Key Differences and Requirements

Both the United States and the European Union require mandatory pre-merger notification for significant transactions, but their frameworks, criteria, and the role of subnational jurisdictions (states or member states) differ in several important ways.

United States

States are increasingly introducing broad pre-merger notification rules in addition to the federal Hart-Scott-Rodino (HSR) Act. Many state regimes mirror or modestly expand upon federal triggers and requirements:

Key Features

• Notification Triggers:
• Mergers reportable under the federal HSR Act are typically triggered by “size-of-transaction” and “size-of-person” tests, with thresholds adjusted annually.
• Recent state laws often use the same or similar triggers, and may include other local nexus criteria.
• Scope:
• Historically focused on healthcare, state notification regimes are expanding to cover all HSR-reportable transactions and, in some cases, transactions with a strong connection to the state.
• Fees & Timing:
• Filing fees are mandatory under the federal regime and typically scale with the size of the deal. The standard federal review period is 30 days and may be extended.
• At the state level, some states (such as Washington and Colorado) require notifications for deals with a significant local nexus, but do not charge a fee or impose a waiting period for their review.
• State Variation:
• States like Washington and Colorado require notification if:
• A party has its principal place of business in the state.
• A party has substantial annual sales in the state, or
• The transaction involves certain local industries (e.g., healthcare providers).
• These notifications are generally non-suspensory: filing does not bar deal closing and no regulatory approval or waiting period applies at the state level.

New York stands out in the evolving U.S. pre-merger notification landscape by pursuing a framework that goes significantly beyond both federal requirements and the standardized Uniform Antitrust Pre-Merger Notification Act (UAPNA) model seen in states like Washington and Colorado.

Expanded Compliance Scope:

• Firms doing any business in New York could be required to file pre-merger notifications for federally reportable transactions, regardless of their in-state sales volume or primary operations location. This would necessitate early identification and assessment of potential New York regulatory obligations in nationwide and cross-border transactions.
• Potential for Increased Scrutiny: The New York Attorney General would gain greater ability to review, challenge, or impose conditions on mergers with even minimal in-state business presence, independently of federal enforcement.

Legislative Uncertainty: While the Senate’s approval signals strong legislative intent, prior efforts at similar expansion have failed. The future of the bill remains uncertain pending Assembly and gubernatorial action.

European Union

At the EU level, the Merger Regulation (EUMR) offers a “one-stop-shop” for large, cross-border transactions. Below that threshold, each member state applies its own rules:

Key Features

• EU Dimension (“One-Stop-Shop”):
• Applies to mergers where:
• Combined global turnover >€5B, and
• Combined EU turnover >€250M for at least two parties, or
• Significant multi-jurisdictional turnover thresholds are met.
• Only the European Commission reviews such deals; no parallel filings at the national level are needed.
• Member State Regimes:
• All member states (except Luxembourg) have their own merger control rules for deals below the EU threshold.
• Jurisdictional thresholds are based on domestic turnover, sometimes with market share or transaction value criteria.
• Example:
• France: >€150M global and >€50M in France for each of two parties.
• Germany: >€500M global plus specific German thresholds.
• Italy: >€582M global and >€35M Italian turnover.
• Notification Impact:
• Suspensory: Deals cannot close until cleared by the relevant competition authority.
• Review assesses if the transaction would create/strengthen a dominant position or significantly impede competition.
• Filing Fees:
• Most EU countries now charge a filing fee for merger notifications at the national level.
• Notable exceptions (as of 2025): France, Italy, Finland, and Sweden.
• Referrals and Call-In Powers:
• National authorities can refer cases to the European Commission for review, and some states are increasing powers to review even deals that fall below formal thresholds.

Recent Developments

• EU Member States:
• Increasing use of “call-in” powers to examine mergers falling below standard notification thresholds (notably in France, Italy, and Germany).
• Rising prevalence of member state filing fees.
• United States:
• States leveraging independent notification rules for earlier and parallel enforcement actions, especially in sectors of local policy interest.
• State filing regimes may be non-suspensory and fee-free, reducing friction for deal closing, but increasing compliance considerations.

Conclusion

Both the U.S. and EU systems are evolving toward greater scrutiny at the state/member state level. In the EU, large deals benefit from a coordinated, central review, while local deals can face diverse national requirements that are always suspensory and now often subject to significant filing fees. In the U.S., federal rules remain paramount, but state-level notifications are proliferating—some are non-suspensory and fee-free, but compliance obligations are rising, particularly for transactions with local nexus.

U.S. and EU Merger Control Policy

The paradox at the heart of current transatlantic merger control debates

While there is a narrative of increased convergence between US and EU approaches—driven by shared goals like supporting domestic champions and fostering innovation—this is unfolding against a backdrop of revived protectionism and industrial policy on both sides of the Atlantic. The reality is that convergence often means both sides are more open to deals that serve their own strategic interests, rather than a blanket shift toward a more deal-friendly environment for all transactions.

Important differences remain. Despite some harmonization in process and rhetoric, US and EU merger control regimes are still shaped by distinct legal cultures, enforcement philosophies, and political priorities and some skepticism about non-EU attorneys’ understanding of EU law is not entirely unfounded. For example, the EU continues to emphasize market integration and state aid control, while the US approach remains more pragmatic and case-specific.

The Draghi Report has certainly reignited debate in Brussels about recalibrating EU competition policy to prioritize economic growth, innovation, and the creation of European champions, especially in tech and strategic sectors. However, many foundational aspects of EU merger control remain unchanged, and political resistance to major reforms is still strong.

The EU’s commitment to balancing market integration with sovereignty remains highly relevant. Despite new reports and shifting rhetoric, these core distinctions continue to shape merger policy and enforcement outcomes. The complexity and specificity of EU merger control—especially regarding the scope of antitrust intervention and the role of industrial policy—make EU attorneys' expertise indispensable.  CILC’s model—anchored by US/EU-qualified attorneys—offers clients a strategic advantage in navigating the increasingly complex and convergent landscape of transatlantic merger control, ensuring expert, efficient, and privileged legal support throughout the process.

Practical Benefits for Clients

• One-Stop Service: Clients benefit from a single point of contact who understands both US and EU regulatory expectations, reducing the risk of miscommunication or strategic misalignment.
• Enhanced Privilege Protection: CILC’s integrated model helps ensure attorney-client privilege is maintained across borders, a challenge in traditional multi-firm setups.
• Informed Advocacy: CILC's attorneys can advocate effectively before both US and EU regulators, leveraging their direct experience and relationships with authorities in both regions.
• Efficient, Predictable Outcomes: The combination of comparative legal analysis, regulatory experience, and technology-driven processes leads to more predictable, business-friendly outcomes for complex, cross-border transactions and investigations