Collusion under imperfect monitoring with asymmetric firms

Abstract

We explore the effects of asymmetries in capacity constraints on collusion where market demand is uncertain and where firms’ sales and prices are private information. We show that all firms can infer when at least one firm’s sales are below some firm-specific ‘trigger level’. When firms use this public information to monitor the collusive agreement, price wars may occur on the equilibrium path. Symmetry facilitates collusion but, if price wars are sufficiently long, then the optimal collusive prices of symmetric capacity distributions are lower on average than the competitive prices of asymmetric capacity distributions. We draw conclusions for merger policy.