Supreme Court Bars State Failure-to-Warn Claims Against Monsanto in 7-2 Ruling

The U.S. Supreme Court ruled Thursday that Monsanto cannot be held liable under state laws for failing to warn consumers about alleged cancer risks on Roundup labels. In the 7-2 decision in Monsanto Co.

V. Durnell, the court found that the Federal Insecticide, Fungicide, and Rodenticide Act preempts such state-court claims. Justice Brett Kavanaugh wrote the majority opinion, joined by Chief Justice John Roberts and Justices Samuel Alito, Sonia Sotomayor, Elena Kagan, Amy Coney Barrett and Clarence Thomas.

Justices Ketanji Brown Jackson and Neil Gorsuch dissented. The Environmental Protection Agency has determined that Roundup is safe when used as directed and does not require a cancer warning on its label. Federal law requires Monsanto to use an EPA-approved label unless the agency approves a change.

John Durnell, a Missouri gardener, sued Monsanto in 2019 after alleging more than 20 years of exposure to the product caused his non-Hodgkin's lymphoma. A jury awarded him $1.25 million in 2023 on the failure-to-warn claim. The Missouri Court of Appeals rejected Monsanto's preemption arguments, and the state supreme court declined review.

Bayer acquired Monsanto in 2018 and no longer sells glyphosate-based Roundup products. The company said the ruling is good for science, farmers and industries that depend on regulatory clarity. It added that the decision should help contain the Roundup litigation after nearly a decade of legal battles.

Bayer is seeking final approval of a $7.25 billion class settlement proposed in February that would require annual payments for up to 21 years if approved by a Missouri state court. The Trump administration filed a brief supporting Monsanto, and President Trump signed an executive order in February aimed at boosting production of glyphosate-based herbicides.