DOJ/FTC issued the final version of the Merger Guidelines on December 18, 2023. While some language has been clarified or removed since the July 2023 draft, much remains largely unchanged. The Merger Guidelines reflect the current administration and agencies’ continued skepticism of merger activity and will likely result in more frequent and thorough investigations of transactions, more time needed for regulatory review, and more mergers likely to be scrutinized as presumptively unlawful.