Large-scale litigation is not simply an ordinary lawsuit scaled up. When thousands of similar claims move through the courts at the same time, they become a distinct kind of enterprise – one with its own economics, its own management structures, and its own professional roles. Understanding how that enterprise works means looking at three things: how claims are grouped, how the work is financed, and how money is distributed once a case ends.
What actually counts as large-scale litigation
Two procedural devices do most of the heavy lifting. The first is the class action, in which one or a few representative plaintiffs sue on behalf of a larger group whose claims share common questions of law or fact. As the Cornell Legal Information Institute explains, the outcome binds all class members – including people who never appear in court – which is why courts apply careful procedural safeguards before allowing a case to proceed as a class.
The second is the mass tort, defined as a civil action involving numerous plaintiffs against one or a few defendants whose conduct caused similar injuries. A defective product, a prescription drug, a medical device, or a contamination event can each generate thousands of individual claims. In United States federal courts, mass tort claims are frequently consolidated as multidistrict litigation (MDL) rather than certified as a single class.
The economics of representing a case
Large-scale litigation is often financed on a contingent-fee basis. A contingency fee is defined as a fee payable only if the representation produces a favourable result, typically calculated as a percentage of the amount recovered. The general overview of contingent fees notes that the permitted percentage varies by country and even by local jurisdiction, that professional-conduct rules generally require fees to be reasonable, and that some jurisdictions impose statutory caps in specific categories such as medical malpractice.
The practical effect is a transfer of risk. Instead of paying an hourly rate while a case runs, the client exposes the lawyer to the possibility of receiving nothing. That structure also shapes which cases get accepted: firms generally assess both the merits and the defendant’s ability to pay before committing resources, because a favourable judgment against a party with no funds to satisfy it may still produce no recovery.
Contingency arrangements are one option among several. Hourly billing, fixed fees, conditional fee agreements with a success uplift (common in England and Wales), and damages-based agreements all appear in commercial disputes. Which one is used often depends on the client’s resources, the size of the claim, and the jurisdiction.
Why aggregation changes the business
Aggregating claims transforms the unit economics. In a federal class action, Rule 23 of the Federal Rules of Civil Procedure requires a court to find that the class is so numerous that joinder is impracticable, that common questions predominate, that the representative’s claims are typical of the class, and that the representatives will adequately protect the interests of everyone involved. Only then can the case proceed as a class.
For the most common type of consumer and employment class – the Rule 23(b)(3) damages class – every member who can reasonably be notified must receive notice, and each has the right to opt out and pursue an individual claim. This notice and opt-out machinery is a substantial operational cost in its own right, and it is usually administered by specialised settlement administrators rather than by the lawyers themselves.
The Class Action Fairness Act of 2005 made it easier to move certain large class actions into federal court, which added a further layer of forum strategy to the business. In parallel, arbitration clauses and class-action waivers in consumer and employment contracts have narrowed the routes by which some claims can be aggregated at all.
Mass torts and the MDL machine
Multidistrict litigation works differently from a class action. Under 28 U.S.C. § 1407, the Judicial Panel on Multidistrict Litigation can centralise civil actions pending in different federal districts when they share common questions of fact. The cases are transferred to a single judge for coordinated pretrial proceedings and discovery. If a case is not settled or dismissed, it is normally sent back to its original court for trial. New filings that share the same facts – known as tag-along actions – are usually added to the same proceeding.
The scale is significant. Data published by the Judicial Panel on Multidistrict Litigation and reported by the ABA’s Litigation News showed that at the close of 2018, 51.9 percent of all pending federal civil cases had been centralised into MDLs – the first time more than half of the federal civil docket sat inside these proceedings. Of 301,766 pending civil cases, 156,511 were pending across 248 MDLs. Measured by number of MDLs, products liability accounted for 32.9 percent, antitrust 24.1 percent, and sales practices 12.1 percent; within the total volume of cases inside MDLs, products liability was dominant at roughly 91 percent.
Because MDLs operate largely outside the ordinary rulebook taught in law schools, they have attracted debate from both plaintiff and defence lawyers about case management, transparency, and the protection of individual claimants. Those debates are about process design; the mechanism itself is established federal procedure.
Who funds a large case before it pays out
Not every claim is funded by the lawyers who bring it. Third-party litigation funding allows an outside investor to finance legal costs in exchange for a share of any eventual recovery. As the overview of legal financing describes, such advances are generally non-recourse: if the case loses, the funder receives nothing and the claimant does not repay the advance. Funders therefore assess legal merit, the size of potential damages, and whether the defendant can actually pay a judgment.
The market splits broadly into consumer funding, often small advances to individual plaintiffs, and commercial funding aimed at paying litigation costs for companies. The regulatory picture varies widely. In England and Wales, a 2023 Supreme Court decision (the PACCAR case) held that certain litigation funding agreements were unenforceable as drafted, prompting calls to revisit the rules. The European Parliament has called for regulation of third-party funding, and in the United States, proposals for mandatory disclosure of funding arrangements have been debated before the courts and in Congress. These are live policy questions rather than settled law.
