Orley Ashenfelter, Daniel Hosken, Matthew Weinberg, Apr 30, 2009
The challenge of effective merger enforcement is tremendous. U.S. antitrust agencies must, by statute, quickly forecast the competitive effects of mergers that occur in virtually every sector of the economy to determine if mergers can proceed. Surprisingly, given the complexity of the regulators task, there is remarkably little empirical evidence on the effects of mergers to guide regulators. This paper describes the need for retrospective analysis of past mergers in building an empirical basis for antitrust enforcement, and provides guidance on the key measurement issues researchers confront in estimating the price effects of mergers. We also describe how evidence from merger retrospectives can be used to evaluate the economic models that predict the competitive effects of mergers.
Featured News
Beumer Challenges EU Decision on Vanderlande-Siemens Merger Review
Jul 26, 2026 by
CPI
China Fines Trip.com US$765 Million in Major Antitrust Enforcement Action
Jul 26, 2026 by
CPI
House Judiciary Panel Launches Antitrust Inquiry Into Compass and MRED
Jul 26, 2026 by
CPI
Paramount Delays Warner Bros. Discovery Merger Until Antitrust Case Moves Forward
Jul 26, 2026 by
CPI
Judge Pushes Elite College Financial Aid Antitrust Trial Toward Thanksgiving Finish
Jul 23, 2026 by
CPI
Antitrust Mix by CPI
Antitrust Chronicle® – Antitrust Compliance
Jul 20, 2026 by
CPI
Your Antitrust Compliance Program: A Strong Voice in Your Defense
Jul 20, 2026 by
Joe Murphy
Antitrust Compliance for the AI Pricing Era
Jul 20, 2026 by
Alejandra Uria & Andre Geverola
Race to Report: Antitrust Leniency in the Whistleblower Era
Jul 20, 2026 by
Brian R. Faerstein & Nicole H. Sprinzen
Antitrust-By-Design: Competition Compliance in Digital Markets
Jul 20, 2026 by
Marcos Drummond Malvar, Gabriela Costa Carvalho Forsman & Luciana Mendes