WASHINGTON — The U.S. Supreme Court agreed Friday to hear Bayer’s appeal aimed at limiting lawsuits that claim its Roundup weedkiller caused cancer. The Roundup Supreme Court dispute turns on whether federal pesticide-label rules override state “failure to warn” claims when regulators have not required a cancer warning, Jan. 20, 2026.
The Roundup Supreme Court case stems from a Missouri verdict for John L. Durnell, who was awarded $1.25 million after a St. Louis jury found he developed non-Hodgkin lymphoma after years of exposure to Roundup. Bayer, through its Monsanto unit, argues that because it complied with federal labeling decisions, state courts should not be able to hold it liable for not adding a cancer warning.
What the Roundup Supreme Court case will decide
As laid out in the Supreme Court docket for Monsanto Co. v. Durnell, the justices granted review on a narrow question: whether the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) preempts a label-based failure-to-warn claim where the Environmental Protection Agency has not required the warning.
Bayer says it cannot simply add language to Roundup’s label, because pesticide labels are regulated through the EPA’s registration and approval process. The company points to the agency’s longstanding position that glyphosate — Roundup’s key ingredient — is “unlikely to be a human carcinogen” when used as directed, according to EPA’s glyphosate overview.
Durnell’s side argues the case is not just about what appears on a label. Plaintiff lawyers have said many consumers relied on marketing and other representations about Roundup’s safety — and that state-law claims remain an essential way to test allegations that people were not adequately warned.
Why the Roundup Supreme Court fight matters
The Roundup Supreme Court review is being watched well beyond the pesticide industry, because it could clarify how far federal regulators’ decisions can shield manufacturers from state tort suits. Bayer has said it faces about 65,000 similar cases still active, after years of trials, appeals and settlements.
Bayer CEO Bill Anderson said companies “should not be punished under state laws for complying with federal warning label requirements.” Opponents say the court’s decision to hear the appeal risks shutting the courthouse doors to people who say Roundup exposure contributed to their cancers. Lori Ann Burd, environmental health director at the Center for Biological Diversity, called it “a sad day in America” for Roundup users seeking accountability.
The case also lands in the middle of a long-running legal saga. After Bayer acquired Monsanto, it disclosed thousands of glyphosate lawsuits in 2018, reported in a Reuters story on the early wave of claims. In 2020, Bayer agreed to pay up to $10.9 billion to settle much of the Roundup docket, outlined in a 2020 Reuters report on the broad settlement. And in 2022, the Supreme Court declined to hear a similar preemption appeal, described in an AP report on the court’s earlier refusal.
Since then, lower courts have split further. In 2024, the 3rd U.S. Circuit Court of Appeals sided with Monsanto on preemption in Schaffner v. Monsanto, a decision Bayer has cited as part of the conflict the Roundup Supreme Court case is now positioned to address, in the 3rd Circuit’s opinion.
Oral arguments have not yet been scheduled. Bayer said it expects a decision by the end of the court’s term in June, in Bayer’s statement welcoming the review in the Durnell case. Whatever the outcome, the Roundup Supreme Court ruling is likely to shape how future failure-to-warn lawsuits are litigated — or curtailed — across the country.
