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...

We analyze the efficiency defense in merger control. First, we show that the relationship between exogenous efficiency gains and social welfare can be non-monotone. Second, we consider both endogenous mergers and endogenous efficiencies and find that merger proposals are largely aligned with a...

Using a spatial competition framework with three ex ante identical firms, we study the effects of a horizontal merger on quality, price and welfare. The merging firms always reduce quality. They also increase prices if demand responsiveness to quality is sufficiently low. The non-merging firm,...

This is a survey of the economic principles that underlie antitrust law and how those principles relate to competition policy. We address four core subject areas: market power, collusion, mergers between competitors, and monopolization. In each area, we select the most relevant portions of...

Recently there has been a notable increase in interest in antitrust law in much of the world. This chapter discusses antitrust policy toward horizontal mergers, the area of antitrust that has seen some of the most dramatic improvements in both economic tools and the application of economics in...

Contrary to the seminal paper of Horn and Wolinsky (1988), we demonstrate that upstream firms, which sell their products to competing downstream firms, do not always have incentives to merge horizontally. In particular, we show that when bargaining takes place over two-part tariffs, and not over...

This paper studies the interaction between horizontal mergers and price discrimination by endogenizing the merger formation process in the context of a repeated purchase model with two periods and three firms wherein firms may engage in Behaviour-Based Price Discrimination (BBPD). From a merger...

In an oligopolistic market, socially excessive entry takes place because of business-stealing effect which is a gain to the entrant but not to the industry as a whole. Similarly, in a sunset industry with declining demand, now socially excessive capacity cannnot be dissolved because everyone...

This paper studies the interaction between horizontal mergers and price discrimination by endogenizing the merger formation process in the context of a repeated purchase model with two periods and three firms wherein firms may engage in Behaviour-Based Price Discrimination (BBPD). From a merger...

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 ef-fect increases welfare by reducing the costs of production...