How money moves after a settlement
Most large-scale cases end in settlement rather than trial, and settlements follow a recognisable sequence. The parties agree on a total figure, which is typically paid into a settlement fund. In class actions, a court must review and approve both the settlement and the fees and costs requested by class counsel, because the fund belongs to the class as a whole – not to the lawyers or the defendant.
Once approved, a claims administrator notifies class members, sets a deadline for claims, and evaluates submissions. Distributions are then calculated according to the terms of the settlement agreement: some settlements pay a fixed amount per eligible person, some reflect documented losses, and some use a formula. The details depend entirely on the specific agreement and the court’s order, so no general rule describes every case.
Where an individual claim is resolved rather than a class claim, the claimant’s own contingent-fee agreement governs the split, and other obligations – such as statutory liens, medical liens, or costs advanced during the case – may be settled from the recovery before the client receives the remainder. These deductions are contractual and jurisdictional, not universal.
How the three main structures compare
| Feature | Class action | Mass tort / MDL | Individual lawsuit |
|---|---|---|---|
| How claims are grouped | One representative suit binds the class, with opt-out rights where applicable | Many individual suits coordinated for pretrial proceedings | A single plaintiff against a single defendant |
| Who manages the case | Court-appointed class counsel and a representative plaintiff | A transferee judge, often with lead or liaison counsel | The claimant’s own lawyer |
| Common fee structure | Contingency fee paid from a common fund, subject to court approval | Individual contingency agreements, often with assessments for shared costs | Contingency, hourly, or fixed fee |
Structure summaries are based on the Cornell Legal Information Institute’s overview of class actions, the federal multidistrict litigation statute (28 U.S.C. § 1407), and the Wikipedia overview of legal financing, all reviewed in 2026. Fee arrangements vary by jurisdiction and by contract.
The roles behind the scenes
A large case is an operation as much as a legal argument. It usually involves lead and liaison counsel coordinating dozens of firms, document-review teams processing millions of pages during discovery, economists and damages experts, settlement administrators, and insurers standing behind defendants. Discovery alone can be one of the largest cost centres, which is one reason aggregation exists: repeating the same evidence and expert work in thousands of separate trials would be impractical for courts and litigants alike.
Large-scale litigation is also a professional sector in its own right, with firms building dedicated practices, recruitment pipelines, and case-management technology around it. As those markets evolve, industry publications provide further legal coverage of how firms organise and compete for this work, while courts and regulators continue to refine the rules that govern it.
Frequently asked questions
What is the difference between a class action and a mass tort?
A class action resolves the claims of a defined group in a single representative lawsuit, and the judgment or settlement generally binds all members. A mass tort involves many individual claims that are usually coordinated – often as multidistrict litigation – but each claimant generally retains an individual case that can be resolved or tried separately.
How do lawyers get paid in large-scale litigation?
Contingency fees are common, meaning the fee is payable only on a favourable result and is usually a percentage of the recovery. Hourly billing, fixed fees, and conditional fee arrangements also exist. In class actions, the court reviews and must approve the fees paid to class counsel.
Who decides how much class counsel is paid?
The court does. Because the money comes from a fund that belongs to the class, the judge evaluates the requested fee against legal standards and the terms of the settlement. The percentage that is reasonable depends on the jurisdiction and the facts of the case.
What happens to the money in a settlement fund?
An approved administrator notifies eligible claimants, collects claims by a deadline, and distributes payments under the terms of the settlement agreement. Fees, administrative costs, and approved expenses are typically deducted before or alongside distribution, as set out in the court’s order.
Can someone be included in a class action without knowing about it?
For the damages classes covered by Rule 23(b)(3), class members who can reasonably be located must receive notice and may opt out. Other types of classes may not carry the same notice and opt-out rights, which is why the applicable rule and the court’s certification decision matter.
What is multidistrict litigation used for?
It is used to coordinate federal cases that share common questions of fact, such as product-liability or antitrust disputes, before a single judge for pretrial proceedings and discovery. If a case does not resolve, it is normally returned to its original court for trial.
Why the structure matters more than any single case
Large-scale litigation looks dramatic from the outside, but the business underneath it is largely a matter of risk allocation and process design. Who bears the cost of a case while it is pending, how claims are grouped so that courts can handle them, who reviews the terms of a settlement, and how a fund is distributed are all decided by rules, contracts, and court orders – not by any one participant’s preference.
For anyone trying to understand a headline about a big settlement or a sweeping lawsuit, the useful questions are procedural: was this certified as a class or coordinated as an MDL, is the case funded internally or by a third party, and whose approval must the final terms receive? Those answers explain far more about an outcome than the headline figure alone.
