Antitrust and M&A: Is Everything Old New Again?

With every change in administration, businesses and practitioners wonder what the new administration will mean for antitrust enforcement in the United States. Speculation was at fever pitch four years ago, after Democratic officials expressed the view that antitrust enforcement had languished and needed revival. President Biden’s antitrust triumvirate of Federal Trade Commission (FTC) Chair Lina Khan, Department of Justice (DOJ) Antitrust Division head Jonathan Kanter and White House Technology and Competition Policy Advisor Tim Wu promptly initiated aggressive policy proposals and enforcement steps. In the realm of M&A, a general sense that mergers were inherently “bad” seemed to prevail in the rhetoric of some antitrust officials.

What, then, should we expect for the antitrust review of mergers in the second Trump Administration? Will FTC and DOJ return to the relatively traditional enforcement approach of the first Trump Administration, or have the enforcement winds changed? To answer these questions, it is useful to consider (i) what the data tells us about enforcement changes during the first Trump and the Biden administrations and (ii) how personnel decisions and expected administration priorities give initial insight into probable initiatives over the next four years.

A. Looking Back: How Did Biden-Era M&A Enforcement Compare With Trump 1.0?

Although the new administration is Republican, a return to Bush-era enforcement—much less Reagan-era laissez-faire—is unlikely. Even a quick look at antitrust activity in the first Trump Administration reveals significant enforcement, including against mergers.¹ For example, DOJ sued to block AT&T’s proposed acquisition of Time Warner based on concerns that it might foreclose access to Time Warner content—an ultimately unsuccessful “vertical” merger challenge.² Other prominent litigated mergers included Visa/Plaid,³ Peabody/Arch Coal,⁴ Evonik/PeroxyChem,⁵ Altria/JUUL⁶ and Axon/VieVu.⁷

By some counts, the first Trump Administration initiated more significant merger investigations than the Biden Administration, although comparisons of absolute enforcement activity are inherently fraught because of the lower level of M&A activity in recent years. A potentially more revealing statistic is the percentage of Hart‑Scott‑Rodino Act (HSR) reportable transactions that received “second requests” from DOJ or FTC, because a higher percentage of second requests—which initiate in-depth merger investigations, typically after one to two months of review—could indicate greater sensitivity to potential antitrust concerns. On this score, the data is unremarkable. Taking the government’s fiscal year 2023 as an example, 37 of the 1,805 HSR filings (or roughly 2%) triggered second requests.⁸ In 2022, second requests similarly accounted for approximately 1.5% of HSR filings.⁹ This is consistent with the long-standing trend that about 2% of HSR filings result in in-depth reviews.¹⁰

Comparing M&A enforcement data in the first Trump and the Biden administrations nevertheless reveals two notable differences. First, the number of mergers ending in negotiated settlements between the parties and the antitrust agencies (typically in the form of divestiture remedies) declined dramatically during the Biden years, both in absolute terms and as a percentage of total cases.¹¹ This is consistent with statements from antitrust agency leaders early in the Biden Administration expressing concerns that divestitures often were ineffective because they did not replace the competition lost as a result of a merger.¹²

The second insight, a corollary of the first, is that abandoned transactions increased during the Biden Administration. Westlaw Practical Law counts 22 abandoned transactions between 2016 and 2020 in significant antitrust investigations, or roughly 18% of recorded matters. In the 2021–2024 period, 29 transactions were abandoned under these circumstances—a remarkable 35% of recorded deals that received significant scrutiny. Here again, the data is consistent both with the Biden-era agencies’ greater reluctance to accept settlements and with greater reservations about M&A’s impact on the American economy in general.

B. Looking Ahead: Likely Changes and Initiatives

Personnel decisions for agency leadership and known policy preferences suggest that it is reasonable to anticipate several changes in the second Trump Administration.

• Less Hostility Toward Mergers. Antitrust agency officials in the Biden Administration made clear that they were looking for ways to bring cases, including those based on more novel theories. That skeptical, anti-merger sentiment will likely change in the second Trump Administration. However, merger enforcement will not disappear. Many on the conservative-leaning side of antitrust policy circles are equally committed to enforcement, including in horizontal mergers and against large technology companies.
• Return of Negotiated Settlements. In contrast to the Biden era’s skepticism of merger remedies, the first Trump Administration accepted divestiture remedies even in high-profile mergers such as CVS/Aetna¹³ and Sprint/T-Mobile.¹⁴ There is little indication that this approach has fallen out of favor among the likely Republican agency leadership—indeed, one of the two Republican FTC commissioners recently said that the antitrust agencies should be “pragmatic” with remedies in mergers.¹⁵ We therefore will likely see a rise in the number of negotiated consent decrees in the new administration.
• Restoration of Early Termination. In 2021, the antitrust agencies abandoned early terminations of the HSR waiting period, meaning that parties had to wait at least 30 days to close a transaction, even if the agencies decided not to investigate. The FTC announced that it will lift this suspension following the final revised HSR rule coming into effect, likely in early 2025.¹⁶
• Revisions to the 2023 Merger Guidelines. The 2023 Merger Guidelines may be revised or rescinded under the new administration. These guidelines were a significant departure from prior guidelines, lowering concentration thresholds required for transactions to trigger a presumption of competitive harm and signaling a greater focus on serial acquisitions, potential competition and labor markets, among other concepts. Republican FTC Commissioner Melissa Holyoak has said that she would “strongly consider” revising the guidelines,¹⁷ while Chair Andrew Ferguson has said that there were aspects of the guidelines he would be open to reforming.¹⁸
• Abandonment of the FTC Non-Compete Ban. The FTC’s non-compete ban enacted in April 2024 is unpopular with many Republicans. The rule would have become effective in September 2024 but was challenged in multiple district courts. A Texas court enjoined the ban nationwide, and an appeal is pending in the 5th US Circuit Court of Appeals. While this could play out in several ways, it seems unlikely that the rule will survive. Chair Ferguson dissented from issuing the rule, stating that it was unlawful and outside the FTC’s authority.¹⁹
• Sector-Specific Enforcement. An open question remains as to whether the new administration will take a more hands-off antitrust approach to M&A activity in specific sectors. High on this list is traditional (fossil fuel) energy, which President Trump has long championed. Nevertheless, it may be premature to expect laissez-faire antitrust reviews of energy transactions. Some energy M&A transactions, even those that involve large players, occur in relatively unconcentrated markets and therefore often do not raise concern.²⁰ And in more concentrated segments, it is not clear that the new administration’s policy support for fossil fuels will translate into support for additional M&A. For example, the first Trump Administration challenged the combination of Peabody and Arch Coal on the basis that it eliminated competition between the two largest coal miners in the Southern Powder River Basin in northeastern Wyoming.²¹ In addition, to the extent fossil fuel energy M&A has implications for consumers—such as by affecting gas prices—the new administration likely would not want to be seen as tolerating these impacts.

C. Conclusion

Some antitrust enforcement questions remain as we enter the second Trump Administration. Nevertheless, US antitrust agencies are expected to retreat from the Biden-era envelope-pushing merger enforcement, and parties to reportable mergers can anticipate the return of negotiated remedies and early termination. Enforcement into traditional horizontal and vertical concerns will likely remain robust, as will scrutiny of large technology companies.