Incumbent firms have two basic possibilities to improve their competitive position in the product market: investment in R&D and the creation of entry barriers to the disadvantage of potential rivals, e.g. through lobbying activities, campaign contributions, bribes or the adoption of incompatible...

We construct a competitive model of innovation and growth under constant returns to scale. Previous models of growth under constant returns cannot model technological innovation. Current models of endogenous innovation rely on the interplay between increasing returns and monopolistic markets. In...