US antitrust enforcement has intensified markedly. Both the Department of Justice Antitrust Division and the Federal Trade Commission have shifted to a more aggressive posture. expanding the categories of conduct they investigate. Widening merger notification requirements. Additionally, pursuing criminal cartel prosecutions with renewed vigour. International companies with US operations or US-facing commercial arrangements face direct exposure to these enforcement actions.
The US competition authority regime is administered by two federal agencies – the Department of Justice and the Federal Trade Commission – operating under federal antitrust legislation. Updated merger notification thresholds effective early 2025 require parties to file when transaction values or party size crosses revised monetary benchmarks. International businesses holding market dominance in sectors including technology, pharmaceuticals, agriculture, and financial services are among the primary targets of current enforcement priorities.
This alert explains which businesses are most exposed, what the current compliance deadlines require, and what steps international companies should take immediately.
Who is affected and what has changed
The enforcement shift is broad, but certain business categories face the most immediate risk. Technology platforms, pharmaceutical distributors, defence contractors, and financial intermediaries are under active scrutiny. Any company – including a foreign entity operating through a Delaware LLC (a limited liability company incorporated under Delaware corporate law) or similar US vehicle – falls within the jurisdictional reach of federal antitrust legislation.
The key regulatory developments in effect as of early 2025 include the following:
- Revised merger notification thresholds under the Hart-Scott-Rodino (HSR) premerger notification rules, adjusted annually and materially increased, now capture a wider set of transactions that previously fell below filing requirements.
- Expanded HSR filing requirements for transactions involving minority stakes, non-compete arrangements, and certain cross-border deals – including acquisitions by foreign acquirers of US targets.
- Renewed criminal prosecution of cartel conduct, with the DOJ pursuing price-fixing and bid-rigging cases across construction, staffing, and agriculture sectors.
- The FTC's updated guidance on unfair methods of competition, broadening the categories of conduct reviewable beyond traditional antitrust analysis.
Foreign businesses often underestimate their exposure. A company without a physical US presence can still trigger HSR notification obligations if the transaction meets the applicable size-of-transaction and size-of-person thresholds. The effects doctrine – a well-established principle of US federal antitrust law – means that conduct occurring entirely outside the United States can fall within the jurisdiction of a US District Court if it produces anticompetitive effects in US markets.
Companies operating leniency programme strategies – that is, cooperating with authorities in exchange for reduced penalties – must also reassess those strategies under current DOJ guidance. The leniency programme remains available, but its terms and conditions have been refined. Self-disclosure decisions must be made with precise legal advice and within narrow timeframes.
For companies involved in SEC-regulated industries, competition authority scrutiny may intersect with securities disclosure obligations. Enforcement actions by the FTC or DOJ can trigger material event disclosure requirements under federal securities legislation. This dual exposure – competition and securities – is a non-obvious risk that international in-house teams frequently miss.
To receive an expert assessment of your company's exposure under current US antitrust enforcement, contact us at info@ferrazwhitmore.com.
Immediate actions for international companies
The compliance window for several of these changes has already opened. Companies that have not yet reviewed their US-facing commercial arrangements against the updated rules risk enforcement action, civil penalties, and – in cartel matters – criminal liability. The following actions are required without delay.
Review transaction pipelines against revised HSR thresholds. Any M&A or investment transaction involving a US nexus should be re-screened. The revised thresholds apply to transactions signed after the effective date of the adjustment. Engage a lawyer in the United States – or international counsel with US competition expertise – to confirm whether notification is required before closing.
Audit commercial agreements for cartel risk. Price-fixing, market allocation, and bid-rigging arrangements – even informal ones – constitute per se violations of federal antitrust legislation. All active distribution, supply, and consortium agreements should be reviewed. This is particularly urgent for companies participating in industry associations, where competitor communications can inadvertently cross the cartel threshold.
Assess market dominance positions in US sectors. The FTC's expanded use of unfair competition authority means that conduct by dominant firms. including unilateral refusals to deal. Exclusive arrangements. Additionally, platform self-preferencing. is subject to challenge even where it does not meet the traditional predatory pricing standard. Companies with strong US market positions should document their competitive rationale for key commercial practices.
Prepare a leniency programme response protocol. If your company has knowledge of potential cartel conduct involving US markets, the decision to self-report to the DOJ must be made quickly. The leniency programme grants the first qualifying applicant immunity from criminal prosecution. Delays eliminate this option entirely.
Consider AAA arbitration and JAMS clauses in US contracts. Where commercial disputes with US counterparties may involve competition law claims. Dispute resolution clauses specifying AAA arbitration (American Arbitration Association) or JAMS (Judicial Arbitration and Mediation Services) can limit exposure to US District Court litigation and its associated discovery burdens. Review and update dispute resolution provisions in key contracts accordingly.
For international companies with cross-border competition issues, our related alert on competition enforcement in Brazil provides a comparative perspective on enforcement trends across the Americas region.
Companies facing active investigations or contemplating leniency applications should also review our full service coverage of competition law in the United States. This details the procedural steps and strategic options available at each stage of an enforcement proceeding. Where competition authority actions give rise to private litigation or shareholder claims, our team's experience in corporate disputes in the United States provides integrated support across both tracks.
About Ferraz & Whitmore
Ferraz & Whitmore is an international law firm based in Lisbon, advising business clients across 46 jurisdictions. Our competition law practice supports international companies facing US antitrust enforcement, merger notification obligations, and cartel investigations. We combine English common law expertise with deep familiarity with civil law systems across Europe and the Americas – providing integrated advice for businesses that operate across multiple legal regimes. Our attorneys have advised on competition matters before federal authorities and in proceedings under both AAA arbitration and JAMS rules. As a law firm advising international clients on US competition law, we provide clear, actionable counsel at each stage – from pre-merger screening through to leniency applications and follow-on litigation. For a preliminary review of your company's competition exposure in the United States, contact us at info@ferrazwhitmore.com.
Disclaimer: This publication is provided for informational purposes only and does not constitute legal advice. The information herein should not be relied upon as a substitute for professional legal counsel tailored to your specific circumstances. Ferraz & Whitmore assumes no liability for actions taken or not taken based on the contents of this material. For advice regarding your particular situation, please contact info@ferrazwhitmore.com.