As discussed in our recent thought leadership exploring the current data breach claims landscape, a number of judgments have seen the courts take clear action to limit the efficacy of breach-related class actions and data claims involving multiple causes of action.

The Supreme Court in the representative action of Lloyd v Google dismissed the claim on the basis that there was no 'same interest' established by the claimants, despite the representative claimant submitting that the value of the individual claims was limited to the same monetary figure. Efforts to circumvent a comparable outcome in Prismall v Google by reformulating a similar representative claim to one of misuse of private information were also unsuccessful.

The courts have also taken a robust view of whether trivial data breach claims merit damages at all. Combined with fixed recoverable costs, pursuing data breach claims has become financially challenging for claimant law firms.

Claimants and their representatives are therefore likely to seize upon any routes for mass claims which potentially avoids the costs and complications of the representative and group litigation order processes or limits the need to issue individual claims with the associated court fees and restrictions on costs recovery. The courts' permissive approach to the use of the 'omnibus' Claim Forms has therefore increased in popularity when it comes to volume mass data breach claims.

As a relatively novel approach however, a close eye must be kept on how the courts respond to claims seeking to use this method, and possible limits. What is also clear is that further guidance from the Civil Procedure Rules Committee is expected in the coming months.

The omnibus Claim Form: a condensed history

The ‘omnibus' Claim Form is shorthand for a type of Claim Form permitted by CPR 7.3. Under this provision, claimants are permitted “use a single Claim Form to start all claims which can be conveniently disposed of in the same proceedings.”

The process is flexible, meaning that although cases are managed together, "test or lead cases may, or may not, be identified and tried to determine common issues. They may be split apart to determine preliminary liability issues in batches or later to determine individual quantum or remedies."¹ As noted by the High Court recently, the process is still developing.

So, for those considering bringing a claim via the omnibus Claim Form route, when are claims capable of being 'conveniently disposed of in the same proceedings'?

There have been a number of cases considering the suitability of the use of omnibus Claim Forms in certain types of actions. In Morris v Williams & Co Solicitors², the Court of Appeal undertook a lengthy analysis of case law (including the case of Abbott v Ministry of Defence³) and other authorities to understand the test for satisfying rule 7.3.

Handing down lead judgment, the Master of the Rolls, considered rule 7.3 alongside CPR 19.1 which allows for "any number of claimants or defendant may be joined as parties to a claim." The Court construed these rules as meaning what they stated.

Noting proposed tests for whether claims could proceed in one set of proceedings as suggested in Abbott, the Court of Appeal held "that 19.1 and 7.3 must be construed as meaning what they say: any number of claimants or defendants may be joined as parties to proceedings, and claimants may use a single Claim Form to start all claims which can be conveniently disposed of in the same proceedings. There is no exclusionary rule of real progress, real significance or otherwise. The court will determine what is convenient according to the facts of every case" [our emphasis].

In this instance, the Court of Appeal found that the claims forming the background to the appeal could be conveniently disposed of in the same proceedings. The judgment called upon the Civil Procedure Rules Committee to consider whether the rules as currently drafted were working well.

The question of convenience

Following the decision in Morris, the question of 'convenience' was addressed in the claim of Adams v Ministry of Defence⁴. The action was not a data breach claim. A number of ex-military personnel had pursued injury claims against the Ministry of Defence. Claims for noise-induced hearing loss and non-freezing cold injuries had been pursued via the omnibus Claim Form route. A number of lead claims had been resolved, at which time it was apparent that the "resolution of generic issues by agreement had fulfilled the primary purpose or motive for the joinder of multiple claimants. From that point on, the claims were being, and could only be, progressed and tried individually."

Further, the progression of the claims had been complicated by the use of the Court's CE-file digital document management system, which prevented effective management of the outstanding claims issued via omnibus Claim Form. The omnibus Claim Form was therefore, now effectively, a repository for claims, which when made active, were transferred to a new separate court file with a new case number.

The High Court considered whether the claims in question could continue via omnibus Claim Form, or an alternative procedural vehicle.

The issue of 'convenience' was considered to be the acid test, and one which was a matter of broad judicial discretion. Adding to the judicial comments on the suitability of omnibus Claim Forms, the High Court stated that "convenience is not to be judged exclusively from the perspective of the parties. It seems to us legitimate and appropriate also to take into account the convenience and capacities of the court and the court system."

