When two companies combine—through a merger, an acquisition, or the creation of a joint venture—the deal can reshape markets overnight. Prices, innovation, consumer choice, and supplier relationships may all shift. That’s why the European Union reviews certain transactions before they close, to make sure competition remains fair and consumers are protected.
EU merger control is often described as “procedural,” but in real life it’s operational: it affects signing and closing dates, information requests, integration planning, financing conditions, and even how teams communicate. Understanding the responsibilities and the timeline is one of the simplest ways to reduce deal risk.
What EU merger scrutiny is (and isn’t)
EU merger scrutiny is primarily governed by the EU Merger Regulation (EUMR) and enforced by the European Commission’s Directorate-General for Competition (DG COMP). If a deal meets the jurisdictional thresholds, the Commission can require the parties to notify the transaction and wait for approval before closing.
This process is not a general “business approval.” The Commission does not assess whether a deal is strategically smart or financially sound. Instead, it evaluates whether the transaction would significantly reduce competition—often by creating or strengthening market power, reducing rivalry, or making coordination between competitors easier.
When a deal must be notified to the European Commission
Not every transaction triggers EU-level review. The Commission generally reviews deals that have an “EU dimension,” meaning the parties’ turnover crosses specific thresholds and the deal is large enough to potentially affect markets across multiple Member States.
In practical terms, the key question is: do the parties’ revenues meet the EUMR turnover thresholds? If yes, EU notification may be mandatory and exclusive (meaning national authorities typically step back, with some exceptions). If no, the deal may still be reviewable by one or more national competition authorities, depending on local rules.
Because turnover calculations and group structure can get complex, parties usually treat jurisdiction as a legal workstream early in the deal process, not as a last-minute compliance task.
The standstill obligation: why timing matters immediately
Once a deal is notifiable under the EUMR, the parties must respect the “standstill obligation” (often called the suspension obligation). This means they cannot close the transaction before clearance.
This affects more than just the legal closing. “Gun-jumping” risk can arise if the buyer effectively takes control early—through decision rights, operational influence, sensitive information sharing, or premature integration. The safest approach is to plan clean team protocols, information barriers, and integration steps in a way that preserves independence until approval.
Who is responsible for what
EU merger review is a shared effort between the merging parties and the Commission, but the work burden sits heavily with the companies. Responsibilities typically break down like this:
- The notifying parties prepare the filing, gather data, respond to information requests, and propose remedies if needed.
- DG COMP runs the investigation, tests evidence with market participants, and decides whether to clear, conditionally clear, or open an in-depth review.
- National competition authorities (NCAs) may provide input, receive referrals, or handle parallel review if the deal falls outside EU jurisdiction.
- Third parties (competitors, customers, suppliers) often play a practical role because the Commission contacts them for market feedback.
Inside the companies, responsibility usually spans legal, finance, sales, product, procurement, and data teams. One common cause of delay is underestimating how much time it takes to compile reliable market-share estimates, customer lists, internal strategy documents, and pipeline information.
The EU merger review timeline (high level)
While every transaction differs, EU merger scrutiny follows a predictable structure:
- Pre-notification (informal, but often critical for timing)
- Formal notification (submission of the filing)
- Phase I review (initial review period)
- Phase II review (in-depth investigation, only for problematic cases)
- Remedies and commitments (if required)
- Clearance decision and closing (once approval is obtained)
The “clock” mostly runs only after formal notification is accepted as complete, but the real calendar risk often comes from pre-notification and information gathering.
Pre-notification: the hidden timeline driver
Pre-notification is not formally required by the regulation in every case, but in practice it is common—especially for deals involving overlapping activities, complex markets, digital ecosystems, or heavy data needs.
During pre-notification, the parties engage with DG COMP to align on:
- Scope of information to be provided
- Market definitions that may matter
- Draft versions of the filing form
- Data format and methodology (e.g., market share calculations)
- Whether simplified treatment might apply
This stage can be quick for straightforward cases, but it can also take weeks or months if the case is complex or the data is messy. The parties’ main responsibility is to deliver complete, consistent information early so the Commission can accept the formal filing without repeated rework.
Formal notification: what “complete filing” really means
Notification is the official filing submitted to the Commission. The Commission will only start the formal review clock when it considers the submission complete.
A filing is not “complete” just because a document was uploaded. The Commission typically checks whether:
- Required fields are answered
- Supporting documents are provided (internal decks, strategy papers, reports)
- Data is coherent across sections
- Market contact lists are usable for third-party outreach
If the Commission requests missing information, the start date may slip. For deal teams, this is where disciplined document management and version control become essential.
