Monsanto Co. v. Durnell, Case No. 24-1068 (U.S. Supreme Court June 25, 2026)
John Durell sued Monsanto in Missouri state court under a failure-to-warn tort theory, alleging that the company should have included a warning on Roundup’s label indicating that it may cause cancer. A jury awarded Durnell more than $1 million on his state-law failure-to-warn theory. Following trial, Monsanto moved for judgment notwithstanding the verdict, arguing that the Federal Insecticide, Fungicide, and Rodenticide Act (“FIFRA”) expressly preempts Durnell’s claim because it prohibits states from imposing labeling requirements in addition to or different from those required under FIFRA. The trial court rejected Monsanto’s argument. The Missouri Court of Appeals affirmed, ruling that Missouri’s failure-to-warn claim does not conflict with FIFRA’s misbranding provisions.
Monsanto petitioned the U.S. Supreme Court for a writ of certiorari, and the Court granted certiorari due to the conflict between federal courts of appeals and state courts over whether FIFRA preempts state tort claims based on the lack of a cancer warning on Roundup products’ labels.
The Florida Justice Reform Institute joined the American Tort Reform Association, Toxicology Excellence for Risk Assessment, Center for Truth in Science, International Society for Regulatory Toxicology and Pharmacology, Civil Justice Association of California, Pennsylvania Coalition for Civil Justice Reform, New Jersey Civil Justice Institute, and Illinois Coalition for Legal Reform in filing an Amicus Brief in support of Monsanto. The amici argued that pesticide labeling requirements should not be determined based on the incomplete and imprecise studies issued by the International Agency for Research on Cancer (“IARC”), but by standardized and trustworthy Environmental Protection Agency (“EPA”) evaluations. Amici’s brief cited flaws in the IARC testing process, potential conflicts of interest underlying IARC’s methodology, and the strengths of EPA’s pesticide evaluations, among other factors, to support its argument.
In a 7–2 Monsanto v. Durnell Opinion, the Supreme Court reversed the Missouri Court of Appeals’ decision and clarified that FIFRA preempts Missouri’s failure-to-warn cause of action. The Court held that FIFRA requires companies to use labels previously approved by the EPA. The Court further explained that if a label warns of hazards not identified by EPA—and therefore deviates from the EPA-approved label—the company may be liable for misbranding. To include such a warning, a company must first seek approval from EPA. The Missouri failure-to-warn claim conflicts with FIFRA because using the EPA-approved label produced liability under the state law: Monsanto would be required to choose between (1) including an additional warning to comply with Missouri state law, but in so doing violating FIFRA’s requirements; or (2) complying with FIFRA, but in so doing violating Missouri state law. The Supreme Court therefore held that FIFRA expressly preempts the Missouri state law because it introduces labeling requirements “in addition to or different from” the federal labeling requirements under FIFRA.
The Florida Justice Reform Institute was represented by Cary Silverman of Shook, Hardy & Bacon L.L.P. and H. Sherman Joyce and Lauren Sheets Jarrell of the American Tort Reform Association.