Although the disaggregation of claims originally properly joined by one Claim Form was within its case management powers, the Court decided that the claims should continue to proceed through the use of a single Claim Form. Requiring new individual Claim Forms would be "essentially duplicative… which would impose its own administrative burden on the court." There was a desire not to cause further upheaval on the parties, indicating the case management history was a relevant factor.

However, the postscript to the decision was of most interest to those considering the use of an omnibus Claim Form:

"Where it appears at the outset that claims which are sought to be joined to an omnibus Claim Form will not, via trial of lead cases, be dispositive or at least largely dispositive of the cohort, that is a relevant factor in deciding whether to issue an omnibus Claim Form. To put that differently, if it can be anticipated that a stage will be reached where the cases in the cohort will all require individual determination, then a court may be hesitant to approve the use of an omnibus Claim Form because of the practical difficulties that may be encountered and as are exemplified by this case. To put that differently again, the convenience of such a Claim Form may be short-lived."

What does motor finance have to do with it?

The recent decision of Stuart Angel v Black Horse Limited⁵, an action relating to claims against motor finance companies for undisclosed discretionary commissions paid to brokers or car dealers. The claims, which totalled in excess of 5,000 claimants, had been grouped into eight omnibus Claim Forms. Each Claim Form was directed at a different lender.

The Defendants had previous challenged the appropriateness of the use of the omnibus Claim Form route, arguing that the claims were fact-specific, and could not be conveniently disposed in the same proceedings. HHJ Worster, during case management, agreed with the Defendants, severing/disaggregating the claims meaning that each Claimant was required to issue a separate and individual Claim Form. HHJ Worster referred to the guidance providing in Abbott in his decision.

The Claimants successfully appealed.

In the High Court, Mr Justice Ritchie referred to the decision in Morris, noting it provided the current governing guidance for the application of CPR 7.3 and 19.1 in omnibus claims, and in the exercise of his discretion, set out a number of factors relevant to his decision:

• The claims related to a single defendant in each instance.
• The number of claimants totalled in excess of 5,800 individuals. The appeal had submitted that the costs of bringing these claims individually would be disproportionate, and the administrative burden of issuing within the deadline would likely result in a number of claims being struck out.
• The common, broad allegations pleaded were similar or the same.
• The same cause of action was pleaded across the claims.
• There are broad common issues across the claims and within those are likely to be many specific common issues across all the claims and some common issues specific to bundles of claims.
• The case-specific claims raised common issues relating to fact and matters and law.
• The omnibus process would assist in the selection of lead cases, avoiding random early trials. The significance of lead case decision would be persuasive and result in a greater likelihood of solving the main issues early.
• The overriding objective would be better met through the omnibus route as access to justice would be better served for those claimants with small claims or fast track actions. Expert evidence may be necessary, would not necessarily permissible in small claims and would be disproportionately expensive across small claims or fast track claims.

What do these decisions mean for data breach claims?

The importance of balancing procedural efficiency with access to justice when dealing with claims involving common legal and factual issues is made clear in the above judgments.

The judgments highlight the potential flexibility of the omnibus Claim Form approach in handling multi-party litigation, and why this approach may be attractive to claimants and their representatives when pursuing data breach actions. The nature of many data breach actions, in that they relate to a breach involving a single defendant breaching the same data protection rights of many individuals.

Claimant data breach practitioners may also find comfort in the judicial comments that the omnibus route assists access to justice for those claimants with small claims and fast track claims. Similarly, although it was noted that defendants may be disadvantaged when compared to the absence of claimants legal costs on the small claims track, costs overall may be saved through the early settlement of other cases once lead cases are resolved.

That being said, there are still material uncertainties in relation to the use of omnibus Claim Forms in data breach claims, particularly where the impacted data and effect on individuals is not uniform or easily measured. Existing data breach compensation judgments typically focus on the individual circumstances of the claimant which may create a hurdle when it comes to meeting the "same or similar" threshold for omnibus Claim Forms.

This article has been co-authored by Hans Allnutt & Emilia Varbanova.

[1] [2025] EWHC 490 (KB), paragraph 24

[2] [2024] EWCA Civ 376

[3] [2023] EWHC 2389 (KB)

[4] [2024] EWHC 1966 (KB)

[5] [2025] EWHC 490 (KB)