England and Wales has been one of the leading jurisdictions for antitrust litigation in Europe for over 30 years. The combination of a well-regulated jurisdiction for commercial litigation, specialist competition judges and an expert tribunal (the Competition Appeal Tribunal or CAT), and wide-ranging disclosure has made the UK an attractive destination for antitrust damages claims. In addition, following the introduction of opt-out collective actions before the CAT in 2015 there has been substantial growth in those claims, although there has been a marked slowdown in applications in 2025. 

The legislative framework for assessing potential competition law infringements comprises the Competition Action 1998 (“CA 98”), as amended by the Enterprise Act 2002, and the Consumer Rights Act 2015 which introduced collective proceedings for claims seeking redress for breaches of competition law. The CA 98 sets out: (i) the Chapter I prohibition, which prohibits agreements that have as their object or effect the prevention, restriction or distortion of competition; and (ii) the Chapter II prohibition, which prohibits the abuse of a dominant position. 

Claims for damages may be brought for breach of statutory duty where the CA 98 Chapter I and Chapter II prohibitions have been infringed. These may be brought on a standalone or follow-on basis, and since the introduction of the Consumer Rights Act 2015 (the CRA 2015), collective actions have been available in the CAT for follow-on and standalone antitrust damages claims, Claims may be brought on an opt-in or opt-out basis.

Legislative Developments

Digital Markets, Competition and Consumers Act 2024

On 1 January 2025, the Digital Markets, Competition and Consumers Act 2024 came into force. This Act contains important amendments to the existing competition regime. In relation to private litigation in particular, Part 2 includes provisions to expand the Tribunal’s jurisdiction to include the ability to grant declaratory relief.

Potential reform of the opt-out collective actions regime

On 6 August 2025, the government announced a review of the operation and impact of the opt-out collective actions regime in particular: access to, and the framework for, funding cases within the regime; the scope and certification of cases; ADR, settlement and damages; and the distribution of funds. The consultation notes that the tens of billions of pounds in damages claimed and hundreds of millions of pounds spent on legal fees is far higher than estimated in the original impact assessment. It also said that while the expectation was that the majority of cases would be follow-on, approximately 90% of the current caseload is made of standalone cases. The government is considering how alternative dispute resolution and voluntary redress schemes could be made more effective and has formed the view that bringing a claim should not be the primary route to redress for consumers where they have suffered loss as a result of anti-competitive behaviour. The consultation closes on 14 October 2025.

Landmark cases

England and Wales is a highly active jurisdiction with dozens of judgments issued in private antitrust litigation cases. It is not possible to summarise all of the relevant developments, but we summarise below a handful of the key recent cases.

In July 2025, the Court of Appeal issued judgment in Phones 4U Limited v EE Limited and others [2025] EWCA Civ 869. This was an appeal by Phones 4u against the dismissal of its claim that it had been the victim of alleged collusive anti-competitive schemes in which senior executives of three mobile network operators and their respective parent companies had participated between 2012 and 2014.

The judgment considered a wide range of grounds of appeal, but two areas in particular are of relevance to those involved in standalone cartel claims, particularly involving allegations of information exchange. At first instance, Roth J found that O2’s CEO was “sounding out” EE’s CEO as to whether, if O2 reduced the volume of supplies it made via indirect retailers, EE would not take up that volume. This was found to be an invitation to collude by O2, but the judge accepted EE’s evidence that its CEO essentially did not engage and remained passive, until the conversation moved on. He also found that the remarks were “too vague” to remove uncertainty for EE as to O2’s future conduct.

The Court of Appeal considered whether a passive response to the disclosure of confidential information from one competitor to another was sufficient to infringe competition law. It found that it was not in the circumstances of this case and that the High Court had committed no error of law. In setting out the principles, the Court of Appeal held that some reciprocity is required and that may be satisfied where a disclosure of future intentions is made to a competitor who either accepts it or requests it. While the case law is not always clear on what “accepts” means, there must be a consensus of some form. It further found that the conduct must at least be capable of reducing uncertainty and, in this case, the judge was entitled to conclude that the information was too vague to reduce uncertainty. The Court of Appeal also found that concertation requires an element of consensus, which will depend on the context. Where there is an unanticipated “one-way” communication of confidential information, whether a passive response is taken as tacit approval will depend on the facts. In many circumstances, a failure to object will be seen as tacit approval and it is entirely possible that the discloser of the information, may also derive something from the recipient’s reaction, even if it is entirely passive.

The Court of Appeal also considered whether the “Anic” presumption can be rebutted by anything other than public distancing or a report to the competition authorities. The Anic presumption means that undertakings participating in concerted practices and remaining active on the market are presumed to take account of the information exchanged with their competitors when determining their conduct on the market. At first instance, despite finding that there had been no “concertation”, Roth concluded that EE had rebutted the Anic presumption by signing a new three-year deal with Phones 4u.

In considering whether this amounted to an error of law, the Court of Appeal found that there is an additional presumption contained in Anic: that participating in a meeting at which an anti-competitive agreement/concerted practice is concluded without public distancing is presumed to amount to participation (the “participation” presumption). The Court of Appeal found that public distancing is not essential to rebut the Anic presumption, was not supported by any authority, lacked logic and would lead to unprincipled differences of approach depending on whether there had been a meeting between competitors. The Court also found that the presumption only applies to those receiving information. On the facts of this case, EE’s CEO conveyed nothing to O2’s CEO, so there was nothing that O2 gleaned from the meeting which could have influenced O2’s conduct.

Limitation

We have also seen important developments in the context of limitation.

The limitation rules in competition claims are complex and depend on: (i) whether the claim is brought in the CAT or the High Court; (ii) whether the claim is standalone or follow on; (iii) when the claim is issued; and (iv) when the infringement of competition law occurred.

At first instance in the MIF Umbrella and Merricks proceedings [2023] CAT 49, the claimants argued that a post-Brexit decision of the Court of Justice of the European Union (Case C-267/20, Volvo AB and DAF Trucks NV v RM, EU:C:2022:494) meant that limitation periods in a claim for damages for competition law infringements could not begin to run until: (i) the time when the infringement of competition law had ceased; and (ii) when the injured party knows, or can reasonably be expected to know, the fact it has suffered harm as a result of the infringement and the identity of the perpetrator. This would have marked a significant change to the limitation rules which apply for damages suffered prior to 9 March 2017 which currently, for example, only allow for a two-year limitation period for proceedings that commenced after 1 October 2015 where the facts giving rise to the claim arose before 1 October 2015, when brought in the CAT and relate to standalone competition claims. If the claimants were correct, this would mean the limitation period could not begin to run until the infringement of competition law ceased and the injured party could be reasonably expected to know the fact it suffered harm and the identity of the perpetrator, potentially extending the limitation period significantly. The claimants argued that the CAT was bound to follow this decision despite it being handed down post-Brexit. The CAT disagreed with the claimants’ analysis as to the effect of the CJEU’s judgment and also found that, in any event, the CAT was not bound to follow the decision post-Brexit.

The Court of Appeal recently upheld the CAT’s judgment in December 2024 ([2024] EWCA Civ 1559), confirming that a so-called cessation requirement is not part of English law for limitation periods to start, providing clarity that the limitation periods in English law have not been revised.

In a further judgment, in Lundbeck v Secretary of State for Health and Social Care [2025] EWCA Civ 677, the Court of Appeal clarified the application of the limitation rules when a claim is issued in the High Court but transferred to the CAT. The claim involved a standalone claim for damages for breaches of Article 101 which was transferred from the High Court to the CAT by way of a consent order. That order made clear that the transfer would not alter, limit or exclude any accrued rights including as to limitation. This was important because the High Court claim had been filed out of time. The Court of Appeal held that once a transfer has taken place, the proceedings were CAT proceedings and were subject to the provisions on limitation in the CAT rules (which were more generous in the circumstances of this claim), even if the High Court proceedings were time-barred. 

