U.S. Supreme Court 7-2 Ruling Blocks State Roundup Cancer Lawsuits Against Bayer

On June 25, the nation’s highest judicial body issued a 7-2 decision holding that German pharmaceutical giant Bayer cannot be sued at the individual state level over claims that it failed to properly warn consumers of the cancer risks connected to its herbicide Roundup. Bayer owns Monsanto, the company that manufactures Roundup.

The Supreme Court ruled in Bayer’s favor, determining that federal pesticide regulations supersede state-level legal claims related to Roundup, the leading brand name for the herbicide glyphosate. The U.S. Environmental Protection Agency (EPA) does not mandate that glyphosate-containing products carry a cancer warning, and Bayer has consistently followed the agency’s labeling rules for its top-selling herbicide.

The case that reached the Supreme Court was brought by John Durnell, a Missouri resident who alleges that two decades of regular exposure to Roundup caused him to develop non-Hodgkin’s lymphoma, a type of blood cancer. Durnell won an initial state lawsuit against Monsanto in 2019, arguing that the product was legally required to carry a label warning of cancer risks. After multiple rounds of appeals, the case was elevated to the nation’s highest court.

In the majority opinion, the court sided with Monsanto on the grounds that federal law takes priority over the state statute Durnell’s lawsuit relied on, and that the claim is “expressly pre-empted” by federal regulation. Only Justices Ketanji Brown Jackson and Neil Gorsuch dissented from the ruling.

Writing for the majority, Justice Brett Kavanaugh noted: “Importantly, EPA’s regulations require a pesticide manufacturer such as Monsanto to use the EPA-approved pesticide label—here, the Roundup label without a cancer warning—unless and until EPA approves or requires a different label.”

Per the court’s final holding, because the EPA regulates pesticides under the federal law known as the Federal Insecticide, Fungicide, and Rodenticide Act, individual states cannot impose their own additional or replacement warning labels on products like Roundup that comply with federal requirements.