This paper studies a market for a medical product in which there is perfect competition among health insurers, while the good is sold by a monopolist. Individuals differ in their severity of illness and there is ex post moral hazard. We consider two regimes: one in which insurers use coinsurance...

Two-sided platform firms serve distinct customer groups that are connected through interdependent demand, and include major businesses such as the media industry, banking, and the software industry. A well known textbook result in one-sided markets is that a government may increase a...