Understanding How GLP-1 Lawsuits Are Handled in U.S. Courts
If you’ve been following GLP-1 drug litigation — or if you’re considering whether you have a viable claim involving Ozempic, Wegovy, Mounjaro, or Zepbound — you’ve almost certainly encountered two terms that tend to generate confusion: multidistrict litigation, universally abbreviated as MDL, and class action. News coverage often uses these terms interchangeably, and some attorneys are not always careful about the distinction. But these are fundamentally different legal structures, and understanding how they work — and which one applies to GLP-1 cases — is essential for anyone navigating this litigation.
The short version: GLP-1 lawsuits are being handled as MDLs, not class actions. The distinction matters enormously for how your case is managed, how compensation is determined, and what rights you retain as a plaintiff. There is also a New Jersey state court litigation that is being handled as a multi-county litigation and not a class action.
May lay people regularly discuss what they call an “ozempic class action.” First of all, the glp-1 cases are not class actions in the United States. Secondly, there is no such thing as an ozempic class action.
What Is an MDL (Multidistrict Litigation)?
Multidistrict litigation is a procedural mechanism built into federal law that allows cases filed in different federal districts across the country to be transferred to a single federal court for coordinated pretrial proceedings. The governing statute — 28 U.S.C. § 1407 — authorizes the Judicial Panel on Multidistrict Litigation (JPML), a body of seven federal judges, to order these transfers when cases involve common questions of fact and when consolidation would serve the convenience of the parties and promote efficient judicial administration.
The key conceptual point is that an MDL does not merge individual lawsuits into a single case. Each plaintiff retains their own lawsuit, their own attorney, and their own path to resolution. What changes is the pretrial process. Rather than having hundreds or thousands of federal judges across the country independently managing identical discovery disputes, hearing duplicative expert testimony, and issuing potentially inconsistent rulings on the same legal questions, those pretrial functions are handled once, by one judge, in one court. In the GLP-1 MDL, that court is the Eastern District of Pennsylvania, and the presiding judge is the Honorable Karen S. Marston. The MDL functions as follows:
- Similar lawsuits from across the country are grouped together and assigned to a single federal judge
- Pretrial proceedings — including discovery, expert challenges, and dispositive motions — are coordinated across all cases
- Evidence and discovery developed in the MDL are shared among all participating plaintiffs
- Each case nonetheless remains separate and individual throughout the process
Key Features of an MDL
Understanding the structural features of MDL proceedings helps clarify why they are so commonly used in mass pharmaceutical tort litigation and what plaintiffs can realistically expect. The defining characteristics of an MDL include:
- Each plaintiff files and maintains an individual lawsuit with their own specific allegations
- Cases are consolidated for pretrial purposes only — not for trial. However, each case will have a number of bellwether trials to help the parties resolve the claims.
- Shared discovery means expert witnesses, depositions, and documentary evidence are developed once and available to all plaintiffs
- Cases may ultimately be remanded (returned) to their original district courts for individual trials if they do not resolve through settlement
Why MDLs Are Used in Mass Tort Litigation
MDLs were specifically designed for situations where a single product, event, or course of conduct has produced a large volume of similar but not identical lawsuits. They are not appropriate for every multi-plaintiff dispute, but they are the standard procedural vehicle for pharmaceutical mass torts, and for good reason. MDLs are deployed when:
- Thousands of people across different states have been injured by the same product
- The underlying factual and legal questions — such as what the manufacturer knew and when — are substantially the same across cases
- Judicial efficiency and consistency in pretrial rulings are important priorities
The GLP-1 MDL encompasses claims related to gastroparesis, bowel obstruction, and other gastrointestinal injuries. A separate MDL has been established specifically for NAION vision loss claims. Both are pending before Judge Marston in the Eastern District of Pennsylvania.
What Is a Class Action Lawsuit?
A class action is a fundamentally different legal structure. Rather than grouping individual lawsuits together while keeping them separate, a class action merges all claims into a single lawsuit. One or a small number of named plaintiffs — called class representatives — litigate on behalf of an entire defined group, known as the class. The class representative’s case is tried, and the outcome — whether a judgment or a settlement — applies to every member of the class, typically without those members having any meaningful individual participation in the litigation.
