The U.S. Supreme Court has ruled in favor of the manufacturer of the herbicide Roundup in a decision expected to halt thousands of lawsuits claiming the company failed to warn users about the product's potential to cause cancer.
The June 27, 2024 ruling involved a case brought by John Durnell, who was diagnosed with non-Hodgkin lymphoma after years of exposure to glyphosate—the active ingredient in Roundup. The Supreme Court, in a 7-2 vote, overturned a $1.25 million compensation award from a Missouri state court, holding that the company cannot be sued for failure to warn in state courts when federal regulations have concluded the cancer risk is low and do not require a warning label.
Bayer, the German agrochemical giant that acquired Roundup maker Monsanto in 2018 for $63 billion, has faced more than 100,000 lawsuits in state and federal courts. Bayer shares surged nearly 18% after the ruling. The company called the decision “good for science, farmers, and industries that rely on regulatory clarity to innovate” and said it would help end litigation over Roundup. Bayer has also proposed a $7.25 billion settlement to resolve current and future claims.
Conservative Justice Brett Kavanaugh, writing for the majority, noted that the U.S. Environmental Protection Agency (EPA) has determined glyphosate does not cause cancer and does not require a warning label on Roundup. The federal pesticide law, the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), prevents states from imposing different or additional requirements.
However, environmental and health activists criticized the ruling. Tarah Heinzen, legal director of Food and Water Watch, called it a “disaster for public health.” Kelly Ryerson, co-executive director of American Regeneration, warned the ruling would prolong “the cancer epidemic, infertility, and chronic disease in general for generations.”
Liberal Justice Ketanji Brown Jackson, joined by conservative Justice Neil Gorsuch in dissent, called the ruling “remarkable and unfortunate because it improperly closes the courthouse door to plaintiffs like Durnell.”
Durnell sued Monsanto in 2019, alleging the company failed to warn about the dangers of Roundup. He sprayed the herbicide for a neighborhood association in St. Louis for 20 years without protective gear. A jury ruled in his favor in 2023, and a state appeals court upheld the verdict in 2025.
Union Investment fund manager Markus Manns described the ruling as a “milestone” for Bayer, marking a “new era” after a decade of litigation. Bayer awaits approval of its $7.25 billion settlement in July 2024 to fully resolve the matter.
