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Mergers and acquisitions are a major component of antitrust law and practice. The U.S. antitrust agencies spend a majority of their time on merger enforcement. The focus of most merger review at the agencies involves horizontal mergers, that is, mergers among firms that compete at the same level of production or distribution.

Vertical mergers combine firms at different levels of production or distribution. In the simplest case, a vertical merger joins together a firm that produces an input (and competes in an input market) with a firm that uses that input to produce output (and competes in an output market).

Over the years, the agencies have issued Merger Guidelines that outline the type of analysis carried out by the agencies and the agencies’ enforcement intentions in light of state of the law. These Guidelines are used by agency staff in evaluating mergers, as well as by outside counsel and the courts.

Guidelines for vertical mergers were issued in 1968 and revised in 1984. However, the Vertical Merger Guidelines have not been revised since 1984. Those Guidelines are now woefully out of date. They do not reflect current economic thinking about vertical mergers. Nor do they reflect current agency practice. Nor do they reflect the analytic approach taken in the 2010 Horizontal Merger Guidelines. As a result, practitioners and firms lack the benefits of up-to-date guidance from the U.S. enforcement agencies.

Publication Citation

Steven C. Salop & Daniel P. Culley, Revising the U.S. Vertical Merger Guidelines: Policy Issues and an Interim Guide for Practitioners, J. ANTITRUST ENFORCEMENT (forthcoming)