Collective actions

There have also been a number of important developments in collective action proceedings before the Competition Appeal Tribunal.

Certification

The certification process for collective proceedings brought in the CAT has been heavily litigated since the regime was introduced in 2015. Under Section 47B of the CA 1998 (as amended by the CRA 2015), any collective proceedings may only proceed if the CAT makes a collective proceedings order.

Since the 2020 Supreme Court judgment in Walter Merricks CBE v Mastercard Incorporated & Ors [2020] UKSC 51, the bar to certification has generally been considered to be relatively low, with the vast majority of cases being certified. However, there have been two recent cases where a collective proceedings order has not been made which may indicate a trend towards greater scrutiny of certification applications in the CAT.

The first was in the case Christine Riefa Class Representative Limited v Apple Inc. & Others [2025] CAT 5, where the Competition Appeal Tribunal refused the application for certification on the basis that the Tribunal did not consider the Proposed Class Representative (PCR) satisfied the authorisation conditions to be a Class Representative. A PCR must demonstrate that they are capable of acting fairly and adequately in the interests of class members in order to fulfil the requirements of Rule 78(1), and a failure to do so may prevent a collective action from being certified. In the circumstances of this case and following a hearing during which the PCR was cross-examined, the Tribunal was concerned that the PCR had acceded to the funder’s request to keep the terms of its funding confidential, including from the class members whose interests she was supposed to be representing and that she did not have a sufficient understanding of the funding agreements involved.

The second failed application was in a case brought against six water and sewerage companies, Roberts v Thames Water and ors [2025] CAT 17, where the Tribunal rejected the claim as it relied on alleged infringements of a statutory regime to which the only remedy was by way of an enforcement order by the UK’s water regulator.

Judgments

In December 2024, the first liability judgment in collective proceedings was handed down in Le Patourel v BT [2024] CAT 76. The CAT found that, while BT was dominant in the relevant market of standalone fixed voice services and its prices were excessive, the prices charged were not unfair. As a result, BT had not breached competition law (and thus no damages were awarded). The judgment is the latest in a line of cases which deal with the test for unfair pricing and largely followed the Court of Appeal’s judgment in CMA v Flynn Pharma and Pfizer [2020] EWCA Civ 339. The claimants were refused permission to appeal from the CAT [2025] CAT 10 and, in July 2025, the Court of Appeal refused permission to appeal.

The judgment also made some obiter observations on the basis of the approach to quantum in unfair pricing cases. It rejected the suggestion that if BT’s prices had been found unfair, that there would have been a margin for pricing above the competitive benchmark before it would qualify as significantly and persistently above that benchmark. In doing so it relied on the CAT’s judgment in Dwr Cymru which said that a claimant showing where the line should be drawn (in terms of the counterfactual price) would be an almost impossible task that would involve the court redoing much of the work that had already been undertaken when establishing liability.

Settlements

Under the collective proceedings regime in the Competition Appeal Tribunal, any opt-out settlements must be judicially approved. The Tribunal may approve the settlement only if it is satisfied that its terms are just and reasonable.

In May 2024, the CAT approved the second collective settlement under the CRA 2015 in Justin Gutmann v First MTR South Western Trains Limited and Another [2024] CAT 32. This settlement was between the Class Representative and the second defendant, Stagecoach South Western Trains Limited (SSWT). The Class Representative claimed that SSWT, along with the other defendants, abused a dominant position by, in effect, double-charging customers for part of the service provided to them. The CAT expressed concerns about the original settlement proposal including the feasibility for individuals of recovering damages and whether the proposals for unclaimed sums were appropriate. The parties revised the settlement to reflect the CAT’s concerns and this was then approved.

In February 2025, the CAT gave an oral ruling approving the largest proposed settlement of a collective action so far in the collective action brought against Mastercard by Merricks. The claimants originally sought damages of GBP14 billion plus interest, bringing it to just under GBP20 billion claimed. The claim faced a number of hurdles along the way, with issues around limitation, causation and pass-on, ultimately narrowing the scope of the claim significantly. In December 2024, a settlement agreement was reached. The litigation funder objected to the settlement. It argued that the settlement sum was too low and that Mr Merricks should have extracted a higher sum, seeking to exert greater pressure on Mastercard to pay a higher amount. Despite this, the CAT found it to be just and reasonable. In May 2025, the Tribunal ruled on the proposed distribution of the GBP200 million. The Tribunal approved the proposal of Mr Merricks and Mastercard that: (i) GBP100 million would be ring-fenced for class members; (ii) GBP46 million would be ring-fenced as a minimum return to the funder (roughly equating to its actual expenditure); and (iii) a portion of the balance, depending on class take-up would go to the funder as profit, with the rest paid to charity. Despite strenuous objections from the funders, the CAT commended the plan which it found sought to achieve the maximum take-up of a reasonable sum by class members.

Funding

Following the Supreme Court’s judgment on 26 July 2023 in Paccar Inc and Ors v Road Haulage Association Limited and UK Claims Limited [2023] UKSC 28, Litigation Funding Agreements (LFAs), in which the funder’s return is a share of damages ultimately awarded to the claimant, are now categorised as Damages-Based Agreements (DBAs) which are not enforceable if they do not meet the requirements set out in the applicable regulations, such as capping the share of winnings at 50% and being on a no win, no fee basis. Most LFAs have now been updated to work around this ruling, with provisions such as recovering a multiple of the funds committed being applied.

In March 2024, the UK government announced the Litigation Funding Agreements (Enforceability) Bill, which sought to reverse the decision of the judgment on third-party litigation funding (R (on the application of PACCAR Inc) v Competition Appeal Tribunal [2023] UKSC 28). While this bill was ultimately not passed prior to the 2024 General Election, the Civil Justice Council 2025 review has advised that this decision should be reversed, and so we await to see if legislative reform will be introduced to address this.

Claims for damages arising from a breach of UK or EU competition law can be brought in the High Court (either in the Chancery Division or the Commercial Court) or before the CAT. In the High Court, claims are based on the tort of breach of statutory duty of Chapters I/II of the UK Competition Act 1998 (CA 1998), and/or – for conduct occurring prior to December 2020 – Section 2(1) of the European Communities Act 1972 (as preserved by Section 1 of the EU (Withdrawal Agreement) Act 2020), which imported into English law Articles 101 and 102 of the Treaty on the Functioning of the European Union (TFEU). Claims for damages before the CAT are based on Section 47A CA 1998 and/or Section 47B of the CA 1998. Section 47B CA 1998 forms the basis for collective actions before the CAT.

Standalone and Follow-On Claims

Claims may either be on a “standalone” or “follow-on” basis. In standalone claims, the claimant must establish: (i) the anti-competitive conduct of the defendant(s); and (ii) that the defendant’s/defendants’ behaviour caused loss to the claimant.

In follow-on actions, the claimant may rely on a decision by a UK competition authority (eg, the UK’s Competition and Markets Authority, or CMA) or the EC (provided it was made prior to 31 December 2020) to find an infringement of competition law. Provided that the decision is final (ie, all appeals or time limits for making appeals have been exhausted), it will be binding on UK courts, and the claimant is not required to prove the anti-competitive conduct as they would be in a standalone claim. Findings and decisions by EU member state competition authorities prior to 31 December 2020 are considered prima facie evidence of an infringement.

Specialist Courts

Standalone and follow-on claims may be brought in either the High Court or the CAT.

Comparison Between the CAT and the High Court

The CAT is a specialist tribunal which has its own rules and procedures, as well as specialist judges. The CAT hears cases in panels which typically consist of a High Court judge (as chair), and two other members who may be lawyers, judges, and relevant specialists such as economists or accountants. Proceedings in the High Court are typically presided over by a single judge who may or may not have specialist competition law expertise.

