Bayer has filed a petition with the U.S. Supreme Court to review a $1.25 million ruling in a Roundup weed killer after the Missouri Supreme Court already refused to overturn the verdict.
In the petition, filed April 4, Bayer asks the U.S. Supreme Court to limit claims that Roundup causes cancer. The company says consumers should not be allowed to sue for the company not warning Roundup increases the risk of cancer because the U.S. Environmental Protection Agency hasn’t declared such a risk.
The company previously made a similar effort with the Supreme Court, but it was rejected in 2022. But since then, the Third Circuit Court of Appeals agreed with Bayer when it rejected a man’s claim that Bayer subsidiary Monsanto violated state law by not putting a cancer warning on the product.
If the Supreme Court takes up the case, it likely would make filing such lawsuit more difficult.
Bayer filed the petition Friday related to a verdict in state court. John Durnell was awarded the $1.25 million in 2023 by a St. Louis Circuit Court.
Bayer has paid about $10 billion to settle Roundup claims, and it has about $6 billion more set aside for additional cases.
In its Supreme Court petition, Bayer says a split among federal circuit courts in the Roundup personal injury litigation about whether federal law preempts state-based failure-to-warn claims, warrants review.
A Supreme Court ruling also could affect the outcome of thousands of pending cases across the country regarding the question of state-based failure-to-warn claims. Bayer has said it might have to stop selling glyphosate-based products such as Roundup to farmers and other professional users.
Bayer says the Third Circuit was correct when it unanimously said the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) expressly preempted the plaintiff’s failure-to-warn claim, because a jury verdict in his favor would impose labeling requirements different from what EPA requires in administering FIFRA. FIFRA’s express preemption clause declares that a state “shall not impose or continue in effect any requirements for labeling ... in addition to or different from those required’ under federal law.”
In the Missouri case, Bayer says the jury’s verdict “rests solely on the claim that Missouri law requires the company to warn that Roundup is carcinogenic, the precise warning that EPA rejects.”
It says this claim is plainly in conflict with the product label EPA approved under federal law, based on the agency’s rigorous scientific assessment, and cannot be changed without agency approval. Thus, it is expressly preempted.
The 9th and 11th Circuits and Missouri’s intermediate appellate court have reached different conclusions on the preemption question, and the petition argues that state and federal courts require guidance that only the U.S. Supreme Court can provide.
Bayer’s Supreme Court petition also says there is preemption language similar to FIFRA in statutes regulating medical devices, poultry products, meat and motor vehicles that make resolution of this preemption split even more important, as courts often are guided by prior decisions interpreting similar language in other statutes.
Bayer also says the state-based failure-to-warn claim in the Missouri case also should be dismissed under implied preemption because it is impossible for the company to comply with both federal and state requirements for the same reasons already noted.
In October 2023, the St. Louis Circuit Court jury found Bayer failed to warn of the product’s risk and awarded $1.25 million to Durnell, but it rejected all other claims and declined to award punitive damages. The company appealed the verdict in August 2024 and the Missouri Court of Appeals, Eastern District upheld the verdict in February 2025.
Bayer promptly filed a writ to transfer the case to the Missouri Supreme Court and it declined review April 1, making it ripe for U.S. Supreme Court review and the petition filed just three days later.