Supreme Court shields Roundup maker from cancer warning lawsuits

The Supreme Court ruled 7-2 that federal pesticide law blocks state failure-to-warn claims seeking a cancer warning on Roundup labels. Justice Brett Kavanaugh wrote the majority opinion in Monsanto Company v. Durnell, Justice Clarence Thomas concurred, and Justice Ketanji Brown Jackson dissented, joined by Justice Neil Gorsuch.

The case came from John Durnell, who sued in Missouri in 2019 after saying he had used Roundup for about 20 years and later developed non-Hodgkin’s lymphoma. A jury awarded him more than $1 million, and the Missouri Court of Appeals upheld the verdict before the Supreme Court reversed. The ruling turns on the Federal Insecticide, Fungicide, and Rodenticide Act, which the court said expressly preempts a state-law claim that would require Monsanto to add a cancer warning to the herbicide’s label.

It shuts down a key legal route that had powered thousands of Roundup cases in state courts, where plaintiffs argued that Bayer and Monsanto should have warned users about glyphosate-related cancer risk. About 170,000 claims are involved, with more than 3,900 still pending in federal court.

Glyphosate has been registered as a pesticide in the United States since 1974, and the Environmental Protection Agency has repeatedly reviewed and reassessed its safety. In March 2015, the World Health Organization’s cancer agency, the International Agency for Research on Cancer, classified glyphosate as probably carcinogenic to humans.

MAHA-aligned activists reacted angrily and said they felt betrayed after the ruling, while the Trump administration backed Bayer in the case. The American Soybean Association praised the decision.

The company has already paid more than $6 billion in verdicts since October 2023, and in February 2026 it announced a proposed $7.25 billion settlement covering current and future claims. A Missouri state court granted preliminary approval on March 4, 2026, with a final approval hearing scheduled for July 9, 2026.