Bayer wins Roundup cancer trial as jury rejects claims from three women

On October 29, 2026, a St. Louis jury unanimously ruled in favor of Bayer unit Monsanto, rejecting design-defect and negligence claims brought by three women who alleged Roundup weedkiller caused their non-Hodgkin lymphoma. The verdict marks the first trial test since a June 2026 U.S. Supreme Court ruling blocked failure-to-warn lawsuits. Following the decision, Bayer shares rose up to 5.2%, boosting its efforts to finalize a $7.25 billion settlement covering approximately 65,000 pending U.S. claims.

St. Louis lawsuit and trial verdict

• ▪A jury unanimously ruled in favor of Bayer unit Monsanto in a lawsuit alleging Roundup weedkiller caused cancer in three women
• ▪Plaintiffs Theresa Aretino, Cynthia Fernandez, and Betty Larkin filed suit against Monsanto in 2020, alleging that regular use of Roundup weedkiller caused them to develop non-Hodgkin lymphoma
• ▪The St. Louis jury rejected the plaintiffs' claims that Roundup weedkiller was defectively designed, unreasonably dangerous, and sold negligently by Monsanto

Impact of Supreme Court ruling

• ▪Bill Dodero, Bayer's U.S. general counsel, stated that the October 29, 2026 St. Louis verdict demonstrates significant challenges for plaintiffs pursuing Roundup claims following the June 2026 Supreme Court decision
• ▪In June 2026, the U.S. Supreme Court ruled that federal law requires herbicide makers to use Environmental Protection Agency-approved labels, effectively blocking failure-to-warn claims against Bayer

Bayer stock price response

• ▪The stock gain on October 30, 2026 extended Bayer AG's year-to-date share price increases to nearly 35 percent
• ▪Following the October 29, 2026 St. Louis Roundup trial victory, Bayer AG shares rose up to 5.2 percent in European morning trading on October 30, 2026

Analyst and investor reactions

• ▪Union Investment portfolio manager Markus Manns characterized the October 29, 2026 St. Louis verdict as one of Bayer's most important trial wins
• ▪Jefferies analysts noted that the October 29, 2026 St. Louis verdict provided a positive initial datapoint regarding plaintiffs' remaining legal arguments in the Roundup litigation

Bayer's broader Roundup legal liabilities

• ▪Bayer Chief Executive Officer Bill Anderson pledged to significantly contain the company's U.S. legal overhang by the end of 2026
• ▪Bayer inherited extensive Roundup legal liabilities following its 2018 acquisition of Monsanto, incurring costs exceeding $10 billion to $11 billion in legal settlements
• ▪Bayer continues to face approximately 65,000 pending Roundup lawsuits in U.S. state and federal courts

Regulatory and scientific findings on glyphosate

• ▪The International Agency for Research on Cancer classified glyphosate as probably carcinogenic to humans in 2015, a finding Bayer maintains is an outlier based on flawed methodology
• ▪The U.S. Environmental Protection Agency concluded that Roundup weedkiller's label does not require a cancer warning, determining that glyphosate is probably not carcinogenic