Markets Linked by Rising Marginal Costs: Implications for Multimarket Contact, Recoupment, and Retaliatory Entry

This paper studies the effects on prices and welfare of multimarket contact when firms serve multiple markets from a single facility with rising marginal costs. Here a link is created between markets, even with independent demands: greater output in one market leads to a higher marginal cost and lower output in other markets; and multimarket contact can indeed lower welfare. Variations of the model can explain two other puzzling phenomena: “recoupment” – lower prices in one market “paid for” by higher prices in other markets; and “retaliatory entry” – the credible threat to enter a rival’s market if it enters yours.