Patent protection, externalities, and income inequality

This paper develops a Schumpeterian growth model with considering consumption and leisure externalities. The main purpose of this study is to investigate the effect of patent protection policy on growth and inequality, as well as the interaction between policy effect and externalities. According to the log form utility function specification, this means that the elasticity of intertemporal substitution is unity. The following are the key findings of this paper. Patent protection policy encourages innovation and increases employment in the R&D industry, which enhances economic growth while increasing income inequality. In regard to externalities, an increase in the degree of consumption (leisure) externalities results in a higher (lower) growth rate and more (smaller) income inequality. When consumption (leisure) externality is greater intensity, the growth effect of patent protection policy becomes stronger (weaker), while its influence on expanding income inequality lessens (enhances). Finally, both the Pareto optimal patent protection policy and the optimal patent policy under the maximization of social welfare positively correlate with consumption externalities, but negatively correlate with leisure externalities.