Bayer: Why so many Roundup weedkiller lawsuits?

Bayer: Why so many Roundup weedkiller lawsuits? June 26, 2026Bayer is still grappling with tens of thousands of lawsuits over its glyphosate-based weedkiller Roundup, which plaintiffs claim causes cancer, primarily non-Hodgkin lymphoma. Germany's agrochemicals giant inherited the legal mess after taking over Monsanto, the company that produced Roundup, in 2018. Farmers, landscapers and gardeners — mostly based in the United States — argue that Monsanto knew, or should have known, about the risks but failed to provide adequate warnings on product labels. According to the Lawsuit Information Center, Bayer has so far paid out around $11 billion (€9.65 billion) to settle roughly 100,000 cases. Around 61,000 to 65,000 claims remain active. The company has cited decades of scientific studies and regulatory research showing that glyphosate is safe and does not cause cancer. Bayer, which is among the top firms listed on the Frankfurt stock exchange, has won several legal cases, but it has also been hit with several high‑profile losses. What did the US Supreme Court rule? On Thursday, the top US court delivered a major victory to Bayer, ruling that claimants cannot sue the company in state courts over the lack of cancer warnings on the weedkiller. The justices decided 7-2 that, as US federal regulators do not require a warning on products containing glyphosate, individual states cannot force companies to add one. The case centered on a gardener, John Durnell from St Louis, Missouri, who won $1.25 million in compensation after blaming Roundup for his cancer. The Missouri Court of Appeals ruled that Bayer had to comply with state law. The Supreme Court, however, ruled Thursday that Federal law, which governs pesticides, takes priority. Durnell’s lawsuit became the key test case for thousands of other claims in state courts, even though the US Environmental Protection Agency (EPA) had signed off on Roundup's labels. In 2019, the EPA wrote to glyphosate producers telling them that adding a cancer warning would be "false and misleading." This effectively barred Bayer from adding the warning, even when required to by state regulators. The company, which is headquartered in Leverkusen, western Germany, argued it should not be punished for following federal rules. In a statement after the Supreme Court ruling, Bayer said that glyphosate remains the "most studied crop protection tool in the world," adding that the decision "affirms that the EPA’s safety determination is the law of the land." Will the ruling end the lawsuits against Bayer? No. This latest ruling removes just one key type of claim against Bayer, specifically failing to follow state laws and add a cancer warning on Roundup labels. Although the remaining "failure-to-warn" claims are now blocked from proceeding, most remaining lawsuits make other accusations. These include negligence, misleading marketing about Roundup’s safety and selling a defective product. Bayer is expected to argue that the Supreme Court’s decision should also weaken or dismiss these remaining claims. The company has proposed a $7.25 billion settlement to resolve tens of thousands of current and future cases. What does the ruling mean for Bayer? The ruling is a significant win for Bayer, bringing it closer to ending a long and costly chapter in the company's history. It will likely make it much easier to dismiss or settle many of the remaining lawsuits, reducing legal uncertainty that has hurt Bayer's reputation for years. Bayer CEO Bill Anderson acknowledged in a company statement that: "This litigation has enormous costs for the company and has impacted public trust." Although the legal woes have not hurt sales of its weedkiller, the massive cash payouts have hurt profitability and research and development. Bayer has also taken on additional debt to settle the claims. In its statement, the pharmaceutical-crop sciences giant said the billions spent fighting the lawsuits "could have funded the next generation of sustainable crop protection tools, breakthrough therapies, or other advances that farmers, consumers and patients urgently need." Thursday's decision is expected to save Bayer billions in potential future compensation payouts, with the cost of settling many of the remaining cases expected to drop. Bayer’s share price rose sharply after the decision — more than 18% at one point — reflecting investor relief. Who has criticized the ruling? In their dissent, Supreme Court Justices Ketanji Brown Jackson and Neil Gorsuch warned that the majority had broken with the “near-unanimous view” of state and federal courts that had previously rejected Bayer’s pre-emption argument. They added that the outcome left Durnell without any remedy for the “significant harms” he had suffered. Lawyers for many of the plaintiffs said the ruling was a blow for victims, adding that it shuts off a key avenue for justice and compensation. Public health advocates also expressed their anger, including the "Make America Healthy Again” movement, which wants to rein in pesticide use. "Never in history has an administration so blatantly and willingly sold out our fertility, vitality, and health to corporate interests," wrote the movement's Kelly Ryerson, also known as Glyphosate Girl, on X. "It is unforgivable. We will make sure all voters know exactly how this domestic chemical attack happened." The Trump administration had filed a Supreme Court brief, siding with Bayer. In February, Trump also issued an executive order to safeguard US production of glyphosate-based herbicides like Roundup on national security grounds.