Geographic Market Definition in the Merger Guidelines: A Retrospective Analysis

Since the initial Merger Guidelines in 1968, the Department of Justice and Federal Trade Commission have revised their merger enforcement screen over the course of six versions. This article examines the evolution of the geographic market component of the Guidelines and the economic implications of changing standards of market delineation on merger enforcement. Using an illustration from the beer industry, we chronicle the development of geographic market definition and its varying effects on merger enforcement over the past 50 years.