Human capital use, innovation, patent protection, and economic growth in multiple regions

We provide the first theoretical analysis of the effects of human capital use, innovative activity, and patent protection, on economic growth in a model with many regions. In each region, consumers have constant relative risk-aversion preferences, there is no human capital growth, and there are three kinds of manufacturing activities involving the production of blueprints for inputs (machines), the inputs themselves, and a single final consumption good. Our analysis generates four results. For any given region, we first describe the balanced growth path (BGP) equilibrium and show that the BGP growth rate depends negatively on the rate at which patents expire. Second, we characterize the transitional dynamics in our model. Third, we determine the value of the patent expiry rate that maximizes the equilibrium growth rate of a region. Finally, we show that a policy of offering perpetual patent protection does not necessarily maximize social welfare in a region.