Probabilistic Heterogeneous Patent Protection and Innovation Incentives

Using a general equilibrium framework, this paper shows that imperfect and heterogeneous patent protection across industries affects the relative innovation incentives of firms and the skill premium. It is found that tighter patent enforcement in some industries allows a patent enforcement externality effect to emerge, whereby varieties with relatively softer patent protection have relatively stronger innovation incentives. The theoretical mechanisms hold for a wide range of the elasticity of substitution between varieties and also hold in a North-South framework when IPR harmonization is considered. A numerical simulation shows that merging both endogenous technological change and institutional aspects in the form of imperfect and heterogeneous IPR protection can contribute to explaining the different innovation and wage inequality performances of the U.S. and the EU regions.