The 2023 Merger Guidelines and the Arc of Antitrust History

In 2023, the federal antitrust agencies rewrote the nation's flagship merger policy document, as part of a broader "Neo-Brandeisian" effort to bring about a deep reform of the antitrust system. The result—the 2023 Merger Guidelines—has been highly controversial: celebrated by some as a revolutionary advance, and criticized by others as a step back toward a benighted past. This article evaluates the 2023 guidance against the arc of antitrust's modern history. It argues that the new guidance breaks a long trend of migration from structure toward welfare as the primary orientation of merger enforcement, but that it does so cautiously, by achieving a fraught ambiguity between welfarist and nonwelfarist policies. In inviting both revolutionary and evolutionary readings, the agencies have sacrificed clarity and discouraged beneficial deals, but they have also deferred—at least for now—a sharp conflict between those who would preserve antitrust's governing paradigm and those who would remake it.