This paper evaluates how different lengths of entry regulation impact market structure and market performance using a dynamic structural model. We formulate an oligopoly model in the tradition of Ericson and Pakes (1995) and allow entry costs to vary over time. Firms have the opportunity to...

Licensing in a patent thicket allows firms to either avoid or resolve hold-up. Firms' R&D incentives depend on whether they license ex ante or ex post. We develop a model of a patent portfolio race, which allows for endogenous R&D efforts, to study firms' choice between ex ante and ex post...