Supreme Court to decide whether federal law preempts Roundup failure-to-warn suits against Bayer

Supreme Court to resolve Roundup preemption fight

The U.S. Supreme Court is agreeing to hear Monsanto Co. v. Durnell on April 27, setting up a high-stakes test of whether federal pesticide labeling law preempts state failure-to-warn claims over the weedkiller Roundup. Bayer AG, which purchased Monsanto in 2018, is appealing a Missouri jury verdict that awarded plaintiff John Durnell $1.25 million after a jury found Monsanto failed to warn him that exposure to Roundup, which contains glyphosate, could have contributed to his non‑Hodgkin lymphoma. A state appeals court upheld the liability ruling and the Missouri Supreme Court declined review, prompting Bayer to seek intervention at the national level.

At the heart of the appeal is a federal preemption argument: Monsanto contends the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) and EPA-approved labeling decisions occupy the field, barring state juries from imposing inconsistent warnings. The U.S. Solicitor General D. John Sauer files a brief siding with Monsanto, warning the court that allowing the Missouri decision to stand could invite juries to second‑guess science-based agency determinations. Plaintiffs’ lawyers counter that Monsanto “has known for decades” about glyphosate risks and marketed Roundup as safe, framing the case as a traditional product-liability dispute about corporate warnings rather than a challenge to federal regulatory judgments.

The Supreme Court’s ruling could reshape liability exposure for Bayer and others in the agrochemical industry by limiting state-court avenues for mass tort claims and steering more disputes into the administrative and federal statutory framework. Thousands of Roundup suits are pending nationwide, and the decision may affect how courts treat scientific assessments by agencies like the EPA versus evidence presented in state tort trials. A win for Bayer would bolster the argument that pesticide safety questions belong primarily to federal regulators; a loss would preserve a broad path for state-law claims and sustain pressure on manufacturers regarding warning disclosures and risk communication.

Science disputes heighten regulatory and legal pressure

The litigation unfolds against conflicting assessments: the World Health Organization’s cancer agency classifies glyphosate as “probably carcinogenic to humans,” while the U.S. EPA has rejected that finding and California listed glyphosate as a carcinogen in 2017. Those divergent positions complicate the legal debate over whether federal regulatory conclusions should preempt state liability claims.

Justices also take up privacy and administrative-law cases

The court schedules other high-profile arguments the same term, including Chatrie v. United States on cellphone location‑history warrants and consolidated FCC v. AT&T and Verizon v. FCC on whether in‑house FCC adjudications and penalties conform with the Communications Act, signaling a term that weighs heavily on administrative authority and individual privacy.