Missouri jury clears Monsanto in first Roundup trial since Supreme Court preemption ruling

A Missouri jury returned a defense verdict for Monsanto on Thursday in the first Roundup trial court decision since the U.S. Supreme Court restricted a major category of failure-to-warn lawsuits — a win for Bayer, which bought Monsanto in 2018 and still faces thousands of similar claims.

The jury ruled for Monsanto within hours of closing arguments. The trial, which began Sept. 30, involved three women from Florida who alleged exposure to Roundup caused their illnesses — non-Hodgkin lymphoma, a cancer of the lymphatic system. During closings, plaintiffs' attorney Greg Dovel of Duvel & Luner sought between $10 million and $30 million for each woman, according to Law.com. The jury gave them nothing.

Why did the legal ground shift?

The verdict follows the Supreme Court's June 25 ruling in Monsanto Co. v. Durnell. The court held that federal pesticide law preempts state failure-to-warn claims when those claims would require warnings beyond what federal regulators mandate. The case turned on the Federal Insecticide, Fungicide, and Rodenticide Act, which governs pesticide registration and labeling. States, the court found, cannot require a cancer warning that conflicts with federal labeling requirements.

That ruling narrows one avenue for plaintiffs. It does not end the litigation. Bayer still defends thousands of suits alleging Roundup exposure caused cancer, and the company has maintained throughout that glyphosate, the herbicide's active ingredient, is safe when used as directed. Outcomes in individual cases will still depend on the specific claims and evidence presented.

Takeaway: the preemption ruling changes what plaintiffs can argue, not whether they can sue at all.

What does the science say?

The dispute sits on top of competing scientific assessments. The Environmental Protection Agency has concluded that glyphosate is not likely to be carcinogenic to humans. The International Agency for Research Cancer reached the opposite-leaning conclusion in 2015, classifying glyphosate as "probably carcinogenic" to humans. EPA's position and its ongoing regulatory review are posted on the agency's glyphosate information page.

Takeaway: regulators and cancer researchers still disagree, and courts are being asked to referee that gap.

How much does one verdict matter?

The Missouri case is an early test of how litigation proceeds after the Supreme Court decision, and Monsanto passed it. But a single jury verdict within hours of closings is a data point, not a trend. The broader significance will depend on how other courts apply the Durnell ruling across the pending docket — and Bayer has given no indication it intends to settle the remaining inventory on the strength of one win.

For growers, the litigation has practical weight: Roundup remains one of the most widely used herbicides in U.S. row-crop production, and any ruling that reshapes liability exposure for its maker can ripple into input availability, labeling and cost over time — though no such shift has occurred yet.

The next signal will come from how courts handle the pending cases under the new preemption standard.