Merger Control Law Guide

Practical tips for managing multiple regulatory reviews of a cross-border transaction

We are delighted to introduce this guide to merger control regimes around the world. Our warmest thanks go to our international community of eminent antitrust practitioners for sharing their expertise and insights.

We live in turbulent times from a geopolitical perspective. The old conventions around “lead” regulators, comity between jurisdictions and nexus do not apply in the same way. With the digital economy challenging old approaches to jurisdictional thresholds based on turnover and local presence, many jurisdictions have sought to include discretionary rules around call-in of non-notified deals.

While the focus of this publication is merger control, it is the norm for a transaction to be reviewed under multiple regulatory regimes spanning merger control, foreign direct investment (FDI) screening, and the EU’s Foreign Subsidies Regulation (FSR) which each assess acquisitions and investments through a different lens, apply different legal tests, and run on different clocks.

The most useful introduction to this collection of country-specific chapters might therefore be to put them into their practical context. Accordingly, we have highlighted the main challenges in successfully securing multijurisdictional clearances for a cross-border deal and offered practical suggestions to address them to secure the optimum outcome for the merging parties.

Multiple legal frameworks – merger control and beyond

Around the world, merger control is relatively consistent in its underlying objectives, focused on whether the deal will substantially reduce competition, often with a focus on potential harm to consumers. Increasingly and most recently in the European Union, wider deal impacts are being factored in, including supply chain resilience or the impact of a transaction on labour markets. FDI screening asks whether the deal threatens national security, public order or, as is increasingly being openly recognised, economic security. The EU’s FSR seeks to prevent non-EU government subsidies and wider government “contributions” from distorting competition in EU markets and is more or less unique globally as a mechanism for reviewing M&A. Each regime has its own notification thresholds, information requirements, timeline and decision-makers.

In Europe, for example, the EU Merger Regulation (EUMR) offers a “one-stop-shop”, removing the need to consider Member State merger control regimes (and potentially a further three European Free Trade Area regimes). However, each Member State operates its own FDI regime, with no one-stop-shop and the FSR may also apply.

The revised EU FDI Screening Regulation, which will come into full effect on 17 January 2028, will expand cooperation and harmonise Member State FDI screening obligations but will not create a centralised regime. Moreover, the EU’s proposed Industrial Accelerator Act would introduce mandatory requirements for certain large ex-EU investments in designated strategic sectors. This legislation is controversial (and currently expected to fall mainly on Chinese investors) but is, at present, planned to be in place by the end of 2026.

Parties therefore frequently face parallel filings under the EU Merger Regulation, the FSR, and multiple national foreign direct investment screening regimes for a single deal, in addition to any merger control or FDI filings required outside Europe.

Managing this challenge:

• Ensure there is a central coordinating team overseeing the identification and coordination of multi-jurisdictional filing requirements, and ensuring the filing strategy is consistent with deal objectives and timelines.
• Proactively engage with authorities on substance and timing, in order to manage parallel reviews and encourage consistency.

Aligning timelines

Each merger regime runs on its own procedural clock. The EUMR and FSR have broadly similar timetables and are both administered by different teams within the Commission, but in practice the two often do not run in parallel, particularly if there are significant issues under one regime but not the other. National FDI screening timelines vary considerably and are usually administered by the government, not by an independent agency (as is usually the case for merger control).

Managing this challenge:

• Ensure that the contractual longstop date reflects the projected time required to secure all clearances, including filing preparation, pre-notification periods (if applicable), formal review timeframes, potential for the statutory clock being stopped and the negotiation of any remedies. A long-stop date that is too tight can force premature concessions or cause the deal to fail.
• Consider filing in parallel where possible, but think carefully about sequencing. Securing clearance first in an uncontroversial jurisdiction can create useful momentum; conversely, if a Phase 2 investigation is likely in the EU, it may be prudent to delay certain national filings until the Commission’s concerns are better understood, since the scope of any EU remedy may shape the competitive analysis elsewhere.
• Clearances in certain jurisdictions are only valid for a specified period, meaning that parties will want to avoid having to re-file or obtain a fresh clearance if the transaction has not closed within that period (e.g., due to in-depth reviews elsewhere).
• Pre-notification engagement can be used to refine the issues to be considered during the formal review period and can, where needed, be used to get remedy discussions underway “off the clock”.

