Bayer wins Supreme Court case making it harder to sue over glyphosate in Monsanto’s Roundup

The Supreme Court in a 7-2 decision on Thursday said Bayer cannot be sued over state-level claims that the company failed to warn of cancer risks from its weedkiller Roundup and its chemical glyphosate.

The decision is a major win for Bayer and the Trump administration, which argued that failure-to-warn claims were preempted by a federal law that governs pesticides. It’s also a major blow to the Make America Healthy Again movement, which helped return Trump to the White House in the 2024 election but has felt betrayed by the administration’s embrace of glyphosate — the most commonly used weedkiller in agriculture that has long been linked to cancer claims.

Justice Brett Kavanaugh wrote for the majority, arguing that because the Environmental Protection Agency deems glyphosate safe when used properly and has not required a cancer warning label, the Federal Insecticide, Fungicide and Rodenticide Act preempts state-level failure to warn claims.

“As demonstrated by that comprehensive regulatory regime, EPA possesses a variety of tools to learn of and address new safety information,” Kavanaugh wrote. “And as a matter of law, state tort law may not impose labeling requirements ‘in addition to’ or ‘different from’ federal requirements imposed under FIFRA.”

Bayer celebrated the decision on Thursday, saying it is “good for science, farmers, and industries that depend on regulatory clarity for innovation.”

“It should help significantly contain the Roundup™ litigation after nearly a decade of legal battles. The ruling should result in the dismissal of current warning-based claims and bar future failure-to-warn claims,” the company, which bought Roundup maker Monsanto in 2018, said in a statement.

This story is developing. Please check back for updates.