Over the past forty years, there has been a remarkable transformation in horizontal merger enforcement in the United States. With no change in the underlying statute, the Clayton Act, there has been a dramatic decline in the weight given to market concentration by the federal courts and by the...

We study merger waves in vertically related industries where firms can engage in both vertical and horizontal mergers. Even though any individual merger would have been profitable, firms may refrain from merging for fear of negative impacts from other mergers. When they do merge, however, they...

This paper considers a general symmetric quantity-setting oligopoly where the "coefficient of cooperation" defined by Cyert and DeGroot (An Analysis of Cooperation and Learning in a Duopoly Context, 1973) is interpreted as the parameter indicating severity of competition. It is obtained that...

We study the effects of horizontal mergers when firms compete on quality and price. Two key factors are identified: (i) the magnitude of variable quality costs, and (ii) the relative magnitudes of cross-quality and cross-price effects on demand. The merging firms will increase (reduce) both...

Standard welfare analysis of horizontal mergers usually refers to two effects: the anticompetitive market power effect reduces welfare by enabling firms to charge prices above marginal costs, whereas the procompetitive efficiency effect increases welfare by reducing the costs of production...

It has been suggested that mergers, by increasing concentration, raise incentives to invest and hence are pro-competitive. To study the effects of mergers, we rewrite a game with simultaneous price and cost-reducing investment choices as one where firms only choose prices, and make use of...

Standard welfare analysis of horizontal mergers usually refers to two effects: the anticompetitive market power effect reduces welfare by enabling firms to charge prices above marginal costs, whereas the procompetitive efficiency effect increases welfare by reducing the costs of production...

We study upstream horizontal mergers and their potential efficiency gains. We show that an upstream horizontal merger can give rise to two efficiency-enhancing effects when firms trade through two-part tariffs. It increases R&D investments and decreases wholesale prices when downstream...

This paper investigates the effects of mergers on the product mix of multiproduct firms. Thus, we open the black box of post-merger efficiency improvements to reveal a new margin of adjustment along the product dimension. We analyze horizontal mergers in a theoretical model where oligopolistic...