The Supreme Court is poised to decide the fate of Bayer’s ongoing glyphosate litigation “Monsanto Company v. Durnell,” with oral arguments for the case scheduled to start today, Monday, April 27, 2026. The outcome is expected to significantly impact Bayer’s strategy for resolving roughly 65,000 outstanding Roundup lawsuits. The case focuses on whether federal pesticide labeling law (FIFRA) preempts state-level failure-to-warn lawsuits, potentially deciding the fate of tens of thousands of pending cancer claims against Roundup.
In an elementary overview… Bayer (the owner of Monsanto) argues that because the EPA has concluded glyphosate is unlikely to cause cancer and does not require a warning label, state law claims demanding such a warning are invalid. The lawsuit stems from John Durnell, a Missouri man who won a $1.25 million verdict after alleging Roundup caused his non-Hodgkin’s lymphoma. The Supreme Court is reviewing the case following the Missouri Court of Appeals upholding the verdict in early 2025. A win for Bayer could effectively end most outstanding Roundup cancer litigation, while a loss could open the company to further billions in damages. A decision on the merits is expected by the end of the Court’s term in June 2026.
Interestingly, Syngenta announced last month that it will stop producing the weedkiller “paraquat” globally by the end of June, with the company citing “significant competition from generic producers around the world.” The end of production also comes as Syngenta faces a slew of lawsuits alleging that paraquat causes Parkinson’s disease. While Syngenta’s competitors will continue to make the chemical, it is now facing new regulatory hurdles here in the US.
Paraquat has been around for some 140 years now. It was first synthesized in 1882 as a dye and redox reagent. Scientists at Imperial Chemical Industries (ICI) in the UK discovered paraquat’s herbicidal properties in 1955, and by the 1960s, it was being used to control weeds in US orchards and around industrial sites. It later emerged as a burndown contact herbicide, and played a key role in the development of no-till farming.
Paraquat’s popularity began to plummet in the 1990s when “glyphosate” was introduced. By that time, the US Environmental Protection Agency (EPA) had classified all paraquat products as restricted-use pesticides, so it was already the less convenient choice. The US Geological Survey (USGS), which last published data on annual agricultural paraquat use in 2018, estimates that more than 17 million pounds of paraquat was applied that year on farmland. In more recent years, there are some indications that farmers may be giving paraquat another look as glyphosate resistance has intensified.
Syngenta framed its move to end paraquat production primarily as a commercial decision, citing intense competition from generic manufacturers that has eroded its competitiveness, and noting that paraquat accounts for less than 1% of its global sales. The product itself has long since gone off patent and is now a generic active ingredient registered for sale by hundreds of companies worldwide, with the largest share concentrated in China.
At the same time, paraquat has been the subject of numerous lawsuits that allege the chemical is linked to Parkinson’s disease. The high-profile lawsuits have helped elevate calls by Parkinson’s support groups and health and environmental advocacy organizations to ban the chemical, and found responsive lawmakers among the Make America Healthy Again (MAHA) movement.
Lawmakers in at least nine states are now considering full or partial bans of paraquat, including Minnesota, Missouri, Pennsylvania, and Vermont. In January, EPA Administrator Lee Zeldin announced that the agency planned to re-evaluate the safety of paraquat. However, the Trump administration has since tried to downplay it as a routine review of “new evidence,” a process that could take as long as four years.
It’s worth noting that paraquat is hardly the only agricultural chemical battling to remain in circulation. Local lawmakers across the country are considering bans or extreme restrictions on widely used crop chemicals like glyphosate and neonicotinoid insecticides, as well. Additionally, the EPA is being sued (again) over its glyphosate policy.
Even if local and national rules remain unchanged, there are concerns that all the lawsuits that keep being brought against chemical makers is adding risks that manufacturers may decide are not worth it, especially lower-margin products that are now off-label. The Supreme Court could soon decide the fate of Bayer’s ongoing glyphosate litigation, which would have wider implications for the crop chemical industry. If Bayer prevails, it would essentially end all state “failure-to-warn” lawsuits against Roundup’s glyphosate-related cancer risks. This would effectively wipe out thousands of pending claims, and set a precedent that shields pesticide manufacturer from litigation so long as the EPA approved its label. Stay tuned… (Sources: AgTechNavigator, No-Till Farmer, SouthernAgToday, Legal Planet)