High court sides with Monsanto on Roundup cancer warning label

The U.S. Supreme Court, on a 7-2 vote, sided with Monsanto, ruling states cannot exceed the federal government’s labeling requirements for Roundup in agricultural practices.

The case is known as Monsanto v. Durnell. John Durnell sued Monsanto in Missouri state court in 2019, alleging he had used Monsanto’s Roundup products for about 20 years and that they caused his non-Hodgkin lymphoma. Durnell sued under a failure-to-warn theory.

A Missouri jury agreed and awarded Durnell more than $1 million on the failure-to-warn claim, even though the Environmental Protection Agency has ruled glyphosate is not likely to cause cancer in humans. Still, the Missouri Court of Appeals affirmed the verdict and rejected Monsanto’s argument that the Federal Insecticide, Fungicide, and Rodenticide Act expressly pre-empted Durnell’s claim.

Monsanto is a subsidiary of Bayer AG. Monsanto manufactures and distributes Roundup, a glyphosate-based herbicide designed to control weeds.

The case opened the floodgates for lawsuits throughout the country, and Bayer AG has paid billions of dollars to settle cases. Bayer AG said it developed a litigation plan as it sought certainty over labeling requirements.

Bayer AG, on its website, said the decision should provide significant containment of the Roundup litigation. Glyphosate remains the most studied crop protection tool in the world, and the decision affirms that the EPA’s safety determination is the law of the land, ensuring companies cannot be punished under a patchwork of state tort laws for complying with federal labeling requirements.

“This decision is good for American farmers who help feed the world. It provides the regulatory clarity necessary for innovators like us to develop the agricultural tools that guarantee an affordable food supply,” said Bayer CEO Bill Anderson. “This litigation has enormous costs for the company and has impacted public trust. The decision brings overdue justice on an issue that should have been clarified much earlier. It’s time to put it behind us. Strengthened by this ruling, we continue to pursue our multi-pronged containment strategy, which includes the previously announced class settlement.”

The ruling was issued June 25.

The holding in Durnell should result in the dismissal of current warning-based claims and foreclose future claims based on state failure-to-warn theories, which make up the vast majority of claims in the litigation to date.

In February 2026, along with class counsel, Monsanto announced a proposed U.S. nationwide class settlement designed to resolve current and future Roundup claims alleging non-Hodgkin lymphoma injuries through a long-term compensation program. Monsanto previously said the class settlement and Supreme Court strategies were independently necessary and mutually reinforcing elements of the company’s multi-pronged containment strategy. Together with the ruling, the class—which has received preliminary approval—will help ensure Monsanto can significantly contain this litigation.

Agricultural interests have been closely watching the case.

The National Corn Growers Association applauded the decision.

“This is great news for all farmers in the country,” said Jed Bower, an Ohio farmer and National Corn Growers Association president. “Today’s decision reaffirms that FIFRA is the law of the land and states cannot add undue and unproven requirements not backed by science.”

The EPA has repeatedly confirmed that glyphosate does not cause cancer, as have major regulatory bodies around the world, the NCGA said. However, a long series of court cases alleging a failure to warn users of cancer risks, despite the EPA’s repeated conclusion that glyphosate does not cause cancer, has put FIFRA labeling requirements at odds with states’ ability to require additional warnings that conflict with federal findings and labels.

Without the ruling, pesticide manufacturers could have been forced to manage state-based labels that contradict federal findings for products in all 50 states, which likely would have led to increased costs, reduced product availability for farmers and diminished innovation. NCGA highlighted those concerns in an amicus brief submitted to the Supreme Court earlier this year.

The EPA first registered a glyphosate-based product and approved the Roundup label without a cancer warning. The EPA has repeatedly re-evaluated glyphosate and concluded the product is not likely to cause cancer. Monsanto has phased out residential Roundup products that contain glyphosate.

Impact

The holding in Durnell should result in the dismissal of current warning-based claims and foreclose future claims based on state failure-to-warn theories, which make up the vast majority of claims in the litigation to date, Bayer AG said.

In February 2026, along with class counsel, Monsanto announced a proposed U.S. nationwide class settlement designed to resolve current and future Roundup claims alleging non-Hodgkin lymphoma injuries through a long-term compensation program, the company said.

In a dissenting opinion, Justice Ketanji Brown Jackson disagreed with the majority, noting misbranding requirements must still be taken into account.

“Ultimately, the effect of the majority’s interpretation is both remarkable and regrettable, for it unjustifiably closes the courthouse doors to state tort plaintiffs like Durnell,” Jackson said.

Together with the ruling, the class—which has received preliminary approval—will help ensure Monsanto can significantly contain this litigation.

Dave Bergmeier can be reached at 620-227-1822 or [email protected].