In active investment climates where firms sequentially improve each other's products, a patent can terminate either because it expires or because a noninfringing innovation displaces its product in the market. We define the length of time until one of these happens as the effective patent life,...

We study how complementarities and intellectual property rights affect the management of knowledge workers. The main results relay when a firm will wish to sue workers that leave with innovative ideas, and the effects of complementary assets on wages and on worker initiative. We argue that firms...

The purpose of this paper is to link the propensity for innovative activity to cluster spatially to the stage of the industry life cycle. The theory of knowledge spillovers, based on the knowledge production function for innovative activity, suggests that geographic proximity matters most in...

We review the role of R&D in endogenous growth theory, and describe extant empirical research – macro and micro – bearing on R&D as an engine of growth. Taking R&D to be key, while recognizing the significance of economic incentives, emphasizes knowledge as an economic object and, more...