“Most mergers in industries with only a handful of competitors are anticompetitive, so why don’t we block them?” asks Neal F. Finnegan Distinguished Professor of Economics John Kwoka. “The fix is to use a structural presumption to lower the burden for regulators,” he argues, stating that “a well-designed merger enforcement policy should focus on mergers with the greatest likelihood of anticompetitive outcomes,” which has not recently been true of United States policy.