For a case to proceed as a class action under Rule 23 of the Federal Rules of Civil Procedure, plaintiffs must satisfy a number of requirements. The class must be sufficiently numerous, the legal questions must be common across class members, the named plaintiffs must be typical of the class, and the named plaintiffs and their counsel must adequately represent the class’s interests. Class actions tend to work well for a particular type of dispute:
- Consumer fraud cases where many people suffered identical or nearly identical harm
- Defective products that caused standardized, relatively modest damages across a large population
- Securities fraud cases where a standard class-wide remedy makes sense
- Situations where individual lawsuits would be economically impractical given the size of each person’s claim
Key Features of a Class Action
The structural characteristics of a class action stand in direct contrast to those of an MDL. The core features include:
- One lawsuit represents the entire class of plaintiffs
- Named class representatives control the litigation on behalf of all class members
- Individual plaintiffs generally do not participate in the litigation and have no independent attorney-client relationship with class counsel
- Settlements apply to all class members and are typically divided according to a standardized formula
- Individual circumstances, medical histories, and injury severity are generally not evaluated on a plaintiff-by-plaintiff basis
The Key Differences Between MDL and Class Action
The distinctions between these two procedural structures are not merely technical — they have real and significant consequences for plaintiffs in terms of compensation, control, and the trajectory of their cases. The following comparison captures the most important differences.
| MDL (Multidistrict Litigation) | Class Action |
| Each plaintiff maintains an individual lawsuit | One lawsuit represents all plaintiffs |
| Injuries are evaluated individually | Injuries are treated collectively |
| Compensation reflects personal severity, medical costs, and long-term impact | Compensation is standardized and divided among class members |
| Plaintiff retains control over their own claim | Decisions are made for the entire class; individual control is limited |
| Cases may go to individual trial; bellwether trials help guide settlement | Resolved as a group; individual trials are rare |
| Resolution can take several years | Faster resolution is possible but payouts are typically smaller |
What Are Bellwether Trials in an MDL?
Bellwether trials are one of the most strategically important features of MDL proceedings, and they are worth understanding in some depth. After the pretrial phase of an MDL is complete — once discovery has been conducted, experts have been designated, and dispositive motions have been resolved — the presiding judge typically selects a small number of representative cases to proceed to trial. These are the bellwether cases.
The term comes from the practice of hanging a bell on the lead sheep in a flock, whose movement signals where the others will follow. In litigation, bellwether trials serve an analogous function: they test the strength of the legal theories and evidence, expose weaknesses on both sides, and — perhaps most importantly — give both plaintiffs and defendants a concrete data point on what juries are likely to do. The specific purposes bellwether trials serve in an MDL include:
- Testing the persuasiveness of key legal arguments and the admissibility of expert testimony
- Evaluating how juries respond to the evidence and the parties’ respective narratives
- Generating settlement value benchmarks that inform global resolution negotiations
In the GLP-1 MDL, bellwether trials are anticipated in 2026 and beyond. The outcomes of those trials are expected to be the single most significant driver of any eventual global settlement, as they will give both sides a much clearer picture of litigation risk.
Why GLP-1 Lawsuits Are Not Class Actions
Some plaintiffs — and some members of the public following this litigation — have asked whether GLP-1 cases could or should be structured as a class action. The answer is almost certainly no, and the reason comes down to the fundamental incompatibility between the class action requirements and the nature of GLP-1 injuries.
Class actions work when the harm suffered by class members is substantially uniform — when one resolution genuinely fits all. GLP-1 injuries are the opposite of uniform. The range of claimed injuries spans gastroparesis of varying severity, bowel obstruction requiring emergency surgery, permanent vision loss from NAION, and other serious complications. The drugs involved include multiple different products with different mechanisms and labeling histories. Patients’ medical backgrounds, comorbidities, dosing histories, and the duration of their treatment vary enormously. Consider the contrast between two hypothetical plaintiffs:
- One plaintiff experienced transient nausea and mild gastric symptoms that resolved within weeks of stopping treatment
- Another spent weeks hospitalized following emergency surgery for bowel obstruction, required a period of rehabilitation, and sustained permanent functional limitations
A class action settlement structure — which would divide a fixed fund among all class members using standardized criteria — would almost certainly undercompensate severely injured plaintiffs while providing marginal recoveries to those with minor injuries. An MDL, by contrast, allows each plaintiff’s compensation to be calibrated to the specific facts of their case.
Advantages of MDLs for GLP-1 Plaintiffs
For individuals with legitimate GLP-1 injury claims, the MDL structure offers several meaningful advantages over both individual litigation and the class action model.
A. Individualized Compensation
Because each plaintiff maintains their own case within the MDL, compensation can be tailored to the specific nature and severity of their injuries. Relevant factors in assessing individual claim value include:
- The severity and duration of the injury
- Medical costs incurred, both past and anticipated future expenses
- Lost wages and diminished earning capacity
- Long-term functional impact and quality of life effects
B. Shared Resources Reduce Cost and Complexity
One of the most significant practical benefits of MDL consolidation is the sharing of litigation resources across the plaintiff pool. Developing expert testimony on complex medical and scientific questions — such as the causal relationship between semaglutide and NAION, or the adequacy of Novo Nordisk’s warnings — is extraordinarily expensive. In an MDL, those costs are borne collectively rather than duplicated in every individual case. Shared resources include:
- Expert witnesses on medical causation, pharmacology, and regulatory standards
- Document discovery and the review of millions of pages of manufacturer records
- Legal research and motion practice on common legal questions
C. Judicial Efficiency
Centralizing pretrial proceedings before a single judge produces faster and more consistent outcomes than having the same disputes litigated independently in courts across the country. Judge Marston and her team develop deep familiarity with the scientific evidence, the parties’ arguments, and the factual record — expertise that benefits all parties in the litigation.