The powers of the High Court and the CAT are broadly similar for the purposes of typical competition proceedings; both can make orders for interim measures such as injunctions, and neither has a limit on the compensation it can award. However, only the CAT can hear collective actions initiated under Section 47B of the CA 1998. In the High Court, the civil procedure rules (CPR) do permit claims to be combined under a group litigation order, where those claims have “the same interest”; however, such claims are typically harder to bring, with a high threshold for determining commonality of interest between individual claims. Both the High Court and the CAT can grant declaratory relief following the Digital Markets, Competition and Consumers Act 2024, which extended this power to the CAT.

Transferral of Cases Between Courts

The High Court may transfer as much of the proceedings to the CAT as relate to the infringement of competition law. This means that claims can be transferred in whole or in part. The High Court has held that the complexity of the issues involved, the extent to which economic evidence is at issue, as well as cost implications, are all relevant to whether a transfer to the CAT will be ordered. Conversely, CAT Rule 71 allows the CAT to transfer a claim to the High Court.

Under Section 58A of the CA 1998, decisions of the CMA or of the EC (made prior to 31 December 2020), once final (ie, once all appeals have been exhausted, or the deadlines for making appeals have passed), are binding in UK courts as they relate to the existence of an infringement of competition law. In such claims, a claimant need not prove the infringement of competition law, and instead the proceedings will focus solely on the extent of the loss suffered by the claimant, and whether the claimant can establish that the defendant’s/defendants’ anti-competitive conduct caused the loss claimed.

Infringement decisions by another EU member state’s national competition authority (NCA) on EU competition law made after 9 March 2017 and prior to 31 December 2020 are treated as prima facie evidence of an infringement of EU competition law for the purposes of a claim for damages under paragraph 35 of Schedule 8A of the CA 1998.

Under paragraphs 4.1 and 4.1A of the High Court Competition Law Practice Direction, competition authorities have the right to make written observations and to apply to make oral observations on issues relating to the application of Chapter I or II of the CA 1998 and/or of Articles 101 or 102 of the TFEU. The CMA may make written observations or, with the permission of the tribunal, oral observations, in CAT cases (permission being given for the first time in a Section 47A CA 1998 claim in Epic Games, Inc and Others v Alphabet Inc, Google LLC and Others).

In both follow-on and standalone claims, the burden of proof is on the claimant. In follow-on claims the infringement decision will establish the existence of the infringement, but the claimant will have to prove that the infringement caused them to suffer loss. In a standalone claim, a claimant will have to establish the infringement and that this caused them to suffer loss. The standard of proof, as in civil claims generally, is the “balance of probabilities”.

In addition, for claims where the loss or damage occurred wholly on or after 9 March 2017, there is a rebuttable presumption that cartels cause loss or damage (see Article 17 of the EU Damages Directive and Schedule 8A paragraph 13 CA 1998).

Infringement decisions by another EU member state’s national competition authority (NCA) on EU competition law made after 9 March 2017 and prior to 31 December 2020 are treated as prima facie evidence of an infringement of EU competition law for the purposes of a claim for damages under paragraph 35 of Schedule 8A of the CA 1998.

Under paragraphs 4.1 and 4.1A of the High Court Competition Law Practice Direction, competition authorities have the right to make written observations and to apply to make oral observations on issues relating to the application of Chapter I or II of the CA 1998 and/or of Articles 101 or 102 of the TFEU.

If defendants can demonstrate that the alleged damage suffered by the claimant was passed on to the claimant’s own customers, then this may constitute a (whole or partial) defence to the claim. This is known as the “passing-on” defence. The burden of proving the pass-on defence lies with the defendant.

Damages awarded to a claimant as a purchaser of a cartelised product may be reduced if the defendant can prove that the overcharge was passed on to the claimant’s own customers.

In Sainsbury’s v Mastercard [2016] CAT 11, the CAT held that the pass-on defence is only available for identifiable increases in prices by a firm to its customers. The CAT also held that the defendant must show on the balance of probabilities that there is another class of claimant, to whom the overcharge has been passed on, in the absence of which a claimant’s damages should not be reduced. The Court of Appeal upheld the CAT’s finding that Mastercard’s defence failed because no identifiable increase in retail price had been established, let alone one causally connected to the UK Multilateral interchange fee. In an appeal from the Court of Appeal, the Supreme Court held that the Court of Appeal erred insofar as it required a greater degree of precision in the quantification of pass-on from the defendant than from the claimant. Once a defendant has raised pass-on, there is a heavy evidential burden on the claimant to provide evidence as to how they have dealt with the recovery of their costs in their business. Most of the relevant information about what a claimant has done to cover its costs will be exclusively in the hands of the merchant itself, and the claimant must produce evidence in order to forestall adverse inferences being taken against it by a court applying the compensatory principle. The Supreme Court concluded that the law does not require unreasonable precision in the proof of the amount of the prima facie loss which the merchants have passed on to suppliers and customers.

For claims where the loss or damage suffered from an infringement took place wholly on or after 9 March 2017, the claimant is presumed (subject to rebutting evidence) to have proved that the overcharge or underpayment was passed on if:

• the defendant infringed competition law;
• there was an overcharge or underpayment as a result of the infringement; and
• the product or service was provided to the customer by the claimant.

This was applied by the CAT in Royal Mail Group Limited v DAF Trucks Limited and Others, BT Group PLC and Others v DAF Trucks Limited and Others [2023] CAT 6 in which the CAT clarified that the legal test for causation in relation to a pass-on defence required the defendant to prove a direct and proximate causative link between the overcharge and any increase in prices by the claimants.

In the case of Granville Technology Group Limited v Chunghwa Picture Tubes Ltd, LG Display Co. Ltd [2024] EWHC 13, the Court addressed the issues of overcharge and pass-on in the context of a cartel’s influence on the prices of Liquid Crystal Display (LCD) panels. The claimants, manufacturers and sellers of desktop PCs with monitors and notebooks, alleged that due to the cartel’s activities, they paid inflated prices for LCD panels, constituting an overcharge. They sought to recover this overcharge as damages for breach of statutory duty. While it was undisputed that an overcharge occurred, the extent of it was contested. The defendants argued that the claimants had passed on any price increase to their customers, negating any claim of loss.

In assessing the overcharge, the court found it to be necessary to assess what would have happened had the infringement not occurred, leading to the conclusion that the overcharge rates attributable to the cartel were 8% for monitors, 4% for notebooks and 14% for TVs. When examining the pass-on to downstream customers, the court found that, in line with compensatory principles, any loss that had been passed on was not compensable. The court estimated that 65% of the overcharge was likely passed on, considering market competitiveness and the variable pass-on rates during the relevant period. Despite this, the court recognised that the claimants had suffered a significant loss of profit due to reduced sales, which they successfully demonstrated was a consequence of passing on the overcharge to their customers.

Rules on limitation differ depending on whether the claim is brought before the High Court or CAT and when the cause of action accrues (ie, when the infringement causes damage to the claimant). New limitation rules apply to claims (whether brought in the High Court or CAT) where the loss or damage took place wholly on or after 9 March 2017 (paragraphs 17–26, Schedule 8A, CA 1998). These new limitation rules displace the Limitation Act 1980 in relation to antitrust claims.

Claims Where Loss or Damage Occurred Before 9 March 2017

For High Court claims where the loss or damage occurred wholly before 9 March 2017, the limitation period is six years from the date on which a cause of action accrues. The High Court in Gemalto Holding and Thales DIS France v Infineon Technologies and ors [2022] EWHC 156 clarified that the six years starts to run when the claimant’s state of knowledge is such that it and its professional advisers can properly plead a claim that would not be liable to be struck out as unarguable or lacking sufficient evidential basis. The limitation period is not postponed until the claimant has completed its investigations or is certain that the claim will succeed. Mere suspicion will not, however, be enough, particularly if it is vague and unsupported. Rather, the standard is one of “reasonable belief” of the facts giving rise to the relevant cause of action.

