This paper studies competing mechanisms with limited commitment over infinite horizon. Between a mechanism and the agent, there is perfect monitoring, but each mechanism can have arbitrary signals about the interaction between other mechanisms and the agent. I show that if the agent's type is...

This paper studies collusion in repeated auctions when bidders communicate prior to each stage auction. The paper presents a folk theorem for independent and correlated private signals and general interdependent values. Specifically, it identifies conditions under which an equilibrium collusion...