Partial price discrimination by an upstream monopolist

We analyze third degree price discrimination by an upstream monopolist to a continuum of heterogeneous downstream firms. The novelty of our approach is to recognize that customizing prices may be costly. As a consequence, partial price discrimination arises in equilibrium; in particular,we showthat inefficient downstream firms receive personalized prices whereas efficient firms are charged a uniform price. The extreme cases of complete price discrimination and uniform price arise in our setting as particular cases, depending on the cost of customizing prices. -- price discrimination ; input markets