Backward vertical integration by a dominant firm into an upstream competitive industry causes both input and output prices to rise. The dominant firm's cost advantage may or may not offset the negative effect to higher prices on social welfare. Whether it does depends on a simple indicator...

We consider a model in which customers sequentially negotiate nonexclusive credit or insurance contracts from multiple risk-neutral firms in a market with free entry. Each contract is subject to moral hazard arising from a common noncontractible effort decision.