The UK Merger Control Framework Continues to Evolve in 2026

2025 proved to be a year of major overhaul for the UK’s Competition and Markets Authority (CMA). Indeed, since the introduction of its 4Ps framework—designed to improve pace, predictability, proportionality and process—the CMA has implemented (or begun implementing) around 75 reforms. 2026 is already shaping up to be a year of further reforms; if not driven by the CMA itself, then by the UK government’s efforts to ensure that the UK competition framework continues to deliver on its objectives, including promoting effective competition and, increasingly importantly, supporting economic growth in the UK.

On 20 January 2026, the Department for Business and Trade (DBT) published its consultation focused on proposed reforms to the UK competition regime (the Consultation),¹ following the UK government’s earlier commitment to “re-energise the regulatory system”. Key proposals in the Consultation, which build on these previous commitments (see our Q1 2026 Update), include:

• Decision-Making at Phase II: As anticipated, the government is proposing to replace the panel model for decision-making at Phase II with sub-committees made up of non-executive members of the CMA Board, non-CMA staff experts and CMA senior staff (including executive or senior directors). While the CMA Board would be permitted to take Phase II decisions, it will “typically” delegate those decisions to sub-committees. The CMA has suggested that this change could make outcomes more consistent and predictable, as the CMA Board will be able to ensure decision-makers have regard to CMA policy (including the 4Ps).
• Clarifying Jurisdictional Thresholds: The government confirmed that the UK’s voluntary notification system is here to stay, but indicated that it is considering making important clarifications regarding the jurisdictional thresholds to provide greater clarity for businesses. This includes a closed list of factors relevant to determining whether “material influence” will arise,² and a defined set of criteria for assessing “shares of supply”.³
• Remedy Timelines at Phase I: The CMA currently has 10 working days from when the parties receive the Phase I decision to consider whether to provisionally accept any remedies (also known as undertakings in lieu of reference) proposed by the parties at Phase I;⁴ however, the government proposes to increase this to 20 working days. Parties would still need to submit their proposed remedies by working day five (unless granted an extension by the CMA), but the CMA would then have additional time to consider the remedies. This proposal sits alongside the CMA’s recent emphasis on early engagement throughout Phase I and could make a meaningful difference to the ability to agree remedies at Phase I in fringe cases.⁵

The CMA has already confirmed that it supports most of the reforms proposed in the Consultation, including the changes to the Phase II decision-making procedure. Importantly, the CMA insists that judicial review by the Competition Appeal Tribunal (CAT) will continue to provide “close legal oversight” of decisions.⁶ However, the CAT’s recent judgment in Spreadex—upholding the CMA’s decision to unwind the acquisition of Sporting Index—demonstrates the limits of CAT oversight in practice. While the CAT noted that it will not always show significant deference to the CMA on certain aspects of the CMA’s review, it is clear that a CAT review—under the judicial review standard—is a narrow backstop for parties, and should not be viewed as a reliable route to challenge the substance of a CMA decision.⁷

While the government has been spearheading further reforms, the CMA has continued to settle into its role as a more proportionate enforcer, with Doug Gurr (ex-Amazon UK Country Manager) recently appointed as the permanent CMA Chair. However, as is apparent from the CMA’s approach in the context of each of the following transactions, proportionate enforcement should not be construed by merging parties to mean zero or no enforcement, particularly where the relevant transactions give rise to UK-centric issues with UK complainants:

• Unwinding Aramark’s Completed Acquisition of Entier⁸: In January 2026, the CMA found that Aramark’s completed acquisition of Entier gave rise to competition concerns in the Offshore Infrastructure Market in the UK, and ordered a full divestiture of Entier UK.⁹ While the CMA’s recent decisional practice has, on the whole, shown that the CMA is cognisant of its pro-growth mandate, this particular decision demonstrates that it is not ‘open season’ for deals and the CMA will act decisively, even in the context of completed acquisitions. Notably, Aramark sought to challenge the CMA’s decision but submitted its notice of application just under one day late and the CAT refused to extend the deadline, effectively sealing the fate of the CMA’s ordered divestiture.
• Provisional Concerns in Getty Images/Shutterstock¹⁰: While the CMA has dropped its concerns relating to the supply of stock content globally (just days after the US Department of Justice unconditionally cleared the deal), its Phase II investigation has thus far confirmed the existence of provisional competition concerns in the supply of editorial content in the UK and the CMA already invited comments on potential remedies (including, at least, the divestment of Shutterstock’s paparazzi brands). As such, this deal could possibly stress test the limits of the CMA’s commitment to the growth agenda and, while the CMA would be justified in acting to address UK-specific concerns, there is a risk that in doing so the CMA could again find itself in the unenviable position of standing alone to block a global deal that has otherwise been cleared by major regulators, that is, unless workable UK-specific remedies can be agreed.¹¹ This is likely to be a position that the CMA is keen to avoid occurring given that the current pro-business reforms have, at least in part, been driven by the criticism the CMA faced when it initially found itself in a similar position in Microsoft/Activision.
• CMA’s ‘Hybrid’ Jurisdiction in CRH/Gibson¹²: Following its introduction in January 2025, the CMA has only invoked its ‘hybrid’ jurisdictional threshold on a few occasions.¹³ However, the approach the CMA adopted to establish jurisdiction in CRH/Gibson—which was eventually cleared unconditionally at Phase I—demonstrates that the threshold provides the CMA with wide jurisdictional reach. In CRH/Gibson, the CMA claimed jurisdiction via CRH having a 33% share of supply with respect to the supply of a particular product (crushed rock aggregates) in a certain area that was considered to be a substantial part of the UK. Interestingly, the CMA’s substantive assessment then proceeded to define the relevant product market more broadly (the supply of non-specialist aggregates), with this product market also not being one of the main focal points of the CMA’s review. As such, this case makes it clear that the CMA retains considerable discretion to assert jurisdiction over large incumbents with significant shares of supply in the UK, even in markets that are not at the core of the relevant transaction.

