Share Contracts and Unobserved Ability

We present a model with a monopolistic landlord and tenants with unobservable ability. In this setting, the landlord should use a wage contract to extract the full surplus due to ability since a share or fixed rent contract leaves some of the surplus in the hands of the tenants. We combine this issue with a standard moral hazard problem on the tenants' side, which argues for a fixed rent contract. A share contract is an optimal compromise between these two forces.