Merger Guidelines and the Limits of Our Understanding

The merger guidelines have evolved from a structural standard for determining the legality of mergers to an open-ended evaluation that attempts to predict whether some specific harm to competition is likely. These efforts have been unsuccessful; moreover, mergers generally contribute no positive economic gain. Blocking mergers that may have little or no adverse effect on competition will not cause significant economic harm; but the failure to interdict mergers that do cause harm imposes significant costs on the economy. Merger enforcement policy should return to the structural method of the 1968 Guidelines as well as impose stricter structural standards.