Bayer Wins in SCOTUS Ruling that FIFRA Preempts Lawsuits

Last week, in a 7-2 ruling led by Supreme Court Justice Brett Kavanaugh, the court ruled in favor of Bayer, which owns Monsanto, holding that states cannot require more information on pesticide labels than is required by federal regulations. The case affirmed that FIFRA expressly preempts state-law-based failure-to-warn claims when the EPA has made a definitive determination on product safety.

The lawsuit started when John Durnell sued Monsanto in the Missouri state court, alleging that Roundup usage over 20 years caused his non-Hodgkin lymphoma. His claim was a failure-to-warn tort claim in that Monsanto should have included a cancer warning on the label. Durnell was awarded $1.25 million. The Durnell case was brought to the Supreme Court in April 2025 after Monsanto filed a petition.

Bayer argued that state Roundup herbicide lawsuits decided against the company for failing to carry a warning that it may cause cancer are unlawful under federal law because EPA has concluded the product doesn’t pose a risk when used according to its label. Glyphosate, the active ingredient in Roundup, is an important tool for combating yield-strangling weeds and is widely considered safe by experts.

Earlier this year, NAAA joined the Agricultural Retailers Association (ARA) in filing an amicus curiae, or “friend of the court,” brief that outlined the legal and detrimental production implications and impacts that would hit agricultural applicators nationwide should the court have decided that states have the right to overrule EPA’s risk assessment process and write their own label language. 

The recent ruling means that aerial applicators can rely on having a uniform label, based on EPA’s thorough scientific review process, for each product they apply, no matter what state they’re working in. Had the court ruled otherwise, aircraft traveling out of state to assist another ag aviation operation during a pest outbreak could have found themselves applying under an unfamiliar set of restrictions.

In Justice Kavanaugh’s majority opinion, he explained that the EPA “undertakes an extensive review of the pesticide and its proposed labeling,” and “determine[s] that the proposed label includes all warnings necessary and adequate to protect human health and the environment.” Once registered, “the manufacturer is required to use” the label approved by the EPA until it receives approval for a change or the EPA orders a change. The agency, according to Kavanaugh, “possesses a slew of tools to monitor the pesticide market and scientific developments, and thereby ensure that pesticide labels contain appropriate warnings in light of changed circumstances or new information.”

Since it first studied glyphosate-based pesticides in 1974, Kavanaugh continued, the EPA has “repeatedly concluded that glyphosate is not likely to cause cancer” and therefore has not required “pesticides like Roundup to include a cancer warning on their labels.” That means that “as a matter of federal law, Monsanto legally must use a label without a cancer warning unless and until EPA approves or requires a change.”

In a press release issued after the ruling, Bayer commented, “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.”

The release continued, “For years, American farmers have operated under a cloud of legal uncertainty created not by science, but by the litigation industry. Glyphosate-based herbicides are a foundation of modern, sustainable agriculture. Their safe and effective use supports food security, keeps production costs affordable, makes no-till, sustainable farm practices possible, and allows farmers to do more with less. This ruling restores the regulatory clarity that the agricultural sector, the broader food supply chain, and American consumers deserve after nearly a decade of well-funded attacks by the plaintiffs’ bar. It also provides an opportunity to restore public trust in the scientific consensus on the safety of glyphosate-based herbicides.”