Asset Market Equilibrium with Short-Selling.

This paper presents simple conditions and a simple proof of the existence of equilibrium in asset markets where short-selling is allowed and satiation is possible. Unlike standard nonsatiation assumptions, the one used here is weak enough to be reasonable in the mean-variance capital asset pricing model and in asset market models where investors maximize expected utility and where total returns to individual assets may be negative. Copyright 1989 by The Review of Economic Studies Limited.