Bayer Stock Soars After Supreme Court Guts Core Legal Theory Behind 1000s Of Roundup Cases

Bayer AG shares soared in Frankfurt on Thursday morning after the Supreme Court sided with the German pharmaceutical and life sciences giant in a major Roundup ruling expected to block thousands of lawsuits alleging it failed to warn consumers that the weedkiller could cause cancer.

Bloomberg reported that the Supreme Court voted 7 - 2 to throw out a $1.25 million jury verdict won by Missouri resident John Durnell, who blamed years of Roundup exposure for his non-Hodgkin's lymphoma.

The first opinion is in Monsanto v. Durnell. The court holds that the federal law governing pesticide labels bars a lawsuit against Monsanto, the maker of Roundup weedkiller, for failing to include a warning on the label about the risks of cancer.https://t.co/cPzdF5lgH5

— SCOTUSblog (@SCOTUSblog) June 25, 2026

Justice Brett Kavanaugh wrote for the majority that federal law "demands" uniform pesticide labels and that the state-law "failure-to-warn" claim at issue in the case "would require a cancer warning on Roundup's label, a requirement 'in addition to' and 'different from' the label required by EPA."

Justices Ketanji Brown Jackson and Neil Gorsuch dissented.

NEWS: The Supreme Court just gutted the central legal theory behind tens of thousands of Roundup cancer lawsuits.

In a 7-2 ruling in Monsanto v. Durnell, the justices held that federal pesticide law preempts state "failure-to-warn" claims, meaning a jury can't punish Bayer-owned… pic.twitter.com/zrIsgJDBu5

— Benjamin Ryan (@benryanwriter) June 25, 2026

The ruling is a major milestone in Bayer's years-long court battle over Roundup, which it acquired from Monsanto for $63 billion in 2018. The company has since stopped using glyphosate in Roundup products sold at major retailers.

Earlier this year, Bayer announced a proposed $7.25 billion class action settlement to resolve tens of thousands of current and future lawsuits.

Shares of Bayer soared 20%...

...marking the largest intraday gain since March 2003.

Bloomberg Intelligence analyst Holly Froum wrote in a note before the high court ruling that about $787 million in existing Roundup verdicts could be affected by the decision.

To sum up, the high court ruled that consumers cannot sue Bayer over the absence of a cancer warning on Roundup labels because federal regulators had already concluded that such a warning was not required.