Roundup / Glyphosate Litigation (Bayer/Monsanto)

Roundup is the most widely used herbicide in the history of agriculture. Introduced by Monsanto in 1974, its active ingredient — glyphosate — became the backbone of modern industrial farming, particularly after the introduction of 'Roundup Ready' genetically modified crops in the 1990s that could survive direct glyphosate application. Global annual glyphosate use now exceeds 1.8 billion pounds.

The litigation erupted after the World Health Organization's International Agency for Research on Cancer (IARC) classified glyphosate as 'probably carcinogenic to humans' (Group 2A) in March 2015. This classification was based on a comprehensive review of epidemiological studies, animal bioassays, and mechanistic evidence.

Critically, internal Monsanto documents obtained during litigation — collectively known as the 'Monsanto Papers' — revealed a systematic corporate effort to manipulate scientific research and regulatory review. Documents showed Monsanto scientists ghostwriting academic papers that appeared under the names of independent researchers, orchestrating coordinated attacks on IARC and its scientists, and strategizing to influence EPA reviews of glyphosate safety. These internal communications have been central to jury decisions in every trial that has proceeded to verdict.

Bayer acquired Monsanto in June 2018 for $63 billion, just weeks before the first Roundup trial verdict. The acquisition has proven catastrophic for Bayer's balance sheet, with the company committing over $11 billion to settlements while its stock price has declined by more than 70% since the acquisition.

Over 100,000 plaintiffs — including farmers, landscapers, groundskeepers, nursery workers, and residential gardeners — have filed claims alleging that their Roundup exposure caused Non-Hodgkin's lymphoma (NHL), a group of blood cancers affecting the lymphatic system. The cases span both the federal MDL in the Northern District of California and state courts across the country, with particularly large state dockets in Missouri and California.

The scientific debate around glyphosate and cancer is among the most consequential in regulatory toxicology and has become a central battleground in the litigation.

IARC's 2015 classification of glyphosate as 'probably carcinogenic to humans' (Group 2A) was based on 'sufficient evidence' of carcinogenicity in experimental animals and 'limited evidence' in humans, plus 'strong' mechanistic evidence including genotoxicity and oxidative stress. The classification reviewed all publicly available scientific literature, including long-term animal studies showing statistically significant tumor increases and human epidemiological studies showing associations between glyphosate exposure and NHL.

Key epidemiological evidence includes the Agricultural Health Study (AHS) — a prospective cohort study of over 50,000 licensed pesticide applicators in Iowa and North Carolina, one of the largest studies of pesticide exposure and health ever conducted. A 2019 meta-analysis published in Mutation Research found a 41% increased risk of NHL among individuals with the highest levels of glyphosate exposure (OR 1.41, 95% CI 1.13-1.75).

A major new two-year study published in Environmental Health in 2025 found that glyphosate caused multiple cancers in laboratory rats even at doses considered 'safe' under current regulatory standards, adding significant new evidence to the causation debate.

The EPA has maintained that glyphosate is 'not likely to be carcinogenic to humans,' though a federal court vacated portions of this assessment in 2022, finding the EPA had not adequately considered available evidence. The scientific disagreement between IARC and EPA — and the Monsanto Papers' revelation that Monsanto worked to influence the EPA's review — has itself become a central issue in litigation.

Areas of ongoing debate include the role of glyphosate versus surfactants and other ingredients in Roundup formulations, and whether the epidemiological evidence, while statistically significant, demonstrates a strong enough association to establish causation for individual cases.

Eligible individuals may include those who regularly used Roundup or other glyphosate-based herbicides in occupational or residential settings and were subsequently diagnosed with Non-Hodgkin's lymphoma or related lymphatic cancers. This encompasses:

• Agricultural workers and farmers who used Roundup on crops • Commercial landscapers and lawn care professionals • Municipal and institutional groundskeepers • Nursery and greenhouse workers • Golf course maintenance workers • Homeowners who used Roundup regularly for lawn and garden maintenance

Exposure periods of several years are typically documented in cases that have proceeded through litigation. Residential users with regular, repeated exposure may have claims alongside occupational users.

This eligibility information is general and informational only. Whether you have a viable legal claim depends on the specific facts of your situation and the laws of your jurisdiction. Consult a licensed attorney.

Supreme Court ruling: On June 25, 2026, the U.S. Supreme Court decided Monsanto Co. v. Durnell, holding 7–2 that the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) expressly preempts state-law failure-to-warn claims that would require a cancer warning on Roundup's EPA-approved label. The decision removes the failure-to-warn theory behind many verdicts; it did not decide other theories such as design defect.

Class settlement: Bayer's proposed $7.25 billion class settlement, which would cover current and future non-Hodgkin's lymphoma claims over 21 years, received preliminary approval from a Missouri circuit court in March 2026. As of late September 2026 it was still under review for final approval.

Remaining claims: Bayer faces about 65,000 remaining claims in state and federal courts, and 3,925 cases were pending in the federal MDL (No. 2741, Judge Vince Chhabria) as of September 1, 2026. A St. Louis trial of three plaintiffs who opted out of the class settlement began on September 29, 2026, testing design-defect claims after the Supreme Court ruling.

Earlier trial verdicts of $175 million, $332 million, $2.25 billion and $2.1 billion were entered in 2023–2025, though awards are typically reduced substantially on appeal.

Bayer AG, which acquired Monsanto in 2018, has mounted a multi-pronged defense. The company argues that glyphosate is one of the most thoroughly studied agricultural chemicals in history and that regulatory agencies worldwide — including the EPA, European Food Safety Authority (EFSA), and the Australian Pesticides and Veterinary Medicines Authority — have concluded it is not carcinogenic when used as directed.

Bayer has particularly emphasized the EPA's 2020 interim decision that glyphosate is 'not likely to be carcinogenic to humans,' arguing that this federal determination should preempt state-law failure-to-warn claims. In June 2026, the Supreme Court accepted this preemption argument for failure-to-warn claims in Monsanto Co. v. Durnell.

Regarding the Monsanto Papers, Bayer has argued that the documents have been taken out of context and that Monsanto's engagement with the scientific community and regulatory agencies was standard industry practice. Critics note that ghostwriting academic papers and orchestrating attacks on WHO scientists go well beyond standard practice.

In 2023, Bayer reformulated U.S. residential Roundup products to remove glyphosate — a decision the company characterized as a business strategy to reduce litigation risk rather than an acknowledgment of safety concerns. Agricultural Roundup products continue to contain glyphosate.

Bayer's total Roundup-related expenditures — including settlements, legal costs, and restructuring charges — have exceeded $16 billion, making it one of the most expensive product liability episodes in corporate history.

Bayer has committed over $11 billion to Roundup-related settlements and litigation costs, resolving approximately 100,000 individual cases.

In March 2026, a Missouri court granted preliminary approval to a $7.25 billion class settlement covering current and future claims. Final approval was still pending in late September 2026, and some plaintiff firms objected to the deal and its opt-out process.

The first three bellwether trials established the litigation's early value: • Johnson v. Monsanto (2018): $289 million verdict (reduced to $20.5 million on appeal) • Hardeman v. Monsanto (2019): $80 million verdict (reduced to $25 million) • Pilliod v. Monsanto (2019): $2 billion verdict (reduced to $86.7 million)

Phase 1 settlement values reportedly ranged from $100,000 to $160,000 per case. The June 2026 Supreme Court preemption ruling is expected to reduce the value of claims that rely on failure-to-warn theories.

Past settlement amounts are not a guarantee of future results. Individual claim values vary significantly based on diagnosis, exposure duration, and case-specific evidence.