Where there is deliberate concealment (or fraud), the six-year period will not begin to run until such time as the claimant either discovered the concealment or ought reasonably to have discovered it. There must either be active and intentional concealment of a fact relevant to a cause of action, or at least intentional concealment by omission of a fact which the defendant knew they were under a duty to disclose. A fact relevant to the claimant’s cause of action refers to a fact without which the cause of action would be incomplete. It is not relevant that a defendant has concealed a fact which, if known, would merely strengthen a claimant’s case. Follow-on claims which are issued more than six years after the date of the underlying infringement decision (and depending on the context, the statement of objections preceding that decision – see Gemalto Holding and Thales DIS France v Infineon Technologies and ors [2022] EWHC 156) may be time-barred. However, defendants often argue that claimants either discovered or ought to have discovered any concealment earlier than the publication of the infringement decision, for instance, from the date of a press release relating to dawn raids or a statement of objections.

Claims Where Loss or Damage Occurred On or After 9 March 2017

Where the loss or damage occurred wholly on or after 9 March 2017, proceedings may not be brought before a court or tribunal after the end of a six-year limitation period. The limitation period begins on whichever is later – the day on which the infringement ceases, or the claimant’s “day of knowledge”. The latter is the day on which the claimant first knew, or could reasonably be expected to have known:

• the identity of the infringer;
• about the existence of the infringer’s behaviour;
• that the behaviour infringed competition law; and
• that the claimant itself had suffered loss or damage due to the infringement (paragraphs 17–26, Schedule 8A, CA 1998).

This period may also be suspended in various circumstances, including during an investigation by a competition authority or during a consensual dispute resolution process.

The typical timetable for an antitrust damages claim is around three to five years depending on a variety of factors, including the extent of disclosure, the number of witnesses and experts, whether the court or tribunal orders a stay, and whether applications are made for strikeout/summary judgment or for the determination of preliminary issues.

The status of related cases may also give rise to delays or applications for stays (eg, David Courtney Boyle & Edward John Vermeer v Govia Thameslink Railway Limited & Others [2021] CAT 38). Expedited trials may also be ordered in certain circumstances.

Procedures for bringing claims on a group or collective basis differ depending on whether such claims are brought in either the High Court or the CAT.

High Court

Collective claims have been brought in the High Court as so-called representative actions. CPR 19.6(1) allows a representative action to be brought by a claimant representing themselves and other claimants, where the group have the “same interest” and have opted in to the action. Representative actions are typically difficult to bring in private antitrust litigation. In Emerald Supplies Limited v British Airways plc [2009] EWHC 741 (Ch), the High Court struck out a representative action on behalf of both direct and indirect purchasers on the basis that the criteria for inclusion in the class depended on the outcome of the claim itself, and the direct and indirect purchasers would not all benefit from the relief sought by the claimant, because of the need for direct purchasers to pass on the overcharge to indirect purchasers in order for the latter to benefit from the damages awarded. The Court of Appeal upheld this decision, rejecting the claim as a means of engineering a class-action mechanism where one did not exist. The Court held that the “same interest” required a degree of certainty to constitute a class of persons capable of being represented by one person.

Group litigation orders (GLOs) under CPR 19.11 are available where one or more claims raise “common or related issues”. In practice, GLOs are rarely used in competition claims. However, Allsopp v Bayerische Motoren Werke AG [2023] EWHC 2710 provides a recent example of a GLO being used in competition litigation proceedings. In this claim, an application for a GLO was made on behalf of 41,225 out of approximately 125,000 claimants who had owned or leased BMW motor vehicles in the UK. The defendants manufactured, sold or leased these vehicles. The claimants alleged that the defendants were liable for the inclusion of prohibited defeat devices in certain diesel vehicles. The competition queries include determining whether the defendants participated in any breaches of A.101(a) TFEU or Chapter 1 of the CA 1998.

CAT

Collective actions have been available in the CAT since October 2015 for follow-on and standalone antitrust damages claims, following changes implemented by the Consumer Rights Act 2015 (CRA 2015). Claims may be brought on an opt-in or opt-out basis. The collective proceedings must be commenced by a person who proposes to be the representative in the proceedings. The CAT may authorise a claim where it is brought by a representative proposing to bring the claim on behalf of the class. The representative need not be a member of the class, if the CAT considers that it is just and reasonable for the representative to bring the claim in that capacity.

Collective proceedings will only continue if the CAT makes a collective proceedings order (CPO). The CAT will make a CPO if it is satisfied that the claims are eligible for inclusion in collective proceedings. To be eligible, the claims must raise the same, similar or related issues of fact or law. The CAT will also consider, among other factors, whether collective proceedings are an appropriate means for fair and efficient resolution of the collective issues, whether separate claims of the same or similar nature have already been commenced by members of the class, the class size and nature, whether it is possible to determine for any given person if they are a member of the class, and whether claims are suitable for an aggregate award of damages.

Collective actions have been available in the CAT since October 2015 for follow-on and standalone antitrust damages claims, following changes implemented by the Consumer Rights Act 2015 (CRA 2015). Claims may be brought on an opt-in or opt-out basis.

In making a CPO, the CAT must also decide whether the proceedings should be opt-in or opt-out. In O’Higgins v Barclays and ors and Evans v Barclays and ors [2023] EWCA Civ 876, the Court of Appeal stated that a powerful indicator towards a claim being certified as opt-out arises in scenarios where there would be no proceedings save on an opt-out basis. In addition, while the strength of the claim is usually to be a neutral factor in determining whether proceedings should be opt-in or opt-out, to the extent that it is taken into account, there needs to be a relevant connection between the strength of the claim and the decision made as to whether proceedings should go ahead on an opt-in or opt-out basis. The Court of Appeal also acknowledged that the existence of parallel individual or opt-in proceedings could be considered to demonstrate the feasibility of opt-in proceedings and clarified that whether or not the proposed class representative is a pre-existing body, such as a trade union, should not be taken into account. Non-UK residents must opt in to proceedings, even where the CAT has granted a CPO on an opt-out basis.

In Dr Sean Ennis v Apple [2024] CAT 58, the CAT gave judgment in an application for a collective proceedings order against Apple brought on behalf of app developers that have sold apps and paid an allegedly unfair commission to Apple in respect of in-app purchases on Apple’s iOS platforms. The defendant argued that the proceedings should not be brought on an opt-out basis. However, the CAT concluded that bringing proceedings on opt-in basis would not be in the interests of the class as a whole in this case: the fact that that the proceedings might be financially viable on an opt-in basis, did not overcome the impracticability of opt-in proceedings because most class members had relatively modest claims. The claim was certified on an opt-out basis as a result.

Non-UK residents must opt in to proceedings, even where the CAT has granted a CPO on an opt-out basis.

In the High Court, claims are based on the tort of breach of statutory duty of Chapters I/II of the CA 1998, and/or Section 2(1) of the European Communities Act 1972 (which imported into English law Articles 101 and 102 of the TFEU, to the extent applicable to pre-Brexit damage or conduct). Claims for damages before the CAT are based on Section 47A of the CA 1998 and/or Section 47B of the CA 1998. Section 47B forms the basis for collective actions, and allows both direct and indirect purchasers to bring claims for their losses on a collective basis in the Competition Appeal Tribunal

High Court

In the High Court, there is no equivalent in England and Wales of the US-style (opt-out) class-action procedure, nor is the certification process similar. In relation to representative proceedings in the High Court, it is necessary for the claimant representing others who have the same interest in the claim to show that the “same interest” test is satisfied. The Court of Appeal’s judgment in Emerald Supplies Ltd v British Airways plc [2010] EWCA Civ 1284 has shown that this will be difficult in the context of follow-on damages claims.

