We consider antitrust enforcement within the adversarial model used by the United States. We show that, under the adversarial system, the Antitrust Authority may try to prohibit mergers also in those cases in which litigation is ineØ cient. Even if market concentration and technological...

This paper studies mergers in two-sided markets by estimating a structural supply and demand model and performing counterfactual experiments. The analysis is performed on data for a merger wave in U.S. radio that occurred between 1996 and 2006. The paper makes two main contributions. First, I...