US Supreme Court sides with Bayer on Roundup, eliminating failure-to-warn claims in state courts
A 7-2 ruling by the U.S. Supreme Court blocked state-level lawsuits over missing cancer warnings on Roundup weedkiller, handing Bayer a victory that could derail tens of thousands of pending claims.
What the Supreme Court ruled
On June 25, the U.S. Supreme Court ruled 7-2 that federal pesticide regulations preempt state-law claims over the absence of cancer warnings on Roundup labels. The majority opinion, written by Justice Brett Kavanaugh, stated that the Federal Insecticide, Fungicide, and Rodenticide Act "requires uniformity and expressly preempts state labeling requirements." The decision overturned a $1.25 million Missouri jury award to John Durnell, a gardener who developed non-Hodgkin lymphoma and argued that Bayer should have warned about cancer risks.
Federal law requires uniformity and expressly preempts state labeling requirements.
The Environmental Protection Agency had previously determined that glyphosate, Roundup's active ingredient, does not require a cancer warning and had told producers in 2019 that adding one would be "false and misleading." Bayer therefore could not comply with both state demands and federal rules.
What the ruling means for plaintiffs
Roughly 65,000 Roundup lawsuits remain pending in U.S. state and federal courts, according to Bayer and filings. The Supreme Court decision kills failure-to-warn claims, which were central to most suits. Plaintiffs can still pursue other legal theories, including negligent marketing or design defects, but those paths are generally more difficult to prove. Bayer said it would argue that the ruling also undermines those remaining claims.
- IARC classifies glyphosate as probably carcinogenic
- Bayer acquires Monsanto for $63 billion
- EPA tells producers that cancer warning would be false and misleading
- Missouri jury awards John Durnell $1.25 million
- 2000 safety study retracted by regulatory journal
- Bayer announces $7.25 billion proposed nationwide settlement
- U.S. Supreme Court rules 7-2 in favor of Bayer, preempting state failure-to-warn claims
Financial toll and a proposed settlement
Since taking over Monsanto in 2018, Bayer has paid out around $11 billion to settle approximately 100,000 Roundup cases. The company has set aside more than $8 billion for unresolved litigation. In February 2026, Bayer announced a $7.25 billion nationwide settlement that would cover future claims and some not affected by the Supreme Court decision. A decision on finalising that deal is expected by mid-July.
- Paid so far
- 11 USD billions
- Provisioned for pending
- 8 USD billions
- Proposed settlement
- 7.25 USD billions
Bayer welcomed the ruling. A company statement said the decision "should contribute significantly to ending the Roundup litigation after almost a decade of legal battles."
Market reaction
Bayer shares jumped as much as 18.7% on the Frankfurt exchange after the ruling, marking a sharp reversal from earlier pressures that had erased more than two-thirds of the stock's value since the Monsanto acquisition. CEO Bill Anderson had pledged to significantly reduce the legal risk by the end of 2026.
The decision should contribute significantly to ending the Roundup litigation after almost a decade of legal battles.
Background: a decade of disputes
The litigation traces back to a 2015 classification by the World Health Organization's IARC that found glyphosate "probably carcinogenic." Bayer has consistently denied any cancer link, citing regulatory approvals from agencies including the EPA. A 2000 study often used to support Monsanto's safety claims was formally retracted in late 2025. The Durnell case, decided in Missouri in 2023, became the vehicle for Bayer's Supreme Court appeal after the Trump administration supported the company's position that state judges could not override federal labelling rules.
