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25 September 2025

Class Actions Radar: United Kingdom – Competition

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Herbert Smith Freehills Kramer LLP

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The UK has a separate regime for collective claims based on infringements of competition law, which are heard by the Competition Appeal Tribunal (CAT).
United Kingdom Antitrust/Competition Law
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The landscape

The UK has a separate regime for collective claims based on infringements of competition law, which are heard by the Competition Appeal Tribunal (CAT).

Its scope was significantly expanded in 2015. Claims can be brought by a Class Representative on behalf of consumer or business claimants, seeking aggregate damages on either an opt-in or opt-out basis. Claims may be "follow-on", based on an existing decision by a competition regulator finding a competition law breach, or "standalone", without any underlying infringement decision. 

The landmark Supreme Court judgment in Merricks v Mastercard in December 2020 gave this avenue considerable momentum by setting a very low bar for certification of claims by the CAT (certification being the initial procedural hurdle before the claim can proceed to trial). Since then, there has been a significant increase in claims filed (30 have been filed in the last three years alone, compared to just 9 in the five-year period prior to the Merricks judgment).

A number of recent cases have seen certification refused outright. The reasons for this have been varied, and highly case specific, but this series of cases shows that even if the bar for certification is low, certification is a battle defendants can win in the right case.

Joe Williams
Partner

Growth in competition class actions is further fuelled by increased availability of litigation funding (with the potential for significant returns proving very attractive to funders), broad disclosure rules and the CAT's willingness to engage in sophisticated economic analysis and detailed consideration of complex legal tests. No claims have yet resulted in an award of aggregate damages. Judgment in the first full trial of opt-out competition collective proceedings, Le Patourel v BT Group, was handed down at the end of 2024 and the claim was dismissed. A large number of further cases have passed through the certification stage and judgment is awaited in respect of a further three substantive trials, with further trials entering the CAT's diary on a regular basis.

There have also been a number of settlements reached, with one so far having resulted in distribution to class members.

As a result of all of this, ten years on from the regime's inception, we are only now starting to see evidence of the financial outcomes the regime can deliver.

Marking a decade since the regime was broadened, in August 2025, the UK's Department for Business & Trade announced a review of the collective proceedings framework and invited a "call for evidence" to examine whether and what changes to the regime may be beneficial. Although there is no expected date for the results of this review, its outcome could shape the future trajectory of collective proceedings in the UK.

Current developments

While we continue to see a number of "plain vanilla" follow-on claims, there is a growing trend towards standalone claims, often rooted in allegations of abuse of dominance but pursuing novel theories of harm.

Such claims often stem from a perceived regulatory gap, with Class Representatives being creative in arguing that claims involving matters such as consumer rights and data privacy – or even environmental issues – amount to an abuse of a dominant position, in order to claim aggregate damages under the opt-out collective competition claims regime. Recent examples have included claims in relation to mobile phone loyalty "penalties", "throttling" of iPhone batteries and alleged misreporting of sewage discharges by water companies (albeit the latter case was dismissed at the certification stage on the basis that the claim was ousted by sector specific legislation).

Class Representatives may also seek to use the opt-out regime to obtain redress for consumers where a regulator has adopted a forward-looking solution following a review of issues in a particular sector (such as a regulatory change or acceptance of voluntary commitments), without any compensation for those previously affected.

The willingness of the UK Competition Appeal Tribunal to accept claims being "shoe-horned" into the opt-out competition class actions regime on the basis of novel theories of harm rooted in abuse of dominance allegations – at least at the certification stage – means that the risk of competition class actions in the UK now extends well beyond the sort of practices traditionally seen as likely to give rise to substantial damages actions.

Kim Dietzel
Partner

Future trends

The UK will likely remain one of the most popular jurisdictions to bring competition class actions.

However, it remains to be seen how the level of damages awarded – if any – in high-profile upcoming substantive trials impacts availability of funding for future claims.

2025 has seen a number of cases refused certification outright. The reasons for certification being refused have varied, but include the Proposed Class Representative not meeting the authorisation criteria, the claim being successfully struck out (and also not having a valid methodology), and claims being ousted by sector specific legislation. Whilst the threshold for certification remains low, this series of cases demonstrates that there is still scope for certification to be a battle defendants can win in the right case.