D. Increased Negotiating Leverage
The sheer scale of the GLP-1 MDL — which already encompasses thousands of cases and is expected to grow significantly — creates substantial pressure on Novo Nordisk and Eli Lilly to reach a global resolution. No pharmaceutical company wants to face thousands of individual trials. That dynamic, combined with the evidence developed through coordinated discovery, gives plaintiffs considerably more negotiating leverage than they would have filing individually.
Disadvantages and Realistic Expectations for MDL Plaintiffs
MDLs are not without their limitations, and plaintiffs and their attorneys should approach this litigation with clear-eyed expectations about what the process realistically involves.
A. Extended Timelines
Large pharmaceutical MDLs are not resolved quickly. The coordination of discovery across thousands of cases, the development and vetting of expert testimony, bellwether trials, and global settlement negotiations all take time. Plaintiffs entering the GLP-1 MDL should be prepared for a process that may extend over several years before any individual resolution is reached.
B. No Guaranteed Outcome
Participation in an MDL does not guarantee a settlement or any particular recovery. Some cases will settle globally; others may be remanded for individual trial; some may not survive dispositive motions. The strength of an individual plaintiff’s case — including the nature of their injury, the quality of their medical documentation, and the evidentiary basis for causation — will significantly influence their outcome.
C. Procedural Complexity
MDL proceedings involve layers of procedural structure — case management orders, leadership committees, master complaints, short-form complaint processes — that can be difficult to navigate without experienced counsel. Plaintiffs should ensure they are represented by attorneys with demonstrated experience in pharmaceutical mass tort litigation specifically.
How Settlements Work in GLP-1 MDL Cases
The vast majority of large pharmaceutical MDLs ultimately resolve through negotiated global settlements rather than individual trials. The GLP-1 litigation is expected to follow this pattern, though the timing and structure of any eventual settlement will depend heavily on the outcomes of bellwether trials and the parties’ assessment of overall litigation risk.
In a typical MDL global settlement, a defendant agrees to pay a total sum into a settlement fund, and that fund is distributed among participating plaintiffs according to a point-based or tiered compensation matrix. The factors that typically drive individual allocation within a settlement matrix include:
- The severity of the injury and its impact on daily function
- The duration of GLP-1 use prior to the onset of symptoms
- The medical treatment required, including hospitalizations and surgeries
- The long-term prognosis and any permanent effects
- The strength of the causal connection between GLP-1 use and the claimed injury
Why This Distinction Matters for Your Claim
Understanding the difference between an MDL and a class action is not just an academic exercise — it has direct practical implications for anyone considering whether to pursue a GLP-1 injury claim. The MDL structure means that you are not simply “joining” a class action where your outcome is determined by what happens to everyone else. You are filing your own individual lawsuit, with your own attorney, based on your own specific medical history and injuries.
This structure also means that the quality of your documentation — your medical records, your prescription history, your treating physicians’ findings — matters. In a class action, individual circumstances are largely averaged away. In an MDL, they are the foundation of your case. Several important points follow from this:
- GLP-1 lawsuits are not and will not be structured as class actions, given the variability of injuries involved
- Each plaintiff’s compensation potential is tied to the specific facts and severity of their individual case
- Bellwether trial outcomes in 2026 are expected to be the primary driver of eventual global settlement terms
- Plaintiffs with well-documented, severe injuries are generally best positioned within the MDL framework
Frequently Asked Questions
Are GLP-1 lawsuits a class action?
No. GLP-1 injury lawsuits are proceeding as multidistrict litigation — specifically MDL No. 3094 in the Eastern District of Pennsylvania, as well as a separate MDL for NAION vision loss claims, both before Judge Karen S. Marston. In an MDL, each plaintiff maintains their own individual lawsuit rather than being absorbed into a single collective case.
If I join the MDL, do I give up control of my case?
No. Joining the MDL does not mean surrendering control of your individual claim. You retain the right to accept or reject any settlement offer, and your case is evaluated on its own merits. The MDL structure coordinates the pretrial process — it does not merge your case into a single uniform outcome.
How long will the GLP-1 MDL take to resolve?
Large pharmaceutical MDLs typically take several years from centralization to global resolution. The GLP-1 MDL was established in early 2024. Bellwether trials are anticipated in 2026. A global settlement, if reached, would likely follow the bellwether outcomes, potentially in 2027 or later depending on how the litigation develops.