Abstract
Recent empirical research demonstrates that cross-holding engenders significant anti-competitive effect even though it confers no decisive influence on the target firm. This research has obtained wide attention, which leads to both calls for and actual changes in antitrust policy. However, the effects of cross-holding on competition are not well established. This paper examines the collusive effect of cross-holding with asymmetry in cost functions across firms in an infinitely repeated Cournot duopoly game. The two firms have a different share of capital that affects marginal costs. We find that cross-holding facilitates collusion when a small firm (i.e., a firm with a small capital capacity) increases its passive ownership in a big firm (i.e., a firm with a large capital capacity), and the size of initial ownership is relatively small. Unexpectedly, collusion becomes more difficult to be sustained when a big firm increases ownership in a small firm, or when a small firm increases ownership in a big firm but the initial ownership is relatively large. Our result that cross-holding may either facilitate or hinder collusion, under certain circumstances, generates important implications for antitrust policy.