The case focused on Roundup’s active ingredient, glyphosate, which the EPA considers safe when used as directed|Mike Mozart|CC BY 2.0

The Supreme Court has ruled that Bayer cannot face state lawsuits accusing the company of failing to warn consumers that its popular weedkiller Roundup may cause cancer.

In a 7-2 decision, the court said federal law governing pesticide labels takes priority over state requirements, giving Bayer a major legal victory.

Thousands of cases affected
The case focused on Roundup’s active ingredient, glyphosate, which the Environmental Protection Agency (EPA) deems safe when used as directed.

Since the EPA has never required a cancer warning on glyphosate-based products, the court said states cannot impose different labeling standards through lawsuits.

The ruling overturns a Missouri jury’s award of more than $1 million to a man who claimed repeated exposure to Roundup caused his cancer. It is also expected to affect thousands of similar lawsuits filed against Bayer since its acquisition of Monsanto in 2018.

Bayer, which has already set aside $16 billion to settle Roundup-related cases, said it will continue pursuing its proposed $7.25 billion class-action settlement covering many remaining claims. The company’s shares climbed nearly 16% following the decision.

Critics raise health concerns
The ruling has drawn criticism from health advocates, who argue that consumers deserve stronger warnings about potential cancer risks. They point to a 2015 World Health Organization assessment that classified glyphosate as “probably carcinogenic to humans.”

Two Supreme Court justices dissented, saying the decision weakens consumer protections and departs from the view adopted by many lower courts.