In relation to GLOs, an order can be made either of the court’s own motion or following a request from a claimant or defendant. GLOs are made where one or more claims raise “common or related issues”, a concept that is wider than the requirement that the persons have the “same interest” for representative proceedings.

CAT

The certification process for collective proceedings brought in the CAT has been heavily litigated. Under Section 47B of the CA 1998 (as amended by the CRA 2015), any collective proceedings may only proceed if the CAT makes a collective proceedings order. The CAT will make such an order if the person bringing the proceedings is someone it could authorise to act as the representative, and the CAT must also be satisfied that the claims are eligible for inclusion in collective proceedings. To be eligible, claims must raise the same, similar or related issues of fact or law and be suitable to be brought in collective proceedings. The collective proceedings must authorise the person who brought the proceedings to act as the representative; describe the class of persons whose claims are eligible for inclusion; and specify whether the proceedings are on an opt-in or an opt-out basis. The class of claimants must be comprised of those with eligible claims existing as at the date of the claim form and cannot include future claimants: see Alex Neill Class Representative Limited v Sony [2024] CAT 13, where the CAT ordered the CPR to amend the class definition so that the relevant period ended at the date of filing of the claim (rather than extending to the date of final judgment or settlement) to exclude any future claimants.

Since the 2020 Supreme Court judgment in Walter Merricks CBE v Mastercard Incorporated & Ors [2020] UKSC 51, the bar to certification has generally been considered to be relatively low, with the vast majority of cases being certified.

There have now been a small number of instances where a collective proceedings order has not been made. For example: (i) in the applications for collective proceedings against six water and sewerage undertakers, which the Tribunal rejected as the claim relied on alleged infringements of a statutory regime to which the only remedy was by way of an enforcement order by the UK’s water regulator; and (ii) in the application brought by Mr Rowntree to bring collective proceedings on behalf of songwriter members of the Performing Rights Society Limited.

Common-Law Jurisdiction Regime

For claims brought following 31 December 2020, and in respect of all defendants domiciled in jurisdictions outside the EU, the common-law jurisdiction regime applies, in which the English courts’ jurisdiction depends on the defendant being located within England or Wales, unless (on an application) it can be shown that another state’s courts are a more appropriate forum. Claimants can apply for permission to serve a defendant domiciled in another jurisdiction if they can show:

• that the claim has a reasonable prospect of success;
• that there is a basis for jurisdiction set out in the CPR; and
• that England and Wales is the proper place to bring the claim.

On 28 September 2020, the UK submitted a new accession instrument to the Hague Convention on Choice of Court Agreements. The UK is now bound by the Hague Convention in its own right rather than by virtue of its former EU membership; under the convention, EU member states must give effect to exclusive jurisdiction agreements in favour of the English courts.

The Brussels Regulation

For claims brought prior to the conclusion of the UK’s Brexit transition period, and where the defendant is domiciled in an EU member state, jurisdiction is governed by EU Regulation 1215/2012 (the Brussels Regulation). The Brussels Regulation contains various bases for determining the jurisdiction in which antitrust claims may be brought, including:

• where the defendant is domiciled;
• the place where an obligation under a contract was to be performed;
• in tort, the place where the harmful event occurred (the place where the damage was sustained or where the event giving rise to it took place);
• any jurisdiction agreement;
• whether a party submits to a jurisdiction; and
• the jurisdiction of any related actions.

Standard and Specific Disclosure

Disclosure generally takes place once particulars of the claim, defence, and any replies have been served. If standard disclosure is ordered, parties to the litigation must search for and disclose all documents in their control on which they rely, and documents that adversely affect their own case, adversely affect another party’s case, or support another party’s case. Specific disclosure is commonly ordered in antitrust claims, requiring the disclosure of specific documents or categories of documents. The CAT Rules are supplemented by the CAT Practice Direction relating to Disclosure and Inspection of Evidence 2017. An order for disclosure may also be made requiring non-parties to disclose documents if the disclosure is likely to support the case and is necessary to dispose of the claim fairly or to save costs.

Pre-Action Disclosure

This may be ordered before a claim is issued. Parties are encouraged to agree to exchange documents pre-action in order to seek to resolve legal disputes before proceedings are commenced. Pre-action disclosure may be ordered where the documents or classes of documents to be disclosed would fall within the test for standard disclosure, and the court believes that pre-action disclosure is desirable to dispose fairly of anticipated proceedings or to assist in the resolution of the dispute without proceedings or at a lower cost. Applications for pre-action disclosure that are overly broad will be refused, so potential claimants should carefully consider the scope of any requests they make.

With the introduction of the Disclosure Practice Direction 57AD (formerly the Disclosure Pilot) in the business and property courts of England and Wales, there has been a change to the disclosure regime; however, the Direction does not currently apply to competition law claims, unless otherwise ordered.

See 6.3 Leniency and Settlement Agreements in relation to leniency statements and settlement submissions.

Restriction on Documents

There is a general restriction on parties not to use documents received during disclosure other than for the purpose of the litigation. However, if those documents are referred to in open court, then this protection may be lost. Confidential and irrelevant material may be redacted, although significant redaction may be resisted by the court. Confidential material may also be protected by way of a “confidentiality ring”, in which only specified persons will be permitted to access these documents.

Documents may be withheld from inspection on the basis that they are protected by legal professional privilege, which falls into two broad categories:

• legal advice privilege; and
• litigation privilege.

Legal Advice Privilege

Legal advice privilege protects communications which are:

• confidential;
• between a client and lawyer; and
• made for the dominant purpose of giving or receiving legal advice.

Confidentiality is key – if a communication has become public, been shared with a third party (on a non-limited waiver basis), or been circulated widely, it will no longer be privileged.

The communication must be between lawyer and client, for the purposes of which a “lawyer” includes both external and in-house counsel, who may be qualified in any jurisdiction. The definition of a “client” for the purposes of privilege includes those authorised to give and receive legal advice (following Three Rivers No 5), rather than all employees within the undertaking. In SFO v ENRC [2018] EWCA Civ 2006, the Court of Appeal held that communications between an employee and the corporation’s lawyers could only be privileged if that employee was tasked with seeking and receiving advice on behalf of the corporation. The dominant purpose of the communication must be the giving or receiving of legal advice (R (Jet2) v CAA [2020] EWCA Civ 35).

Litigation Privilege

Litigation privilege applies to confidential communications between a lawyer and client and communications between a lawyer or client and a third party which come into existence after litigation is contemplated. The communication must be for the sole or dominant purpose of:

• obtaining or giving legal advice in relation to the litigation;
• obtaining evidence to be used in litigation; or
• obtaining information that may lead to the obtaining of evidence.

In Tesco Stores v OFT [2012] CAT 6, the CAT found that proceedings were sufficiently adversarial, at least by the time that the OFT had issued a statement of objections. In SFO v ENRC [2018] EWCA Civ 2006, the Court of Appeal found that where the Serious Fraud Office had made the prospect of criminal prosecution clear to the defendant and lawyers had been engaged, there was a basis for concluding that criminal prosecution was in reasonable contemplation.

Leniency statements and settlement agreements are protected from disclosure under Part 6 of the 2017 UK Regulations implementing the EU Damages Directive.

Claims Issued On or After 9 March 2017

For claims issued wholly on or after 9 March 2017, the CA 1998 prohibits a court or tribunal from making a disclosure order in respect of a settlement submission that has not been withdrawn, or a cartel leniency statement. In addition, a competition authority’s investigation materials are not admissible in evidence in competition proceedings at any time before the competition authority has closed the investigation, unless a party obtains them lawfully and by other means than from the authority’s file.

