This paper surveys the literature on merger policy in open economies. We first adopt a reduced-form approach to derive general insights on the scope for conflict between national antitrust authorities and on the gains from international merger policy coordination. Taking trade costs as given, we use standard oligopoly models to derive conditions on market structure, under which underenforcement or overenforcement of national merger policies can arise. We then study the interactions between merger policy and trade policy, and find that trade liberalization often leads to stricter national merger policies. We conclude by discussing empirical evidence on conflict between antitrust authorities.
In a two-country international trade model with oligopolistic competition, we study the conditions on market structure and trade costs under which a merger policy designed to benefit domestic consumers is too tough or too lenient from the viewpoint of the foreign country. We calibrate the model to match industry-level data in the U.S. and Canada. Our results suggest that at present levels of trade costs, merger policy is too tough in the vast majority of sectors. We also quantify the resulting externalities and study the impact of different regimes of coordinating merger policies at varying levels of trade costs.