This article traces the evolution of federal merger policy. It documents how merger enforcement originally was largely based upon very strong structural presumptions. These presumptions gradually eroded and other factors became more and more important in enforcement decisions. Today meger enforcement essentially consists of structural safe harbors and a full rule of reason analysis for any merger not within these safe harbors.
From Surrogates to Stories: The Evolution of Federal Merger Policy, 11 Antitrust 5 (1997)