News & Analysis

Glyphosate Lawsuits, EPA Labeling, and the Supreme Court

By David Meldofsky

Published April 28, 2026 · Updated May 10, 2026

Durnell v. Monsanto puts FIFRA preemption back before the Supreme Court two decades after Bates v. Dow Agrosciences. The narrow question is about Roundup labeling. The broader question is whether federal agency approval of a product's warnings can shut down state-law failure-to-warn claims across federally regulated consumer products generally — pesticides today, but potentially much more.

The case got to the Supreme Court because the circuits disagree. The Ninth Circuit in Hardeman v. Monsanto allowed Roundup failure-to-warn claims to proceed, reading Bates to mean state-law claims aren't preempted unless they impose labeling requirements stricter than federal law. The Third Circuit in Schaffner v. Monsanto went the other way, holding that EPA's repeated determinations that glyphosate doesn't require a cancer warning effectively preempt state-law claims that would require one. Both circuits applied the same statute and the same Supreme Court precedent. Both came out differently. That's the split Durnell is meant to resolve.

Why glyphosate is back in the news

Glyphosate is the active ingredient historically associated with Roundup weedkiller. Roundup lawsuits have alleged for years that exposure to glyphosate-based products contributed to cancer, particularly non-Hodgkin lymphoma. Bayer, which acquired Monsanto in 2018, has paid billions in settlements while continuing to dispute the underlying causation science and pursuing the preemption defense in case after case.

The current attention isn't about new science. It's about the Supreme Court agreeing to decide whether the preemption defense works. If it does, a substantial chunk of pending and future Roundup litigation collapses. If it doesn't, Bayer's path to ending the litigation through doctrine narrows considerably and the company faces years more of individual cases.

The doctrinal question: Bates and what it actually held

The Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) governs pesticide registration and labeling. Section 24(b) of FIFRA preempts state requirements for labeling "in addition to or different from" federal requirements. The fight is over what that phrase means when applied to common-law tort claims that, if successful, would functionally require a manufacturer to add a warning the federal label doesn't have.

Bates v. Dow Agrosciences (2005) is the controlling precedent and it's narrower than Bayer's preemption argument suggests. Bates held that FIFRA does not preempt state-law tort claims that are merely "parallel" to federal labeling requirements — in other words, claims premised on the same misbranding standard FIFRA itself imposes. Bates was not a sweeping endorsement of preemption. It was a Supreme Court rejection of the broad preemption reading the agrochemical industry had been advancing.

The Third Circuit's Schaffner decision largely sidestepped this by reasoning that EPA's repeated, specific determinations on glyphosate cancer labeling create a kind of regulatory finality that Bates didn't directly address. The Ninth Circuit's Hardeman decision, by contrast, treated Bates as straightforward: state-law failure-to-warn claims survive unless they impose requirements beyond what federal law requires, and a state jury concluding that a manufacturer should have warned about cancer risk doesn't necessarily impose a different requirement than FIFRA itself.

My read: the Ninth Circuit is closer to Bates

The Third Circuit's framing is intellectually appealing but doctrinally aggressive. It effectively reads Bates as having drawn a line that Bates didn't draw, and it gives EPA labeling determinations a preemptive force the statute itself doesn't clearly grant. Bates, fairly read, expects state tort claims to coexist with FIFRA labeling unless the state-law requirement is genuinely additional or different. That's not a hard standard to meet for plaintiffs whose claims rest on a misbranding theory rooted in the same scientific record EPA itself reviewed.

That said, the Court's preemption doctrine has shifted modestly in industry's favor since Bates, and a textualist majority could find ways to expand Schaffner's reasoning without overruling Bates outright. The most likely scenario, in my view, is a narrow ruling that reaffirms Bates's general framework while drawing a more specific line about when EPA's labeling determinations have preemptive weight — a ruling that doesn't kill Roundup litigation but reshapes how plaintiffs frame their claims to survive.

Why this case is bigger than Roundup

FIFRA preemption is a narrow statutory question on its face. But the doctrinal logic of Durnell applies to every federally regulated consumer product where the manufacturer can point to an agency labeling determination as a shield against state-law warning claims. That includes pharmaceuticals (where the analogous fight is ongoing under Wyeth v. Levine), medical devices, food additives, cosmetics, and a long list of other categories where federal agencies make labeling decisions that industry would prefer to use as preemption defenses.

A broad pro-preemption ruling in Durnell would ripple. Plaintiff-side bar groups know this and are watching the case for that reason as much as for the Roundup outcome. So is industry.

The political overlay matters but doesn't drive the case

Reporting has described tension within the Make America Healthy Again coalition over the administration's litigation posture on glyphosate. That tension is genuine and reflects a real cross-pressure on Republican policy: the agribusiness industry has historically pushed for strong preemption protections, while a vocal segment of the populist health-policy right is skeptical of the regulatory determinations those protections rely on.

None of that decides the legal question. The Court will rule on FIFRA's preemption text, not on coalition politics. But the political overlay helps explain why a relatively technical preemption case is getting broader public attention than most statutory-construction disputes.

What courts will likely struggle with

A few things worth watching beyond the headline framing:

The "parallel claim" line is harder to draw than it sounds. Bates said state-law claims survive when they're "parallel" to federal requirements. Lower courts have struggled for twenty years to define what counts as parallel versus additional. Durnell may force the Court to clean up this distinction, and how it does so will matter more than the bottom-line ruling.

EPA's regulatory record is uneven. EPA has reaffirmed glyphosate's safety multiple times, but the agency's process has also been criticized in court — the Ninth Circuit vacated EPA's 2020 glyphosate registration decision in NRDC v. EPA, finding the agency's analysis inadequate. A Court inclined toward preemption will have to decide how much deference to give a regulatory record that itself has been judicially questioned.

Settlement leverage shifts before any opinion comes down. Bayer has been settling Roundup cases for years using a portfolio approach. The pendency of Durnell changes plaintiffs' settlement calculus right now — some plaintiffs and firms will want to lock in settlements before a potential adverse ruling, others will hold for the upside. That dynamic affects valuations of pending cases regardless of how Durnell ultimately comes out.

Watch the briefing for what isn't there. If the Solicitor General files a brief that doesn't fully back Bayer's preemption argument, that would be a meaningful tell. The administration's position carries weight with the Court even where it doesn't bind.

Bottom line

Durnell is a Roundup case in name and a preemption case in substance. The most likely outcome is a narrow ruling that preserves Bates's framework while drawing tighter lines around when agency labeling carries preemptive weight — a result that doesn't end Roundup litigation but changes how plaintiffs plead it. The broader implication for federally regulated consumer products is the part of this case worth watching, even for readers who don't care about pesticides.

Sources and further reading

• NPR: MAHA, EPA, pesticides, and glyphosate
• Reuters: Roundup maker goes to Supreme Court as Americans worry about pesticides
• SCOTUSblog: Federal and state rules for cancer warnings on pesticides
• Bayer: Statement on Durnell Supreme Court filing

Educational commentary only. Not legal advice. No attorney-client relationship is created.