Today, AAI released the new white paper: What Does the Billion-Dollar Deal Mean for Stronger Merger Enforcement? The Biden Administration’s antitrust chiefs have committed to invigorating merger enforcement. The white paper makes a strong case for why the remarkable growth in the size of mergers over time should be a major factor in the agencies’ calculus for managing risk and allocating scarce resources as they develop and implement a program of more vigorous enforcement. The white paper explains why the billion-dollar merger plays a unique, major role in both early- and late-stage enforcement. Billion-dollar deals feature prominently in the universe of mergers that the agencies challenge, supporting the notion that large mergers generally pose a greater likelihood of raising competitive concerns. Moreover, billion-dollar transactions account for an outsized proportion of illegal mergers that are settled, versus resolved through other means such as forced abandonments, restructurings, and injunctions. The white paper examines the implications of these, and other findings, for agency decision-making, with major takeaways and recommendations for addressing the impact of the billion-dollar merger on a program of stronger merger enforcement.