domains’...