Price caps and efficiency in markets with adverse selection

Abstract

This article studies general economies with adverse selection in which symmetric companies supply (potentially multiple) plans to privately informed consumers and compete in terms of price schedules. I show that a basic price cap regulation, in which the price caps are endogenously determined by companies, discourages risk selection over efficient allocations, and therefore, equilibrium exists in every economy. Moreover, I demonstrate that in generalisations of Rothschild and Stiglitz (1976) and Wilson (1977) economies, companies earn zero profits in equilibrium, and every equilibrium allocation is efficient.