We investigate whether patents that are jointly held by legally independent companies help sustain product-market collusion. We use a simple model of repeated interactions to show that joint patents can serve collusive purposes. Our model generates two testable predictions: when joint patents...

We survey the economics literature on optimal patent design. We first outline the patent right and the basic economic effects of the patent on innovation. Models that use frictions instead of patents to generate rewards to innovation and models of trade secrecy are considered briefly. The patent...