I develop a Schumpeterian model where the engine of growth is in the microeconomic structure of the patent races and derive new results on the determinants of growth. Under decreasing marginal productivity in the R&D sector, the equilibrium is characterized by small firms investing too little...

I develop a Schumpeterian model of endogenous growth with realistic features of the market for innovations as decreasing marginal productivity at the firm level and the possibility of wasteful duplications of resources between firms due to congestion at the industry level. Moreover, I consider...