Claims Issued Prior to 9 March 2017

For cases that began prior to 9 March 2017, the position is governed by case law. The ECJ held, in Pfleiderer v Bundeskartellamt, that EU law allows member state courts and tribunals to determine when materials may be disclosed. In National Grid Electricity Transmission plc v ABB Ltd [2012] EWHC 869 (Ch), the High Court held that a number of factors were relevant in the balancing exercise between disclosure and confidentiality of leniency and investigation materials. Firstly, the Court considered whether such disclosure would increase the leniency applicants’ exposure to liability or whether it would put these parties at a relative disadvantage compared with the parties that did not co-operate with the investigating authority. Secondly, the Court considered whether the potential effect of a disclosure order would deter potential leniency applicants in future investigations. Thirdly, the Court considered whether the disclosure sought was proportionate in the circumstances. The EC intervened, making submissions against the disclosure of leniency documents. The judge decided that the question of relevance needed to be determined on the basis of each document and ordered only limited disclosure of those documents requested.

High Court

Factual evidence in the High Court may take the form of documents or witness evidence. Witness evidence is provided in witness statements (which are exchanged in advance of trial) and oral evidence given at trial. A witness may be cross-examined and re-examined at trial on the basis of their witness statement. The weight given to witness evidence will depend on the credibility of the witness, as well as the other circumstances of the case. A party wishing to secure the evidence of a witness present within the jurisdiction, in the form of oral evidence at trial, can also issue a witness summons under CPR 34.31.

In the Business and Property Courts, Practice Direction 57AC applies to trial witness statements. The requirements include that the trial witness statement must contain only evidence as to matters of fact that need to be provided at trial by the evidence of the witness in relation to an issue of fact to be decided at trial and must set out only matters of fact which the witness has personal knowledge which are relevant to the case.

CAT

The CAT proceeds on the basis that it will “be guided by overall considerations of fairness rather than technical rules of evidence” (Argos v OFT [2003] CAT 16). The CAT has the general power to control the evidence placed before it by giving directions as to the issues on which it requires evidence, the nature of the evidence it requires, and the way in which the evidence is to be placed before it. The CAT may also dispense with hearing oral evidence if a written witness statement suffices, or it may limit cross-examination of witnesses. The CAT also has the power to issue a summons requiring a person in the UK to attend as a witness before the CAT and produce documents.

The CAT’s 2021 practice direction (Practice Direction 2/2021) on witness statements for trial provides that a trial/appeal witness statement must contain only evidence as to matters of fact that need to be proved at trial by the evidence of witnesses in relation to one or more of the issues of fact to be decided at trial, and to such matters that the witness would be asked by the relevant party to give, and the witness would be allowed to give, in evidence-in-chief if they were called to give oral evidence. In addition, a witness statement must set out only matters of fact of which the witness has personal knowledge that are relevant to the case, and must identify by list what documents, if any, the witness has referred to or been referred to for the purpose of providing the evidence set out in their trial/appeal witness statement. Both the witness and the relevant legal representative must sign a statement of compliance to state they have complied with this practice direction.

Expert evidence in the High Court may only be given with the permission of the Court and follows the exchange of witness statements from the witnesses of fact. The expert has a duty to the court overriding any obligation to the instructing party. Expert evidence is normally in the form of a written report followed by written questions to the expert and possible cross-examination at trial. The courts may request that experts prepare joint statements which seek to clarify the areas of agreement and disagreement in advance of the trial. The court may also order the appointment of a single joint expert (though this is less common in antitrust claims).

There have also been cases where courts have ordered that expert evidence be given concurrently, also known as “hot-tubbing”, which is typically judge-led and results in more limited time for cross-examination by the parties (recently in National Grid Electricity Transmission plc v ABB Ltd).

The CAT also has similar rules for dealing with expert evidence, and may also appoint its own expert.

Assessment of Damages

Damages are awarded on a tortious basis. ECJ case law requires compensation to be available not only for actual loss but also for lost profit and interest. There is a rebuttable presumption, following the implementation of the EU Damages Directive, that cartels cause harm.

In BritNed Development Limited v ABB AB and ABB Limited [2019] EWCA Civ 1840, the Court of Appeal found that damages can only be awarded on a compensatory, rather than punitive basis. In the High Court’s earlier judgment, it had found that damages should be awarded based on savings ABB was said to have made, rather than the loss suffered by BritNed through paying an inflated price due to the competition law infringement. The Court of Appeal found this was an error of law and that the High Court’s decision did not comply with the compensatory principle in English law. The Court of Appeal did, however, agree with the High Court that claimants must show actionable harm, which required demonstrating a causal link between the infringement and the damages, generally through the “but for” test of causation. The elements of the cause of action have to be proved on the balance of probabilities, and damages awarded in order to put the claimant in the position it would have been in had the tort not been committed. A claimant’s inability to prove the exact sum of its loss was not a bar to recovery. The assessment of damages would often involve some estimation and assumption, and the court could take a broad-brush approach based on an understanding of the context in which the harm was suffered. However, the assessment had to be grounded in the evidence.

For claims where the loss or damage suffered was wholly on or after 9 March 2017, under paragraph 36, Schedule 8A of the CA 1998 (as amended), a court or tribunal may not award exemplary damages in competition proceedings (although, note that the UK government has announced plans to give the CAT discretion to award exemplary damages for breaches of competition law (aside from in collective proceedings)).

For claims where loss or damage was before 9 March 2017, punitive and exemplary damages are available in certain limited circumstances in England and Wales. Section 47C of the CA 1998 also prevents the CAT from awarding exemplary damages in collective proceedings.

“Passing-On” Defences

Damages awarded to a claimant as a purchaser of a cartelised product may be reduced if the defendant can prove that the overcharge was passed on to the claimant’s own customers.

In Sainsbury’s v Mastercard [2016] CAT 11, the CAT held that the pass-on defence is only available for identifiable increases in prices by a firm to its customers. The CAT also held that the defendant must show on the balance of probabilities that there is another class of claimant, to whom the overcharge has been passed on, in the absence of which a claimant’s damages should not be reduced. The Court of Appeal upheld the CAT’s finding that Mastercard’s defence failed because no identifiable increase in retail price had been established, let alone one causally connected to the UK Multilateral interchange fee. In an appeal from the Court of Appeal, the Supreme Court held that the Court of Appeal erred insofar as it required a greater degree of precision in the quantification of pass-on from the defendant than from the claimant. Once a defendant has raised pass-on, there is a heavy evidential burden on the claimant to provide evidence as to how they have dealt with the recovery of their costs in their business. Most of the relevant information about what a claimant has done to cover its costs will be exclusively in the hands of the merchant itself, and the claimant must produce evidence in order to forestall adverse inferences being taken against it by a court applying the compensatory principle. The Supreme Court concluded that the law does not require unreasonable precision in the proof of the amount of the prima facie loss which the merchants have passed on to suppliers and customers.

For claims where the loss or damage suffered from an infringement took place wholly on or after 9 March 2017, the claimant is presumed (subject to rebutting evidence) to have proved that the overcharge or underpayment was passed on if:

• the defendant infringed competition law;
• there was an overcharge or underpayment as a result of the infringement; and
• the product or service was provided to the customer by the claimant.

This was applied by the CAT in Royal Mail Group Limited v DAF Trucks Limited and Others, BT Group PLC and Others v DAF Trucks Limited and Others [2023] CAT 6 in which the CAT clarified that the legal test for causation in relation to a pass-on defence required the defendant to prove a direct and proximate causative link between the overcharge and any increase in prices by the claimants.