Phase I: the initial review period
Phase I is the Commission’s first-pass assessment. Most non-problematic deals are cleared here, often unconditionally.
During Phase I, the Commission:
- Reviews overlaps and vertical relationships (supplier/customer links)
- Contacts customers, competitors, and other stakeholders
- Tests whether the deal could raise prices, reduce quality, or limit innovation
- Assesses whether concerns are plausible and supported by evidence
The parties’ responsibilities during Phase I typically include responding quickly to clarifying questions, preparing internal explanations for apparent market share spikes, and ensuring that third-party messaging is consistent and accurate (without orchestrating responses).
If competition concerns appear, the parties may consider remedies early. Even in Phase I, timing can become tight if remedies are discussed late.
Remedies: when commitments become part of the schedule
If the Commission identifies competition concerns, it may accept commitments (remedies) that remove the issue. Remedies can be:
- Structural (e.g., divesting a business line, assets, brands, or customer contracts)
- Behavioral (e.g., access obligations, interoperability commitments, non-discrimination rules)
Structural remedies are often preferred where feasible because they can be easier to monitor long-term. But they also require significant preparation: identifying what will be sold, defining the perimeter, preparing an information package, and often proposing a suitable buyer.
The parties are responsible for crafting a remedy package that is workable, measurable, and fast enough to implement. Remedy negotiations can become the main determinant of the real-world closing date.
Phase II: the in-depth investigation
If Phase I cannot resolve concerns, the Commission opens Phase II. This does not mean the deal is “doomed,” but it does mean the review becomes significantly more detailed.
In Phase II, the Commission may:
- Send extensive information requests
- Conduct deeper economic analysis (including pricing, bidding, diversion, and innovation)
- Perform broader market testing with stakeholders
- Hold state-of-play meetings to communicate concerns
- Consider a prohibition decision if remedies cannot fix the problem
For the parties, Phase II requires heavier internal coordination. The most time-consuming tasks usually involve building datasets, validating internal documents, preparing responses across multiple business units, and aligning strategy between merging parties—especially if they are competitors.
“Stop-the-clock” and information requests: practical timing risks
Even with formal deadlines, real timing can expand when the Commission requests information that takes time to compile. In more complex cases, the review timetable can effectively pause if responses are delayed, incomplete, or inconsistent.
To reduce timing risk, parties often:
- Pre-build a data room specifically for merger control materials
- Assign owners per dataset (sales, pricing, tenders, pipeline, churn)
- Maintain a consistent market definition and segment taxonomy across responses
- Use audit-friendly calculations that can be replicated
The Commission’s timeline is formal, but the parties’ ability to respond is what often controls the calendar.
A practical timeline snapshot (typical sequencing)
Exact durations vary by case complexity, but deal teams commonly plan around these steps:
- Pre-notification: variable (can be short or extended)
- Phase I: an initial fixed review period once accepted as complete
- Phase II (if opened): a longer in-depth period, often with additional procedural steps and remedy windows
Instead of relying on generic estimates, companies usually build a closing plan with buffers for:
- Pre-notification iteration cycles
- Potential remedy design and market testing
- Internal document collection and translation needs
- Parallel foreign filings (UK, US, or Member State reviews outside EU jurisdiction)
What companies should do early to avoid delays
Most avoidable delays come from process management rather than legal theory. The following steps usually pay off quickly:
- Start jurisdiction and turnover analysis as soon as exclusivity looks likely
- Appoint one internal point person for data and one for documents
- Create clean team rules for sensitive information exchange
- Prepare a consistent “market narrative” backed by evidence
- Track third-party stakeholders who may be contacted by DG COMP
- Build time for remedies even if you believe the case is simple
The goal isn’t to “spin” the Commission; it’s to reduce friction by providing clear, verifiable facts in a format the case team can use.
Common misconceptions that create deal surprises
A few misunderstandings repeatedly cause late-stage stress:
- “We can close while the review is ongoing.” If EU notification is required, closing early is typically prohibited.
- “Market shares are easy to compute.” In real markets, definitions, segments, and data sources can be disputed, and internal numbers may not match external reports.
- “Phase II means automatic failure.” Many Phase II cases clear, but the resource cost and time impact are real.
- “Behavioral remedies are always simpler.” They can be complex to monitor and may face skepticism depending on the market.
Treat EU merger scrutiny as a core deal workstream—similar in importance to financing, tax structuring, and integration planning.