We consider multiple-principal multiple-agent models of moral hazard: Principals compete through mechanisms in the presence of agents who take unobservable actions. In this context, we provide a rationale for restricting principals to make use of simple mechanisms, which correspond to direct...

We consider multiple-principal multiple-agent games of incomplete information in which each agent can at most participate with one principal. In such contexts, we show that the restriction to direct truthful mechanisms involves a loss of generality, even if one only focuses on pure strategy...