In the case of Granville Technology Group Limited v Chunghwa Picture Tubes Ltd, LG Display Co. Ltd [2024] EWHC 13, the Court addressed the issues of overcharge and pass-on in the context of a cartel's influence on the prices of Liquid Crystal Display (LCD) panels. The claimants, manufacturers and sellers of desktop PCs with monitors and notebooks, alleged that due to the cartel's activities, they paid inflated prices for LCD panels, constituting an overcharge. They sought to recover this overcharge as damages for breach of statutory duty. While it was undisputed that an overcharge occurred, the extent of it was contested. The defendants argued that the claimants had passed on any price increase to their customers, negating any claim of loss.

In assessing the overcharge, the court found it to be necessary to assess what would have happened had the infringement not occurred, leading to the conclusion that the overcharge rates attributable to the cartel were 8% for monitors, 4% for notebooks and 14% for TVs. When examining the pass-on to downstream customers, the court found that, in line with compensatory principles, any loss that had been passed on was not compensable. The court estimated that 65% of the overcharge was likely passed on, considering market competitiveness and the variable pass-on rates during the relevant period. Despite this, the court recognised that the claimants had suffered a significant loss of profit due to reduced sales, which they successfully demonstrated was a consequence of passing on the overcharge to their customers.

Interest

The English courts have discretion to order pre-judgment interest on damages, awarded at the claimant’s borrowing rate or a fair commercial rate. If the claimant can show that it has had to pay interest on the debt as a result of its principal losses, the claimant may obtain compound interest. The CAT may also order that interest be payable on damages for any part of the period between the date when the action arose and the date of decision of the award for damages. In Royal Mail Group Limited v DAF Trucks Limited and Others, and BT Group PLC and Others v DAF Trucks Limited and Others [2023] CAT 6, the CAT followed the approach in Sainsbury’s v Mastercard [2016] CAT 11 and awarded compound interest. The CAT noted that a claim for compound interest can better reflect a claimant’s actual interest losses and that it is perhaps surprising that compound interest is not ordered more often.

It is generally understood that defendants in a cartel action are jointly and severally liable. Article 11 of the EU Damages Directive also requires member states to ensure that undertakings which have infringed competition law through joint behaviour are jointly and severally liable for the harm caused by the infringement of competition law. There is a statutory exception to this position for small and medium-sized enterprises set out in Part 3 of Schedule 8A of the CA 1998, for infringements of competition law which took place on or after 9 March 2017.

For claims where the loss or damage suffered as a result of a cartel took place wholly on or after 9 March 2017, an immunity recipient is not liable (either alone or jointly) to pay damages as a result of the cartel infringement, subject to certain exceptions (paragraph 15, Schedule 8A, CA 1998), namely if:

• the claimant is unable to obtain full compensation for the loss or damage from other undertakings involved in the cartel infringement;
• the claimant acquired (or provided) a product or service that was the object of the cartel infringement directly or indirectly from the immunity recipient (or to the immunity recipient);
• the claimant acquired a product or service containing or derived from a product or service that was the object of the cartel infringement indirectly from the immunity recipient; or
• the product or service that was the object of the cartel infringement contained or was derived from a product or service provided by the claimant.

The principle of joint and several liability is also subject to certain modifications in the context of settlements where the infringement of competition law occurred on or after 9 March 2017.

In England and Wales, the Civil Liability (Contribution) Act 1978 allows for contribution between persons who are jointly or severally, or both jointly and severally, liable for the same damage, either in the same or new proceedings. The court may determine how liability between defendants is apportioned. In cases of cartel infringements, the approach that the courts will take to contributory liability is unclear; the court may, for instance, apportion according to perceived cartel member culpability, and/or based on volume of sales. A defendant can still bring a claim for contribution against another party even when it has settled its dispute with the claimant.

Where the loss or damage in a claim took place wholly on or after 9 March 2017, the amount of recoverable contribution must be determined in light of the parties’ relative responsibility for the whole of the loss or damage caused by the infringement, taking into account any damages paid by the other person in respect of the loss or damage, in accordance with a settlement between an infringer and a claimant. This is likely to take account of the volume of sales of the parties.

Injunctions are available both in the High Court and in the CAT.

High Court

Claimants can seek injunctions in the High Court for ongoing or anticipated breaches of competition law. These may be prohibitory, mandatory, or quia timet (relating to future conduct). The applicant must show:

• a good, arguable case;
• that damages would be inadequate to remedy its losses; and
• that the balance of convenience favours ordering the injunction.

Where an interim injunction is sought, a claimant must give a cross-undertaking in damages to cover any loss suffered by the defendant if the former were to lose the substantive case which follows. The High Court can also award security for costs.

The timing of an application is a critical issue. In AAH Pharmaceuticals v Pfizer Limited & Unichem Limited [2007] EWHC 565 (Ch), the last-minute nature of the application and the complexity of the analysis required to establish whether Pfizer’s actions were anti-competitive caused the Court to refuse the wholesalers’ application. Although injunction applications may be made without notice, this is only in exceptional circumstances which must be justified to the court. In such an ex parte application (ie, made on a without-notice basis), the applicant bears the burden of full and frank disclosure to the court and, in the absence of the respondent party, must not withhold evidence which is adverse to its case.

CAT

The CRA 2015 introduced powers under which the CAT may grant injunctions in individual claims or collective proceedings. An injunction granted by the CAT has the same effect as an injunction granted by the High Court, and the CAT must apply the same principles as outlined above. Failure to comply with an injunction allows the CAT to certify the matter to the High Court, which may deal with that person as if they were in contempt. An application for an interim injunction can be made without notice if it appears to the CAT that there are good reasons for not giving notice which must be stated as part of the evidence in support of the application.

Alternative dispute resolution (ADR) is available and encouraged by the courts in England and Wales, but is not mandatory. Antitrust disputes are arbitrable if the claim alleging an antitrust infringement falls within the ambit of an arbitration clause. The courts have held that antitrust claims are arbitrable. In Microsoft Mobile v Sony [2017] EWHC 374 (Ch), the High Court considered the application of an arbitration clause in a tortious claim arising from allegations of anti-competitive conduct and determined that the claim could be stayed under Section 9 of the Arbitration Act 1996. This approach was confirmed in Gazprom Export LLC v DDI Holdings Ltd [2020] EWHC 303 (Comm).

Damages-Based Agreements (DBAs)

DBAs are available, under which lawyers can agree to accept a share of the clients’ winnings, capped at 50%. DBAs must be on a no win, no fee basis. DBAs are not available in opt-out collective proceedings (as confirmed in Paccar Inc and Ors v Road Haulage Association Limited and UK Claims Limited [2023] UKSC 28).

Litigation Funding Agreements (LFAs)

Following the Supreme Court’s judgment on 26 July 2023 in Paccar Inc and Ors v Road Haulage Association Limited and UK Claims Limited [2023] UKSC 28, LFAs, in which the funder’s return is a share of damages ultimately awarded to the claimant, are now also categorised as DBAs and are therefore not enforceable if they do not meet the requirements set out in the applicable regulations, such as capping the share of winnings at 50% and being on a no win, no fee basis. LFAs have now been updated to work around this ruling, with provisions such as recovering a multiple of the funds committed being applied. In March 2024, the UK government announced the Litigation Funding Agreements (Enforceability) Bill, which sought to reverse the decision of the judgment on third-party litigation funding (R (on the application of PACCAR Inc) v Competition Appeal Tribunal [2023] UKSC 28). While this bill was ultimately not passed prior to the 2024 General Election, the Civil Justice Council 2025 review has advised that this decision should be reversed, and so we await to see if legislative reform will be introduced to address this.

