Why Tie a Product Consumers Do Not Use?

We provide an explanation for tying not based on any of the standard arguments: efficiency, price discrimination, or exclusion. In our analysis a monopolist ties a complementary good to its monopolized good, but consumers do not use the tied good. The tie is profitable because it shifts profits from a complementary good rival to the monopolist. We show such tying is socially inefficient, but arises only when the tie is socially efficient in the absence of the rival. We relate this form of tying to several examples, discuss how it can also arise under competition, and explore its antitrust implications.