Merger Breakups

One of today’s most pressing antitrust questions is how antitrust should address the conduct of dominant technology companies. Once considered untouchable by antitrust law, these technology behemoths are now the subject of growing calls for antitrust breakup, including through actions by the federal antitrust agencies to challenge and unwind key mergers in the technology space. But nearly every one of the technology mergers identified for ex post challenge and breakup was previously reviewed and cleared by the antitrust agencies pursuant to the existing federal merger review scheme, even after a lengthy investigation in some instances. The calls for the antitrust breakup of these identified technology mergers therefore implicate a much more fundamental antitrust question: should the antitrust agencies more readily challenge mergers that they themselves previously reviewed and cleared pursuant to the existing federal merger review scheme? This Article offers a qualified affirmative response to that question. The antitrust agencies should increase the extent of their challenges to previously reviewed and cleared mergers but should do so in a principled way that respects the significant mitigating factors associated with an expansion in such ex post merger challenges. By conducting that principled analysis, this Article identifies important limiting conditions on the expansion of agency challenges to previously reviewed and cleared mergers