The intellectual and political center of gravity in United States antitrust enforcement has shifted, and the pattern of cases that the federal agencies are now choosing to bring looks different from the pattern that defined the prior decade. The most visible cases of the recent past — the structural challenges to large technology platforms, the merger reviews that produced novel theories of harm in adjacent and conglomerate combinations, the enforcement actions premised on labor-market monopsony — have not disappeared, but they no longer dominate the docket in the same way. The new pattern is more difficult to summarize in a single phrase, and that difficulty is itself part of the story.

One element of the shift is a narrower posture toward merger review. The agencies remain active in screening transactions, but the proportion of deals that draw a second request, much less an outright challenge, has declined from the recent peak. The screening criteria that emerged during the prior administration have been quietly revised, and the practical effect is that more transactions are clearing on a shorter timeline than dealmakers had come to expect. The change has not yet been formalized in a new set of merger guidelines, but practitioners report that the working assumptions inside the agencies have moved.

A second element is a renewed focus on conduct cases in sectors that had received less attention in the prior cycle. Healthcare consolidation, particularly at the level of physician practices and outpatient services, has drawn more scrutiny, with investigations into pricing behavior, network exclusivity, and the integration of upstream suppliers with downstream providers. The agriculture sector, where concentration concerns have been a feature of the political discussion for years without producing many cases, has begun to see more activity. The pattern suggests an enforcement posture that is more retail in its focus and more attentive to the price effects on identifiable consumer groups than the prior administration’s more structural approach.

A third element is the changing posture of the courts. Several of the more ambitious theories of harm that the agencies advanced in the previous cycle have not fared well at trial or on appeal, and the cumulative effect has been to narrow the legal space within which novel cases can be expected to succeed. The agencies’ litigation strategy has adjusted in response, with a higher proportion of cases now built around the more conventional showings of market definition and competitive effect that courts have proven willing to credit. The downside for the agencies is that the cases they bring are less likely to extend the doctrine in directions that would constrain future conduct, but the upside is a higher win rate.

State attorneys general have moved into some of the space that the federal agencies have vacated. A number of states have built up substantial in-house antitrust capacity over the past several years, and the cases they are now bringing — particularly in healthcare, agriculture, and platform-adjacent markets — have begun to set precedents at the state level that may eventually shape federal doctrine. The coordination among state attorneys general has also tightened, with multi-state actions becoming the default rather than the exception, and the result is an enforcement landscape that is more polycentric than at any recent point.

The international dimension has added complexity that did not exist in earlier eras. European, British, and several Asian competition authorities are pursuing their own enforcement agendas, and the largest transactions now routinely face parallel reviews in multiple jurisdictions whose substantive standards do not always align. The United States agencies have begun to coordinate more openly with their international counterparts on the largest cases, but the coordination is partial, and the result is a regulatory environment in which transactions can clear in one jurisdiction and be blocked in another, with consequences for how dealmakers structure transactions from the outset.

The economic literature on which enforcement decisions rest has continued to evolve in directions that complicate the political debate. Empirical work on the effects of mergers, on the relationship between concentration and prices, and on the labor-market consequences of consolidation has produced a more nuanced picture than the simpler narratives on either side of the debate suggest. The agencies’ staff economists are integrating that work into their case selection more visibly than they did in earlier cycles, and the practical effect is a more selective enforcement posture that focuses agency resources where the empirical case is strongest.

The cumulative effect is an antitrust environment that is more active than the libertarian critique suggests but less doctrinally adventurous than the structuralist hopes implied. Dealmakers, corporate counsel, and the boards that approve transactions are operating with a more predictable set of expectations than they had during the recent peak of activity, and that predictability is itself a contribution to deal flow. Whether the new equilibrium endures will depend on the cases that are now in the pipeline, on the courts that will decide them, and on the political environment that will inevitably reshape the agencies’ priorities again at the next transition.