Conditional Fee Arrangements (CFAs)

CFAs, in which lawyers act on a “no win, no fee” basis, with provision for a “success fee” uplift in the event of a successful outcome, are available in England and Wales. CFAs must be in writing and the percentage uplift cannot be more than 100% of the lawyer’s normal fees. The uplift is no longer recoverable from the losing party in most cases. If the CFA was entered into before 6 April 2016, then the uplift may be recoverable from the losing party. Following Paccar Inc and Ors v Road Haulage Association Limited and UK Claims Limited [2023] UKSC 28, if the funder’s return is a share of damages ultimately awarded to the claimant, CFAs will now also need to comply with the requirements of a DBA.

Third-Party Funding

Third-party funding by a professional litigation funder is also available in competition cases. The Court of Appeal has held that professional funders should be liable to pay the costs of opposing parties, capped at the amount of funding they provided. Following Paccar Inc and Ors v Road Haulage Association Limited and UK Claims Limited [2023] UKSC 28, if the third-party funder’s return is a share of damages ultimately awarded to the claimant, these arrangements will now also need to comply with the requirements of a DBA.

Insurance

Legal expenses insurance, or after-the-event insurance, is also available to cover costs, although such insurance is normally expensive.

High Court

Costs follow the event

The general rule in the High Court is that costs follow the event, namely, that the unsuccessful party pays the reasonable costs of the successful party (CPR 44.2). However, the courts have general discretion in awarding costs, and will have regard to all the circumstances of the case, including the conduct of the parties, whether a party was partially successful, and any payment into a court or settlement offer that is drawn to the court’s attention. Note that even where a costs order is made, the successful party is generally only likely to recover around two-thirds of its costs.

Costs orders against third parties

In exceptional cases, a successful party may seek a costs order against a third party, for example, if a third party has helped to fund litigation on behalf of the losing party. However, following Arkin v Borchard Lines Limited [2005] EWCA Civ 655, it is necessary to distinguish between “pure funders” (who personally have no interest in the litigation and do not stand to benefit from it) and professional funders. The Court in Arkin held that costs orders would not be made against pure funders, but against professional funders costs orders may be made to the extent of the funding provided.

Offers to settle

Offers to settle can also be made under CPR Part 36, which may have certain costs consequences. For example, a defendant can make a Part 36 offer, and if the claimant accepts, that ends the litigation. However, if the claimant rejects the offer and succeeds at trial but is awarded less at trial than the amount of the offer, the claimant will generally have to pay the defendant’s costs from the 21st day of the offer. A claimant can also make an offer under Part 36. If the defendant refuses the offer and the claimant recovers more at trial, the court can order the defendant to pay a 10% uplift on that sum and interest on all or part of the sum recovered.

CAT

Factors determining costs

CAT Rule 104 provides that the CAT may, at its discretion, make any order it considers fit in relation to the payment of costs. In contrast to the provisions in relation to the High Court, in the CAT there is no general rule that costs follow the event. However, the CAT Rules provide a number of factors that the CAT may take into account when determining the amount of costs. These factors are set out in CAT Rule 104(4) and include:

• the conduct of all parties in relation to the proceedings;
• any schedule of incurred or estimated costs filed by the parties;
• whether a party has succeeded in part of its case, even if that party has not been wholly successful;
• any admissible offer to settle that is drawn to the CAT’s attention, and that is not a settlement offer to which cost consequences apply;
• whether costs were proportionately and reasonably incurred; and
• whether costs are proportionate and reasonable in amount.

The general approach in the CAT is that the appropriate starting point is that the successful party should be awarded its costs (Albion Water v Dwr Cymru Cyfngedig [2013] CAT 16). However, the CAT acknowledges that a balance must be struck between ensuring that costs awards do not undermine the effectiveness of the competition regime whilst ensuring a just result for both parties (CMA v Flynn Pharma [2020] UKSC 12).

Offers to settle

The CAT Rules also include specific cost consequences relating to the acceptance or rejection of a settlement offer that are similar to those applicable in the High Court under the rules on offers to settle in CPR Part 36. Under the CAT Rules, an offer to settle is labelled a “Rule 45 Offer”.

Costs orders

In addition, CAT Rule 57(1)(d) states that if any party fails to comply with any direction, the CAT may order that the party (or its representative) be subject to an order for costs as the CAT sees fit.

In June 2016, in Socrates Trading Limited v The Law Society of England and Wales, the CAT decided to exercise its powers under Rule 58(2)(b) to cap the level of recoverable costs in the case.

Judgments of the CAT and the High Court may be appealed to the Court of Appeal, provided the permission of the lower court or the Court of Appeal has been obtained. Appeals are typically only permitted on points of law. They can be made either by a party to the proceedings or by someone who has sufficient interest in the matter. A further appeal from the Court of Appeal to the Supreme Court is possible, again provided permission is granted either by the Court of Appeal or the Supreme Court.

This year there have been a number of key developments in collective action proceedings before the Competition Appeal Tribunal. Key developments are outlined below.

• Certification: In 2025 the Tribunal issued the first three judgments refusing certification of collective proceedings. The first of these was in the case of Christine Riefa Class Representative Limited v Apple Inc. & Others [2025] CAT 5, where the Competition Appeal Tribunal refused the application for certification on the basis that the Tribunal did not consider the Proposed Class Representative (PCR) satisfied the authorisation conditions to be a Class Representative. The second was in a case brought against six water and sewerage undertakers [2025] CAT 17, where the Tribunal rejected the claim as it relied on alleged infringements of a statutory regime to which the only remedy was by way of an enforcement order by the UK’s water regulator. The third was in Rowntree v Performing Right Society Limited and PRS [2025] CAT 49 on grounds including that there was not a credible methodology to assess damages.
• First Liability Judgment: December 2024 saw the first liability judgment in collective proceedings in the Le Patourel judgment [2024] CAT 76. The CAT found that, while BT was dominant in the relevant market of standalone fixed voice services and its prices were excessive, the prices charged were not unfair. As a result, BT had not breached competition law and no damages were awarded. The claimants were refused permission to appeal from the CAT [2025] CAT 10 and, in July 2025, the Court of Appeal refused permission to appeal.
• Merricks Settlement: In February 2025, the CAT gave an oral ruling approving the largest proposed settlement of a collective action so far in the collective action brought against Mastercard by Merricks. The claimants originally sought damages of GBP14 billion plus interest, bringing it to just under GBP20 billion claimed. The claim faced a number of hurdles along the way, with issues around limitation, causation and pass-on. In December 2024, a settlement agreement was reached. The litigation funder objected to the settlement. It argued that the settlement sum was too low and that Mr Merricks should have pressed on, seeking to exert greater pressure on Mastercard to pay a higher amount. Despite this, the CAT found it to be just and reasonable. In May 2025, the Tribunal ruled on the proposed distribution of the GBP200 million. The Tribunal approved the proposal of Mr Merricks and Mastercard that: (i) GBP100 million would be ring-fenced for class members; (ii) GBP46 million would be ring-fenced as a minimum return to the funder (roughly equating to its deployed capital); and (iii) the remaining, depending on class take-up, would enable the funder a profit return, with the rest paid to charity. Despite strenuous objections from the funders, the CAT commended the plan which it found sought to achieve the maximum take-up of a reasonable sum by class members. 
• Funding: In March 2024, the UK government announced the Litigation Funding Agreements (Enforceability) Bill, which sought to reverse the decision of the judgment on third-party litigation funding (R (on the application of PACCAR Inc) v Competition Appeal Tribunal [2023] UKSC 28). While this bill was ultimately not passed prior to the 2024 General Election, the Civil Justice Council 2025 review has advised that this decision should be reversed, and so we await to see if legislative reform will be introduced to address this.

Beyond the collective proceedings regime, the antitrust litigation regime continues to develop strongly. For example, a critical judgment developing this regime was issued in July 2025 in the Court of Appeal in Phones 4u Limited v EE Limited and others [2025] EWCA Civ 869 which provided guidance on how competition law should deal with passive recipients of anti-competitive approaches by competitors, and the proper approach to determining related causation issues.