Bayer has secured a significant legal victory in the United States after a jury rejected claims that its Roundup weedkiller caused cancer in three women, offering the German pharmaceutical giant a measure of relief as it continues efforts to resolve tens of thousands of similar lawsuits.
The unanimous verdict was delivered by a St. Louis jury, marking the first major trial involving Roundup since a US Supreme Court decision in June narrowed the legal arguments available to people alleging that exposure to the herbicide caused cancer.
The outcome could prove important for Bayer as it attempts to defend itself against a massive wave of litigation stemming from its acquisition of Monsanto in 2018. The legal battle has already cost the company billions of dollars and placed sustained pressure on its financial performance and market value.
Bayer is simultaneously seeking judicial approval for a proposed $7.25 billion settlement designed to resolve tens of thousands of outstanding Roundup claims. The proposal is currently being examined by a Missouri state court judge in St. Louis.
The latest courtroom victory comes at a particularly important moment for the company, which is attempting to demonstrate that its legal exposure could become more manageable following the Supreme Court’s intervention.
Bayer shares climbed 4% following the verdict, reaching their highest level in approximately a month.
Markus Manns, a portfolio manager at Germany’s Union Investment, described the decision as one of Bayer’s most significant trial victories. He said the plaintiffs had failed to establish their argument that the company knew about potential risks associated with glyphosate during the product’s development.
Bayer’s US general counsel and global head of litigation, Bill Dodero, also welcomed the decision, arguing that the verdict highlighted the difficulties plaintiffs could encounter when pursuing Roundup claims under the legal framework established by the Supreme Court.
Three women linked prolonged Roundup use to cancer
The lawsuit was originally filed in 2020 by Theresa Aretino, Cynthia Fernandez and Betty Larkin against Monsanto, which is owned by Bayer.
The women alleged that they had regularly used Roundup before being diagnosed with non-Hodgkin lymphoma, a form of cancer affecting the lymphatic system.
Their claims centred on allegations that the weedkiller was defectively designed, posed unreasonable health risks and had been negligently marketed.
Bayer rejected the allegations, maintaining that extensive scientific research conducted over several decades supports the safety of glyphosate, the active ingredient in Roundup.
Larkin died before the trial began. None of the three women was included in Bayer’s proposed settlement programme.
Supreme Court ruling reshapes Roundup litigation
Bayer’s latest victory follows a June decision by the US Supreme Court that significantly changed the legal landscape surrounding Roundup lawsuits.
For years, many plaintiffs had argued that Bayer should have placed cancer warnings on Roundup packaging. The Supreme Court rejected that approach, concluding that federal law requires manufacturers of herbicides to follow the labelling requirements approved by the US Environmental Protection Agency (EPA).
The EPA has not required a cancer warning on Roundup’s label, making it considerably harder for plaintiffs to pursue cases based on the company’s alleged failure to warn consumers.
Bayer has since argued that the Supreme Court’s reasoning should also prevent lawsuits based on other allegations, including defective product design and negligence.
Plaintiffs’ attorneys, however, maintain that those claims remain legally valid and were not eliminated by the court’s decision.
The St. Louis verdict offered Bayer an early indication that its argument could gain traction in subsequent trials.
Scientific debate over glyphosate continues
Despite the courtroom developments, the safety of glyphosate remains a subject of scientific disagreement.
The EPA has previously determined that the chemical is probably not carcinogenic, although the agency is currently conducting another review of its safety.
In contrast, the International Agency for Research on Cancer classified glyphosate as probably carcinogenic to humans in 2015. Bayer has consistently challenged that assessment, describing it as an outlier conclusion based on flawed scientific methodology.
The company continues to face approximately 65,000 lawsuits across US state and federal courts from individuals who claim they developed cancer after using Roundup in residential or occupational settings.
While the latest verdict strengthens Bayer’s position in the courtroom, the much larger legal battle remains unresolved. The proposed $7.25 billion settlement could become a turning point in the company’s effort to contain the litigation, but its approval is still pending.
For Bayer, the challenge now extends beyond winning individual trials: it must convince courts that the remaining claims can be brought under control without allowing the Roundup controversy to continue overshadowing its business.
