Driving uncertainty: Below threshold M&A is not safe from merger control review

China the standout enforcer  

The State Administration for Market Regulation (SAMR) ramped up its scrutiny of below-threshold deals last year, particularly in sensitive sectors.

It used these powers to flex its muscles in high-profile global tech M&A, calling in the semiconductor deal between Synopsys and Ansys and Keysight’s acquisition of network and cybersecurity testing firm Spirent. In each case SAMR intervened, clearing the transactions only after securing remedies. The review of its first called in below-threshold transaction in the internet platform sector is ongoing. 

Closer to home, SAMR went one intervention step further. After calling in a domestic pharmaceuticals merger six years after it completed, it required the transaction to be unwound (see Fewer roadblocks for M&A: Politics play into lighter touch merger control enforcement for more). This marked the authority’s first prohibition of a non-notifiable deal. 

It was not an isolated case: the authority’s second below-threshold block came in early 2026, in the utilities sector. The risks are rising for Chinese deals.

Elsewhere in APAC, despite the shift to a mandatory system, Australia has retained a general prohibition against all transactions that substantially lessen competition. This applies to deals falling below the new filing thresholds. We expect ongoing scrutiny of below-threshold matters and that merging parties may opt to file such deals with substantive overlaps on a voluntary basis. 

Calling for call ins in the EU 

EU member states with powers to call in below-threshold deals are using them. Since 2023, for example, the Italian Antitrust Authority has called in ten transactions, two of which resulted in remedies and one that was abandoned.  

Many more member states are looking to introduce below-threshold call-in provisions. This includes the Czech Republic, France, the Netherlands, Romania, and Slovakia. Even Germany, historically a critic of such mechanisms, is reconsidering its position after a supreme court ruling failed to shed light on the unclear applicability criteria of the German deal value threshold. 

In the interim, authorities are making use of behavioral antitrust rules to assess deals not caught by merger control regimes:  

• In France, a EUR4.7 million abuse of dominance fine on Doctolib included a (symbolic) sum for acquiring its main rival in 2018.   
• A rule change in the Netherlands means below-threshold transactions can now be assessed as a possible abuse of dominance, and the Authority for Consumers and Markets (ACM) has an ongoing antitrust investigation of a below-threshold M&A deal.
• The Belgian Competition Authority launched two probes into non-notifiable mergers: a flour mills transaction (ultimately abandoned by the parties) and Live Nation’s acquisition of the Pukkelpop music festival. 

All quiet on the EC front  

While EU member states have been busy, the European Commission (EC) has kept a low profile on call-ins following the European Court of Justice’s ruling in Illumina/GRAIL.  

The court annulled the EC’s prohibition of the deal and confirmed that Article 22 referrals can be made only by member state authorities that have jurisdiction under their national regimes—a clarification that undermines key aspects of the EC’s former strategy for capturing transactions falling below national thresholds.   

A core part of Competition Commissioner Ribera’s mandate is to work out how to deal effectively with “killer acquisitions.” This is something she pledged to tackle early in her term.  

For now, the EC seems content to encourage member states to expand their jurisdictional reach and then refer any potentially problematic mergers to it.  

But this route has so far only yielded one referral (Nvidia/Run:ai), which was challenged by the parties before the General Court.  

The hotly anticipated ruling on the appeal will confirm whether the EC may accept an Article 22 referral where the referring authority relies solely on discretionary call-in powers rather than traditional jurisdiction based on national merger control thresholds (an issue left open by Illumina/GRAIL). The court is expected to look carefully at how this policy impacts legal certainty for merging parties.  

Information is power 

Some jurisdictions are seeking more avenues to learn about below-threshold M&A, which may result in a further uptick in scrutiny of such deals.

Imposing “prior approval” style merger remedies

Used frequently in the U.S., these require an acquirer to inform the authority about certain future deals for a specified period, usually regardless of whether filing thresholds are met. We have recently seen them in jurisdictions such as Brazil.

In the EU, they are also a feature of other regulatory toolkits. One of the commitments in the EC’s first conditional clearance under the Foreign Subsidies Regulation was a requirement to inform the authority of all future acquisitions. Under the EU Digital Markets Act, firms designated as “gatekeepers” must inform the EC of all deals involving digital services or that enable the collection of data.  

Obligations following a sector inquiry 

The German Federal Cartel Office has the power to order firms that have been subject to a sector inquiry to notify all acquisitions for a three-year period. It made use of this for the first time in 2025 against Rethmann Group, requiring notification of future acquisitions in the non-hazardous household waste sector. 

Australia has effectively applied a similar system, allowing the responsible minister to proscribe transactions in particular sectors. With a nod to political sensitivity over cost-of-living pressures, most acquisitions by major supermarkets are mandatorily notifiable irrespective of the applicable thresholds.

General information-gathering initiatives

In a new form that must be submitted prior to a formal Dutch merger control notification, the ACM asks for an overview of all deals in the past five years. Japan has launched a non-case-specific form for businesses and individuals to submit comments on transactions, including below-threshold deals. And the Canadian Competition Bureau is using court orders to compel the provision of information about transactions, even if not notifiable.