We present a dynamic duopoly model of R&D with spillovers where industry concentration is endogenous. In our model, firms compete repeatedly in both the product market via Cournot competition and in imperfectly appropriable process R&D. The analysis highlights the effects of spillovers through...

We study a dynamic duopoly model of R\&D to analyze the impact of imperfect appropriability on market structure and welfare. We pursue this analysis by extending the Markov-Perfect dynamic industry model proposed by Ericson and Pakes (EP) (1995), through the introduction of a non-proprietary...