-quality menus to segment the market. We show that, contrary to the Coase conjecture for the homogeneous durable good monopoly …

absolute margin. We derive these results in both a monopoly model and a variety of different competitive models. We conclude …

This paper investigates how the tying of complementary products can be used to preserve and extend monopoly positions …. We first show how a firm that is a monopolist of a product in the current period can use tying to preserve its monopoly … monopoly position into a newly emerging market. The analysis focuses on the importance of entry costs and network externalities …