Fine-Tuning the UK National Security and Investment Act

In March 2026, the UK government confirmed important changes to the UK National Security and Investment Act (NSIA), including extending the mandatory notification regime to the water sector, breaking out separate schedules for Critical Minerals and Semiconductors, and finessing the scope of the Artificial Intelligence Schedule to exclude, inter alia, ‘off the shelf’ artificial intelligence. Pending the changes being laid before Parliament later this year, the current schedules remain effective. Further information on the upcoming changes can be found in our recent client alert.

Although there have been no NSIA Final Orders issued so far this year, it should not be assumed that the UK government has become any less rigorous in its approach to national security and investment screening—even outside of NSIA jurisdiction—especially at a time of war in the Middle East (in addition to ongoing conflict in the Ukraine). In March 2026, the UK government issued a Ministerial Statement¹⁴ seeking to block Ming Yang—a privately owned Chinese company listed on the London Stock Exchange (LSE) and Shanghai Stock Exchange—from providing innovative wind farm/renewables technology to Octopus Energy and other stakeholders and building a factory in Scotland to produce wind turbine products including floating platforms, citing national security risks.¹⁵ This was despite support from local stakeholders in Scotland (including the likes of Scottish Deputy First Minister, Kate Forbes, and customers) and Ming Yang offering up commitments in order to safeguard data and ensure cybersecurity. Taken against the backdrop of the Business and Trade Committee’s inquiry into the UK–China economic relationship—including a Call for Evidence on the benefits of Chinese patient capital, as well as potential risks from Chinese investments in certain higher risk sectors¹⁶  the government’s decision, despite the lack of clarity regarding the precise legal grounds for seeking to block Ming Yang’s investment, highlights that deals in sensitive, priority sectors such as energy security will be assessed holistically for national security and investment risks, with political considerations carrying real weight.

^{1 The Consultation closed for feedback on 31 March 2026. See the Consultation here.}

^{2 The proposed closed list of statutory factors relevant to the assessment of material influence (and de facto control) includes: (i) shareholding or voting rights thresholds (for example, at least 15%) or any shareholding or voting rights in combination with other factors; (ii) board representation or appointment rights; (iii) special voting rights or veto rights over strategic decisions; (iv) access to confidential strategic information; and (v) commercial, financial, or consultancy arrangements.}

^{3 The proposed closed list of statutory criteria relevant to the assessment of shares of supply includes: (i) value; (ii) cost; (iii) price; (iv) quantity; (v) capacity; and (vi) number of workers employed. These are already set out in the Enterprise Act 2002, but the government effectively proposes to remove the existing catchall language – “some other criterion, of whatever nature” – that currently provides the CMA with broad discretion to apply any other criteria it deems appropriate when determining shares of supply.}

^{4 Parties have five working days from receipt of the Phase I decision to submit a Phase I remedy offering.}

^{5 Notably, the CMA has previously indicated that it had “limited time to assess [proposed remedies] in detail” in context of the Getty Images/Shutterstock transaction, where the parties provided a written proposal on the day of the deadline for submitting Phase I remedies (see here).}

^{6 See the CMA’s response to the Consultation here.}

^{7 See the CAT’s decision on Spreadex Limited v Competition and Markets Authority here.}

^{8 See the Aramark/Entier case page here.}

^{9 While Aramark submitted an initial remedy proposal intended to address the competition concerns the CMA articulated in its Phase II Interim Report, which included a divestment of a sub-set of one of the parties’ relevant contracts and the transfer of those members of staff serving those contracts directly, Aramark later withdrew its proposal and did not make an alternative offer (and also declined the CMA’s offer of a remedies meeting).}

^{[10] See the Getty Images/Shutterstock case page here.}

^{11 The parties offered up a divestiture of the Splash News and Backgrid brands and the CMA is engaging with third parties on the robustness of this offering, including whether the assets in question are sufficient to address the substantial lessening of competition provisionally found in the supply of editorial content in the UK. The invitation to comment on remedies, available here, closed on 18 March 2026.}

^{12 See the CRH/Gibson case page here.}

^{13 The hybrid jurisdictional threshold is satisfied where: (i) one party supplies or acquires at least 33% of goods or services of any description in the UK (or a substantial part of the UK); (ii) the same party has a UK turnover in excess of GBP 350 million; and (iii) another party has a UK nexus (a broadly defined concept meaning it is registered in the UK, carries on activities in the UK, or supplies goods or services to UK customers).}

^{14 See the statement from the Minister for Energy here.}

^{15 Reportedly the US government had raised concerns with the UK government back in June 2025 about national security risks arising from proposals for the Chinese company to supply wind turbines to North Sea wind farms (see the Financial Times article here)}

^{16 The inquiry addresses the economic relationship between the UK and China, considering key issues regarding engagement with China, competition, supply chain security, investment security, control of strategic technologies and data security. The inquiry, available here, is accepting evidence until 10 April 2026.}