On June 25, 2026, the U.S. Supreme Court delivered a 7-2 decision in Monsanto Co. v. Durnell, ruling that the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) preempts state-law failure-to-warn claims that would require a pesticide manufacturer to add a cancer warning to an Environmental Protection Agency (EPA)-approved label. This decision effectively shields Monsanto, now owned by Bayer, from numerous lawsuits alleging that its herbicide, Roundup, causes cancer.
The case originated when John Durnell, a Missouri resident, sued Monsanto, claiming that his prolonged use of Roundup led to his development of non-Hodgkin’s lymphoma. Durnell argued that Monsanto failed to warn consumers about the potential cancer risks associated with glyphosate, Roundup’s active ingredient. A Missouri jury awarded Durnell over $1 million in damages. Monsanto appealed, contending that FIFRA preempted Durnell’s state-law claims because the EPA had approved Roundup’s label without a cancer warning, having determined that glyphosate is unlikely to cause cancer. ([supreme.justia.com](https://supreme.justia.com/cases/federal/us/609/24-1068/?utm_source=openai))
Justice Brett Kavanaugh, writing for the majority, emphasized that FIFRA prohibits states from imposing labeling requirements “in addition to or different from” those mandated by federal law. He noted that the EPA’s repeated evaluations concluded that glyphosate does not necessitate a cancer warning, thereby preempting state-level claims that seek to impose additional labeling requirements. ([mayerbrown.com](https://www.mayerbrown.com/en/insights/publications/2026/06/supreme-court-holds-roundup-failure-to-warn-claim-preempted-by-federal-law?utm_source=openai))
Justice Ketanji Brown Jackson, joined by Justice Neil Gorsuch in dissent, argued that the majority’s interpretation undermines the traditional role of states in protecting their citizens from potential harms. She expressed concern that the decision could limit individuals’ ability to seek recourse under state law when federal regulations are perceived as insufficient. ([law.cornell.edu](https://www.law.cornell.edu/supremecourt/text/24-1068?utm_source=openai))
This ruling has significant implications for the agrochemical industry and product liability litigation. By affirming the preemptive power of federal labeling requirements, the Court has set a precedent that may limit the scope of state-law claims against manufacturers whose products comply with federal standards. Legal experts suggest that this decision could influence future cases involving federally regulated products and the balance between federal oversight and state consumer protection laws. ([gtlaw.com](https://www.gtlaw.com/en/insights/2026/6/scotus-holds-fifra-expressly-preempts-state-law-failure-to-warn-claims/?utm_source=openai))
For Bayer, the decision represents a substantial legal victory, potentially mitigating the financial impact of ongoing and future litigation related to Roundup. The company has faced nearly 200,000 legal claims and has paid approximately $10 billion in settlements. The Supreme Court’s ruling may lead to the dismissal of similar lawsuits, providing a measure of relief for the company. ([lemonde.fr](https://www.lemonde.fr/en/economy/article/2026/06/26/us-supreme-court-ruling-could-shield-bayer-from-thousands-of-lawsuits-relating-roundup-to-cancer_6754903_19.html?utm_source=openai))
However, the controversy surrounding glyphosate and its safety profile is likely to persist. While the EPA and other regulatory bodies have deemed glyphosate non-carcinogenic, debates continue within the scientific community and among consumer advocacy groups. The Supreme Court’s decision underscores the complex interplay between federal regulatory authority, state consumer protection efforts, and the rights of individuals to seek legal remedies.