We analyze horizontal mergers when the acquirer holds a passive partial ownership stake (PPO) in the target firm prior to the merger. We show that a PPO reduces the minimal synergy level necessary to make a merger beneficial for consumers. It follows that an antitrust authority ignoring existing...

The 1914 Clayton Act prohibited any acquisition whose effect may be to “substantially” lessen competition. International Shoe defined § 7's word “substantially” by saying that an acquisition's effect is “substantial” only if it “will injuriously affect the public.” This paper...

This paper examines whether cartel breakdown provokes a period of intensive merger activity amongst the former cartelists, designed to re-establish tacit collusion. Using a novel application of recurrent event survival analysis for a pooled sample of 84 European cartels, it finds that mergers...

An increasing body of empirical evidence is documenting trends toward rising concentration, profits, and markups in many industries around the world since the 1980s. Two major criticisms of these studies is that concentration and market shares are poorly measured at the national industry level...