We amend Hopenhayn's model of equilibrium industry dynamics by explicitly modeling the firm's investment choice and by introducing aggregate fluctuations. Our main goal is to study the model's implications for the cyclical behavior of entry, exit, and the cross--section of operating firms. We...

We study an optimal patent problem in the spirit of Hopenhayn, et al (2006), but where all innovations arise from two repeated innovators. Following Hopenhayn, et al (2006) we divide patent regimes into those that are exclusive, in the sense that only one firm ever has a claim on the current...