Supreme Court ruling blocks thousands of lawsuits against maker of Roundup weedkiller

The US Supreme Court delivered a monumental victory to Bayer, the pharmaceutical and agricultural giant behind Roundup weedkiller, by blocking thousands of lawsuits alleging its product caused cancer due to inadequate warnings. In a 7-2 decision on June 25, 2026, the Court ruled in Monsanto Co. v. Durnell, asserting that federal pesticide law overrides state-level 'failure-to-warn' claims, a move expected to significantly curb Bayer multi-billion-dollar legal exposure. This landmark ruling for the former Monsanto company, acquired by Bayer in 2018 for $63 billion, is a crucial turning point in a protracted legal battle that has already cost the company billions in settlements. At the heart of the decision is the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), which the Court agreed preempts state requirements, given the Environmental Protection Agency (EPA) approved Roundup label and maintains that glyphosate, its active ingredient, is 'not likely to be carcinogenic to humans'. This decision notably overturned a $1.25 million jury verdict for plaintiff John Durnell, who claimed his non-Hodgkin lymphoma was caused by Roundup. While the ruling provided an immediate surge to Bayer stock, which jumped as much as 19%, the company isn't entirely out of the woods. It's still pursuing a separate proposed $7.25 billion class action settlement to address other existing and future claims, highlighting the complex and ongoing nature of the litigation. Furthermore, the EPA itself faces an October 1, 2026 deadline to reassess glyphosate safety, especially in light of a recent retraction of a 25-year-old study that had been cited to support its safety. This future review keeps the debate over glyphosate health impacts and regulatory oversight firmly in the spotlight.