Class actions in the UK have grown dramatically in volume and scale, beginning to rival some of the largest U.S. cases in both the number of claims and potential damages sought. Recent years have witnessed a notable shift towards opt-out class actions—where potential claimants are automatically included unless they choose to opt out—marking a major evolution in collective litigation within the UK and across Europe. In 2023 alone, Europe saw a record 133 class action claims, reflecting a 10% increase from the previous year and a staggering 93% rise since 2019. Notably, for the first time, opt-out class actions outnumbered opt-in actions across Europe, with the UK as the highest-risk jurisdiction, encompassing over 540 million class members and approximately €145 billion in claims by the end of 2023.

This surge has been fueled by several factors. A landmark UK Supreme Court decision in 2020 fundamentally lowered the threshold for certifying mass claims, allowing collective actions to proceed even without the need for precise individual loss assessments. This was epitomised by the Merricks v Mastercard case, which saw a class of 46 million UK consumers seek over £14 billion in damages, setting a precedent that has reverberated throughout UK litigation circles. Coupled with the increased use of litigation funding, these changes have made bringing large, complex claims financially viable and more attractive.

The UK has seen a particular proliferation in high-value tech-related class actions. Over 20 significant claims are currently underway against major technology companies, with aggregate claims exceeding £30 billion. These encompass sectors such as digital advertising, app store monopolies, and online marketplaces. The rise in these claims partly reflects broader trends in the application of opt-out regimes and stronger antitrust enforcement, as well as the technological sophistication involved in dissecting alleged anti-competitive behaviour.

Key to the success of these cases is the involvement of forensic and economic experts. Their role is critical from the very outset: identifying and preserving relevant digital evidence—transaction logs, user data, pricing information—and developing rigorous economic models to prove causation and estimate aggregate damages at a class-wide level. For example, in recent high-profile carriage disputes, expert teams have employed cutting-edge methodologies such as re-running platform algorithms stripped of alleged abusive behaviours, combining competition economics with data science and machine learning to present compelling assessments of harm. Courts have shown an increasing willingness to engage with such advanced and innovative approaches when they offer improved insights over traditional econometric methods.

The involvement of these experts is vital throughout the litigation lifecycle—from pre-action data mapping and early certification phases, where establishing commonality of harm is crucial, to detailed discovery, econometric testing, and expert testimony at trial or settlement. Experts also play a pivotal role in “stress-testing” the opposing side’s case, uncovering weaknesses or alternative explanations such as market forces unrelated to alleged misconduct that may limit or negate claimed damages. This dynamic underscores the complex interplay of data science, economics, and law in modern digital economy disputes.

The rise of such class actions is not without controversy. Critics, including some of the defendants, argue that these lawsuits often benefit lawyers and funding entities disproportionately, rather than delivering meaningful redress to consumers or businesses. However, proponents maintain that collective actions serve a vital role in holding powerful digital firms accountable, deterring anti-competitive conduct, and providing a practical route for victims—often dispersed and financially unable to litigate individually—to seek justice.

Beyond litigation strategy, early engagement with forensic and economic experts signals a proactive approach to risk and compliance management. For defendants, this can support internal investigations, regulatory disclosures, and demonstrate transparency, while for claimants, it can help shape litigation strategies to align with evolving regulations such as the EU Digital Markets Act and the UK Digital Markets, Competition and Consumers Act. Preservation of digital evidence before it is lost or altered is critical in these fast-moving tech environments, and early expert input often determines the difference between a robust case and one vulnerable to key evidentiary challenges.

As class actions continue to grow in size, complexity, and number, legal teams increasingly rely on cross-disciplinary collaboration and technological innovation to build and defend cases. Harnessing the combined power of forensic data analysis, economic expertise, and legal acumen is now indispensable for navigating this rapidly evolving landscape, both in the UK and across Europe. By avoiding silos and emphasising early, coordinated expert involvement, parties engaged in digital economy class actions stand better prepared to withstand rigorous legal, regulatory, and commercial scrutiny.

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Source: Noah Wire Services