By Ann Bradford, Adam Chilton & Filippo Maria Lancieri, Oxford Business Law Blog
A group of scholars primarily associated with the University of Chicago began to challenge many of the fundamental tenets of US antitrust law in the 1950s. This movement—which became known as the Chicago School of Antitrust Analysis—profoundly altered the course of American antitrust scholarship, regulation, and enforcement. Antitrust law became increasingly informed by economic theories with formalistic per se rules giving way to a case-by-case assessment of the economic effects of firm conduct.
Many previously established antitrust doctrines—from the challenging of vertical mergers to the per se treatment of several forms of unilateral conduct by monopolies—were gradually reversed as a result. Although antitrust scholars may disagree on the appropriateness of the Chicago School ideas, few would question the profound influence those ideas have had on US antitrust policy.