On the relationship between tariff levels and the nature of mergers

This paper employs an endogenous merger formation approach in a two-country oligopoly model of trade to examine the international linkages between the nature of mergers and tariff levels. Firms sell differentiated products and compete in a Bertrand fashion in product markets. We find two effects playing key roles in determining equilibrium market structure: the tariff saving effect and the protection gain effect. The balance between these two effects implies that, when foreign country practices free trade, unilateral tariff reduction by a domestic country yields international mergers irrespective of the substitutability levels. By contrast, when foreign tariffs are sufficiently high and products are close substitutes, national mergers obtain in the equilibrium. Therefore, the implications of unilateral trade liberalization on the equilibrium market structure depends on the trade regime in foreign country especially when products are close substitutes. Unlike this asymmetric result of unilateral trade liberalization, we find that when bilateral tariffs are sufficiently low, international mergers arise. These results fit well with the fact that global trade liberalization has been accompanied by an increase in international merger activities. Finally, from a welfare perspective, we show that international mergers are preferable to national mergers and thus social and private merger incentives become aligned together as trade gets bilaterally liberalized.