Encouraging coordination between authorities

Merger control authorities have well-established channels for cooperation, regularly exchanging information and views on global transactions, subject to appropriate waivers from the parties. There is much less coordination between merger control authorities and FDI screening bodies, even within the same country, and very limited transparency about coordination between FDI agencies. The FSR is enforced by the European Commission, which also handles EU merger control, but the two reviews are conducted by separate teams.

Managing this challenge:

• To support alignment between agencies, consider granting confidentiality waivers early to allow them to share information with each other.
• Ensure that the central coordinating team is continually updated with developments in each review. Where a remedy is being discussed with one authority, consider whether it could affect the analysis in another regime.
• Recognise that FDI screening bodies are not accustomed to structured multilateral cooperation. Where parallel FDI filings are required in several Member States, the parties’ advisers may need to serve as a de facto coordination mechanism, proactively flagging to each authority what conditions others are considering, to avoid contradictory requirements emerging late in the process.
• Where the Commission’s EUMR and FSR teams are both reviewing the same deal, engage with both teams early and seek to align the timing of pre-notification discussions.

Telling a consistent story

Descriptions of deal rationale, relevant markets, the competitive landscape, and the parties’ activities must be consistent across all filings, although different aspects will be emphasised in different contexts. Cooperation between agencies makes consistency all the more important.

Managing this challenge:

• A common set of core facts should form the basis for all filings, tailored for each regime, with the central coordinating team acting as gatekeeper, reviewing all drafts for consistency.
• Pay particular attention to internal documents (board papers, strategy presentations, integration plans) disclosed through parallel document production obligations. Authorities increasingly cross-reference internal documents cited in one jurisdiction against submissions made elsewhere. A document relied on in one filing but downplayed or omitted in another can damage credibility.
• Where the relevant market definition is different between jurisdictions (e.g., national markets within the EU) ensure the reasoning is internally coherent and clearly articulated. Market definitions may legitimately differ due to factual differences or different case law precedent, but authorities will scrutinise whether differing definitions are being deployed opportunistically to serve the parties’ interests.
• Tools such as GenAI can assist in scanning for inconsistency or in mapping factual differences between filings in different jurisdictions and across regimes.

Aligning remedies

Where a transaction raises concerns under more than one regime, remedies may be needed in different jurisdictions to secure clearance. In certain cases, a single divestiture remedy may address concerns across multiple jurisdictions but parties also often need to address jurisdiction-specific concerns.

Remedies in FDI are driven by specific national security concerns and may be less predictable where they reflect the politics of the government in question. The conditions under the EU’s proposed Industrial Accelerator Act may offer no flexibility. In the limited FSR remedies cases to date, the Commission has been more flexible than it has traditionally been for merger control remedies, accepting behavioural commitments including counterbalancing remedies to compensate for harm, rather than directly remedying it.

Alignment across regimes can be correspondingly complex.

Managing this challenge:

• Think about remedies holistically from the outset. Where a structural remedy is likely in one jurisdiction, model its impact on the competitive assessment in other jurisdictions.
• A divestiture that satisfies one agency may strengthen a competitor that is the subject of concern in another market, or remove assets that an FDI authority regarded as critical to its national security assessment. These second-order effects should be monitored.
• Consider whether an up-front buyer strategy can accelerate clearance across multiple jurisdictions simultaneously, since it removes execution risk and allows parallel remedy discussions to converge around a single, concrete proposal.
• Be aware that behavioural remedies accepted in one regime (such as firewalling arrangements under FDI) may be viewed by a merger control authority as insufficient to address a structural competition concern.
• Ensure that, individually and in aggregate, remedies do not undermine the deal rationale or its financing.
• Engage in early, informal discussions with key authorities about the acceptability and shape of potential remedies before making formal offers.

Conclusion

Complexity in the regulatory landscape is a defining feature of transaction planning today. The interaction between merger control, foreign direct investment screening, and the FSR (with the possible future addition of the EU’s Industrial Accelerator Act) means that deal teams must think across regimes and borders from day one. Managing multiple regulatory clearances for a cross-border transaction requires upfront strategic planning and disciplined communication of a consistent narrative, supported by a coordinating team to maintain consistency while reflecting local differences, all the while problem-solving through the current tectonic shifts in the macroeconomy.

Our hope is that this collaborative work will play its part in enabling dealmakers to successfully map the merger control landscape and anticipate challenges before they arise: a true “think global, act local” mindset!