LINCOLN, Neb. (DTN) -- The Supreme Court has ruled that federal law preempts state failure-to-warn laws, handing Bayer a major victory in the ongoing legal saga of glyphosate-based herbicide Roundup.

The court on Thursday held that the Federal Insecticide, Fungicide and Rodenticide Act expressly preempts state-law failure-to-warn claims against Roundup -- meaning injured plaintiffs cannot sue in state court to force a cancer warning that the U.S. Environmental Protection Agency has not required.

"FIFRA expressly preempts Durnell's state-law failure-to-warn claim because the claim would require Monsanto to add a cancer warning to Roundup's label," the court said in its 7-2 opinion.

Cancer victim John Durnell sued the company in Missouri state court in 2019, alleging that his use of Roundup for 20 years caused his non-Hodgkin's lymphoma. A jury awarded Durnell more than $1 million in damages.

"Failure-to-warn claims, like Durnell's claim here, 'are premised on common-law rules that qualify' as labeling requirements because those 'rules set a standard for a product's labeling,'" the majority said in the opinion, written by Justice Brett Kavanaugh.

"EPA's registration determination that Roundup's label needs not include a cancer warning constitutes a federal labeling requirement that cannot be altered by state law, including state tort suits."

Bayer said in a statement that the court's decision will bring clarity to farmers and other industries.

"It should help significantly contain the Roundup litigation after nearly a decade of legal battles," the company said. "The ruling should result in the dismissal of current warning-based claims and bar future failure-to-warn claims. Monsanto (Bayer) will continue to pursue final approval of the class settlement and other elements of its multi-pronged strategy to contain the Roundup litigation."

In March 2026, a state circuit court in Missouri granted preliminary approval to Bayer's proposed $7.3 billion national settlement.

ONGOING CONCERNS FROM OPPONENTS

Opponents of Roundup were quick to point out ongoing concerns about the chemical.

"This Trump-blessed ruling preventing Americans from seeking justice for serious health problems linked to an EPA-approved pesticide means that now, more than ever, we need an EPA that protects people instead of foreign pesticide companies," said Nathan Donley, the Center for Biological Diversity's environmental health science director.

"The disturbing reality is that glyphosate is just the tip of the pesticide iceberg. The EPA has approved hundreds of poisons the agency itself has linked to cancer, and our parents, kids and loved ones are paying for it with their health, sometimes their lives. The need to profoundly reform our industry-captured system of pesticide regulation could not be clearer."

DISSENTING OPINION

In her dissent, Justice Ketanji Brown Jackson said the majority took the wrong approach in looking at federal law in the Roundup case.

"The majority reads into FIFRA a labeling requirement that does not exist, and it reads out of FIFRA the statute's ongoing prohibition on misbranding," Jackson wrote.

"This interpretation cannot be squared with the text of FIFRA or our precedents. 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 continued, "Tort suits can serve as a catalyst -- encouraging pesticide manufacturers to 'keep abreast of all possible injuries stemming from use of their product' and to maintain labels with the necessary and adequate warnings."

Jackson was joined in the dissent opinion by Justice Neil Gorsuch.

MORE ON COURT'S RULING

The court's ruling essentially establishes that companies complying with EPA-approved labels are shielded from state failure-to-warn lawsuits on safety issues.

Justice Clarence Thomas wrote separately in concurring with the court's opinion, expressing concern about the power granted to federal agencies.

Thomas suggests FIFRA itself may be unconstitutional.

"First, the act likely exceeds Congress's authority under the Commerce Clause, which authorizes Congress to regulate 'Commerce among the several states,'" Thomas said.

"This power allows Congress to regulate 'selling, buying and bartering' across state lines. It does not allow Congress to regulate 'agriculture' or 'manufacturing' activities entirely 'separate' from 'commerce.' The act is a 'comprehensive regulatory statute' that appears to regulate more than the Commerce Clause allows. The act 'regulates the use, as well as the sale' of pesticides and 'regulates pesticides produced and sold in intrastate commerce.'"

Thomas said the modern administrative state is the underlying problem.

"If agencies were not exercising core legislative power, especially through schemes that exceed even Congress's powers, there would be far less occasion to address conflicts between agency actions and state law that the Constitution's framers would not have envisioned," Thomas wrote.

TOUGH POSITION

Christopher A. Seeger, proposed class counsel in the Roundup settlement, said the Supreme Court's ruling puts cancer victims in a tough position.

"This Supreme Court ruling wrongly slams the courthouse door on Americans sickened by pesticides and underscores why we negotiated a $7.25 billion settlement that guarantees compensation to Roundup victims regardless of today's decision," he said in a statement to DTN.

"We urge those opposing this agreement, including the attorney who unsuccessfully argued Durnell, to drop their opposition so that tens of thousands of cancer victims no longer have to wait for justice after a decade of delay."

MORE REACTION

The court's ruling is expected to broadly affect agriculture, especially when it comes to products available to combat pests.

The American Soybean Association, one of many groups to join Bayer by filing amicus briefs with the court, said in a statement that state laws have created a "patchwork" that "conflict with EPA-approved" labels.

"Farmers depend on clear, consistent labeling and a uniform regulatory framework to use pesticides safely and responsibly," ASA said.

"The Supreme Court's decision provides much-needed clarity on the role of federal, science-based regulation and reaffirms the value of sound science in the regulatory process. For decades, the U.S. Environmental Protection Agency, along with regulatory authorities around the world, has repeatedly concluded that glyphosate does not pose a cancer risk when used as directed."

The National Corn Growers Association said on Thursday that without the court's intervention, pesticide manufacturers could have "been forced to manage state-based labels that contradict federal findings for all products in all 50 states."

NCGA said that could have led to increased costs and product availability for farmers.

"This is great news for all farmers in the country," said Jed Bower, Ohio farmer and NCGA 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."

For more information on this case, see https://www.dtnpf.com/….

Todd Neeley can be reached at todd.neeley@dtn.com

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