We propose a simple method for predicting price effects from mergers between branded retail chains competing in many local markets. When past mergers created markets with the same number of brands but different numbers of brand owners, price data at a single point in time exhibit between-market...

European enforcers have brought high-profile antitrust cases against the tech giants, and both activists and members of Congress are calling for action in the United States. This short note identifies ten hard-wired differences between the European and American enforcement regimes that make very...

Horizontal mergers give rise to unilateral anticompetitive effects if they cause the merged firm to act less intensely competitive than the merging firms, while non-merging rivals do not alter their competitive strategies. This chapter describes the economic theory underlying unilateral...