Opt-out collective action: expanding beyond the Commercial Court?

Merricks vs Mastercard was a pivotal case is determining certification of collective actions. But with Evans vs Barclays Bank, the test for determining whether to certify on an opt-out basis have been further clarified, marking one of the most significant developments in the regime.

In the context of collective action, opt-out claims are still restricted to the Competition Appeal Tribunal (CAT). Given its relative success, the Law Commission has been tasked with collecting evidence before extending opt-out provisions to other courts.

Any such extension would not simply be a procedural extension though. It raises fundamental questions about access to justice, litigation funding and corporate exposure.

Because opt-out collective action is only available in the Competition Appeal Tribunal, many claims end up being “shoehorned” into competition law. This is true even when the claim is inherently commercial in nature.

To prevent ineligible certification, the CAT operates as a gatekeeper. As confirmed by the Supreme Court, the CAT has broad discretion in certification decisions, filtering weak or inappropriate opt-out claims before they are tried.

Achieving opt-out certification is difficult by design. The weaker the case, the less justification there is for certification. And even if an action does survive strike-out, it may still be too weak for a full opt-out certification.

From what our research contacts tell us, demand for group litigation is increasing in the face of judicial caution and strict filtering. The system is simultaneously overburdened and restrictive.

Supreme Court rulings contain a very clear instruction: opt in should generally be preferred if it is practicable. This helps to explain the high bar for certification.

In the past, claimants have argued that opt in cases are not viable without aggregation (because of costs for instance). The Supreme Court has ruled that this is not a ‘trump card’ for certifying opt-out.

Instead, certification depends on the strength of the claims and the practicality of participation. This means that many borderline cases remain excluded from opt-out treatment.

So while many practitioners would like to see opt-out provisions extended to the Commercial Court, they would still likely remain exceptional rather than the default.

The current model is under significant pressure. This is mostly because the CAT is designed for competition claims, but an increasing number of non-competition group claims are being funnelled through the court.

To achieve this redirection, claims are being strategically framed to fit CAT jurisdiction. However, this goes on to create artificial legal arguments and inefficiencies in certification that overload the system.

Our research shows that group litigation is now the dominant trend in commercial disputes. Litigation funding and institutional investor participation appear to be the driving factors behind this trend. Opt-out reform has moved from conceptual to reality as cases are already happening in practice.

The Supreme Court specifies that the CAT regime must facilitate redress for claimants at the same time as protecting defendants from oppressive litigation. This balance rejects a claimant-first approach, because access to justice is not determinative. The starting point in any opt-out collective action is neutral.

Preventing weak opt-out claims is essential to preventing claimants from exercising undue leverage on defendants. As funders seek large aggregate claims. The high bar for certification is essential, particularly as there have been indications of judicial concern regarding settlement pressure and strategic litigation behaviour.

Balancing these competing requirements has made the extension of opt-out collective actions a live policy conflict, rather than a question of “just” procedural reform.

Opt-out fundamentally changes the economics of a group action. Allowing automatic class inclusion immediately results in larger damage pools and higher funding returns.

Taking advantage of this, funders are already highly active in collective claims. Unsurprisingly, claims are increasingly built around scale, rather than the merit of the case itself. Under the current regime, the CAT acts as a check against weak but well-funded claims.

For some litigation funders, opt-out collective action may be seen as a gateway to mass claims at scale. However, as things stand, the Supreme Court framework imposes strict structural limits on expansion. Opt-out is very much a conditional certification rather than an automatic entitlement for any incoming case.

Even if the UK moves towards a hybrid model that mixes large institutions and small claimants in a class action, it is unlikely we will see a total replication of the US-style litigation environment. Why? Because even if collective actions increase, the courts will retain stricter judicial control, particularly when considering certification.

Collective actions are already shifting beyond the competitions arena – and could go further still depending on the results of the Law Commissions investigation into formalising opt-outs for other courts.

Until then, the Supreme Court has established clear guidelines regarding certification. The UK is moving towards a more collective litigation model, but it will continue to be defined by judicial restraint, policy balance, and strategic complexity.

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