Something in common: Competitive dissimilarity and performance of rivals with common shareholders

Economists have long held that bringing firms under the umbrella of a common ownership structure creates monopolistic conditions that reduce competition. We challenge this view by investigating competition between firms in a nuanced manner. We examine the competitive and performance implications of “common institutional ownership,” which occurs when an institutional investor owns a sizeable number of shares in two publicly traded firms. We argue that rival firms with common ownership structures will engage in dissimilar competitive action repertoires to avoid direct competition with each other. Competing aggressively, but with dissimilar action repertoires, allows rivals to maintain high levels of performance. Competing with dissimilar action repertoires also helps ensure that performance disparity between the two firms remains low. In other words, competitive aggressiveness with dissimilar action repertoires yields an optimal competitive solution for rival firms and their common owners.