Professor Louis Kaplow has argued that market delineation in antitrust should be abandoned because it is not useful in assessing market power or evaluating competitive effects. This article takes issue with that view, explaining that market delineation serves purposes overlooked by Professor...

On January 10, 2022, the U.S. Department of Justice and Federal Trade Commission issued a Request for Information on Merger Enforcement designed to elicit input in the preparation of guidelines replacing both the 2010 Horizontal Merger Guidelines and the 2019 Vertical Merger Guidelines. The RFI...

Inconvenient truths prevent econometric merger retrospective studies from substantially altering our understanding of competitive effects from horizontal mergers. Econometrics cannot definitively determine the effects of particular mergers, and if they could, econometric merger retrospectives...

The New Brandeis School renews debate on two fundamental antitrust policy questions: 1) what source of wisdom or set of values should inform antitrust rules; and 2) what criterion should govern antitrust case adjudication. In our view, the Chicago School's answer to the first question was right;...