This study constructs a model of anticompetitive exclusive contracts in the presence of complementary inputs. A downstream firm transforms multiple complementary inputs into final products. When complementary input suppliers have market power, upstream competition within a given input market...

We develop a model of interlocking bilateral relationships between upstream firms (manufacturers)that produce differentiated goods and downstream firms (retailers) that compete imperfectly for consumers. Contract offers and acceptance decisions are private information to the contracting parties....

We review the Chicago school's single monopoly profit theory whereby an upstream monopolist cannot increase its profits through vertical integration as it has sufficient market power anyways. In our model the dominant supplier has full bargaining power and uses observable two-part tariffs. We...