As more claims move beyond the initial certification stage, there will inevitably be more focus on distribution of damages to class members. To date there has only been distribution of one settlement, which was not very successful (only approximately 0.8% of the settlement pot was distributed to class members). Care should be exercised before reading much in to this sample size of 1, but on any view it is a low figure and the Tribunal has acknowledged that this distribution was not very successful and so ordered that 16% of the total remaining settlement pot be paid to the Access to Justice Foundation (before the Funder was allowed to claim any of the undistributed amounts). It remains to be seen whether future distributions are more successful, and we expect it will continue to be an area of heightened scrutiny for the Tribunal.

The majority of settlements have been agreed to by all parties (the Class Representative, the Defendant(s) and the Funder). However, in an unusual turn of events, in the recent Merricks settlement, the settlement was not approved by the litigation funder. The Funder argued that the level of the settlement was too low (£200m, when the claim was originally estimated to be between £10-14bn) and premature. This was rejected by the Tribunal who concluded that the settlement was just and reasonable. The Tribunal also determined that it was able to set the level of return owed to the Funder independently of the agreement between the Funder and the Class Representative, resulting in the Funder receiving a much lower return than they had anticipated. The Funder is judicially reviewing this decision.

Next steps for business

Tailored compliance training:  The most important first step for businesses to minimise the risk of competition class actions is to deliver regular tailored compliance training to employees. This is designed to reduce the risk of competition law infringements in the first place. A wide range of anti-competitive conduct could potentially give rise to a claim, or indeed multiple claims at different levels of the supply chain.

Ensure subsidiaries are compliant: Larger company groups should ensure that subsidiaries – including non-UK subsidiaries – understand the importance of competition law compliance. This is because claimants may seek to establish an "anchor defendant" in a claimant-friendly jurisdiction such as the UK. 

Stay informed of latest trends:  Businesses should be alert to current "hot topics" for competition regulators. These may represent areas of greater risk for both investigations and damages claims. Current areas of focus include the application of competition law to collaboration between competitors on ESG initiatives to achieve sustainability goals, and the impact of non-poaching agreements and wage-fixing agreements on competition in labour markets.

Know the scope of the risk: It is also important to recognise that the CAT's willingness to accept novel theories of harm – at least at the certification stage – means the risk of a competition collective damages claim now extends to a broad set of business practices. For businesses that could be considered to hold a dominant position in a particular market, this risk is heightened and may extend to conduct which arguably falls within "market practice" or is associated with particular business models, particularly in connection with the use of AI/algorithms and data. It can be difficult to fully mitigate these risks, beyond ensuring that the legitimate rationale for key decisions is clearly recorded.

Notable cases

The CAT has handed down four judgments approving settlement in opt-out competition collective proceedings (two in Maritime Car Carriers, one in Boundary Fares and one in Merricks). Any settlement agreed by the Class Representative with one or more defendants in a certified opt-out claim must be approved by the CAT, and these judgments provide helpful guidance for businesses considering whether to settle a claim, and if so on what terms. As noted above, the Merricks settlement created an unusual situation where the Funder was objecting to both the level and the terms of the settlement. The Tribunal made it clear that it did consider the settlement to be just and reasonable – whilst the settlement figure was far lower than that initially put forward by the Class Representative, it was clear following a number of Tribunal decisions and evidence received during the course of proceedings that the original damages figure was not a realistic estimate of the potential loss suffered by the class.

There have also been a number of important judgments on the validity of litigation funding agreements for competition collective proceedings following the Supreme Court judgment in PACCAR in July 2023, holding that litigation funding agreements were Damages Based Agreements (Alex Neill v Sony, CICC I v Mastercard and Gutmann v Apple). In July 2025, the Court of Appeal upheld a decision of the CAT that agreements whereby the Funder's return is calculated as a multiple of capital invested, rather than a percentage of damages or settlement, are not DBAs, notwithstanding the fact that the return will ultimately be capped by the damages recovered.

In Professor Carolyn Roberts v Severn Trent Water Limited & Ors the Tribunal refused certification outright on the basis that it was not permissible to bring a claim for damages for an alleged breach of competition law, as an 'essential ingredient' of the claim was that the water companies had breached their licences, and under the Water Industry Act 1991 remedies for a breach of the licence are those expressly set out within the Water Industry Act 1991, and so a claim for a breach of competition law was 'ousted'. The Tribunal held that if the claim had not been ousted by the Water Industry Act 1991 it would have met the certification criteria. This judgment demonstrates that there is a limit to the ability to 'shoehorn' cases into the CPO regime, and that certification remains a meaningful battleground.

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.

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