Supreme Court Reinforces EPA’s Primary Role in Pesticide Labeling in Monsanto v. Durnell
On June 25, 2026, the U.S. Supreme Court held in Monsanto Co. v. Durnell that the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) expressly preempts certain state-law failure-to-warn claims. Specifically, such a claim is preempted if its premise is that a pesticide label was deficient because it did not include a health-related warning that the U.S. Environmental Protection Agency (EPA) had determined was not required based on the EPA's assessment of the data related to the product.
While the decision has attracted attention due to its connection to high-profile glyphosate litigation, the Court’s reasoning is best understood as an application of FIFRA’s express preemption provision regarding pesticide labeling. Durnell does not insulate pesticide manufacturers from all potential liability in connection with their products. Rather, Durnell confirms that when Congress amended FIFRA in 1988, it assigned EPA primary authority over labeling content.
One likely outcome of Durnell is that there will be even more scrutiny of EPA’s reviews of pesticides. Below, we discuss the Durnell decision, as well as the Trump Administration’s broader policy focus on pesticides.
Background
Durnell arose from a Missouri state court action brought by a plaintiff who alleged that long-term exposure to Monsanto’s Roundup herbicide (and its active ingredient, glyphosate) caused him to develop non-Hodgkin’s lymphoma. The plaintiff asserted, among other claims, that Monsanto failed to warn consumers of cancer risks by omitting a warning from its product label. A Missouri jury agreed, awarding more than $1 million in damages based on a failure-to-warn theory.
EPA (along with regulators in Canada, Australia, Japan, and the European Union) have concluded that glyphosate is “not likely to cause cancer,” and therefore has not required cancer warnings on Roundup labels. Monsanto argued that FIFRA preemption insulated it from state law tort claims that would, in effect, require a warning that EPA did not require to be on the product label. The Missouri Court of Appeals rejected the preemption argument. Several other glyphosate-failure-to-warn cases were also decided by various U.S. Courts of Appeals, with mixed results on the preemption question.
The Supreme Court granted certiorari to resolve whether FIFRA preempts such state-law failure-to-warn claims.
The Supreme Court’s Decision
In a 7-2 decision authored by Justice Kavanaugh, the Court held that FIFRA expressly preempts the respondent’s failure-to-warn claim. Key aspects of the Court’s analysis include:
- Textual Interpretation of FIFRA’s Preemption Clause. The Court grounded its analysis in FIFRA’s express preemption provision, which bars states from imposing any labeling or packaging requirements “in addition to or different from” those required under federal law. The majority found this language unambiguous and dispositive. Because EPA had approved Roundup’s label without a cancer warning, the Court reasoned that a state-law verdict premised on the absence of such a warning effectively imposes a new labeling requirement. In the majority’s view, it did not matter that the requirement arose through tort law rather than statute or regulation; what mattered was the practical effect of the verdict – i.e., compelling the manufacturer to alter its label in a manner inconsistent with the label the EPA approved and requires.
- Role of EPA in Determining Labeling Requirements. The Court emphasized the comprehensive nature of FIFRA’s regulatory scheme and EPA’s central role within it. Under FIFRA, and EPA’s implementing regulations which the Court recognized “give content to FIFRA’s misbranding standards,” EPA must review and approve pesticide labels as part of the registration process, ensuring that they contain all warnings necessary to protect human health and the environment and do not include false or misleading statements. The Court stressed that manufacturers are legally obligated to comply with EPA-approved labeling and cannot unilaterally modify those labels without agency approval. Allowing juries to impose additional warning requirements, the Court explained, would effectively permit state-by-state second-guessing of EPA’s expert determinations and undermine the statute’s goal of national uniformity.
- Rejection of the “Parallel-to-FIFRA” Argument. The Court rejected the argument that state failure-to-warn claims merely “parallel” FIFRA’s standard as framed at too high a level of generality. Instead, the Court emphasized that FIFRA’s preemption analysis must focus on the specific labeling requirements imposed through EPA’s registration decisions, not abstract duties to provide “adequate” warnings. It concluded that EPA’s approval of required safety warnings on a label – combined with regulatory requirements to adhere to that label – constitutes a federal requirement under FIFRA with preemptive force. The majority distinguished a prior case finding no-preemption, Bates, on the ground that it had involved claims about the efficacy of a product (which EPA had not evaluated), rather than safety claims like those at issue in Durnell, which EPA had thoroughly reviewed.
Justice Thomas concurred but wrote separately to raise broader constitutional concerns about FIFRA and the administrative state. He questioned whether the statute exceeds Congress’ authority under the Commerce Clause by regulating not only the interstate sale of pesticides but also their intrastate use, including by individual consumers. He also expressed skepticism about Congress’ delegation of significant policymaking authority to EPA, suggesting that the Agency’s extensive labeling regulations may involve the exercise of core legislative power. Finally, he highlighted unresolved constitutional questions regarding agency-driven preemption, noting the tension between treating agency action as binding federal law and the limits imposed by the Supremacy Clause and separation-of-powers principles.
Justice Jackson, joined by Justice Gorsuch, dissented, arguing that state tort law can complement federal regulation and provide a backstop where federal oversight may be incomplete.
Significance
The immediate impact of Durnell will be felt most acutely in failure-to-warn litigation tied to pesticide labeling, including in ongoing Roundup litigation, with regard to any claims not subject to the pending class action settlement that was announced by Bayer prior to the issuance of the decision in Durnell. Bayer has stated that it will continue to pursue final approval of that settlement notwithstanding the decision in Durnell.
Claims alleging that manufacturers should have included safety warnings not required by EPA will face substantial preemption hurdles. While failure-to-warn claims may be narrowed, other claims that are not tied directly to label content may remain viable, depending on how lower courts interpret the scope of preemption. Plaintiffs may attempt to circumvent Durnell by arguing that a specific label statement central to their claim was not reviewed with the requisite focus by EPA to trigger preemption – i.e., a specific statement is more similar to the efficacy related statements in Bates than the statements in Durnell. Additionally, it is possible that some states may try to pass new legislation that would create causes of action for alleged harms related to pesticides to circumvent Durnell. Any such effort could, of course, be subject to its own preemption challenge.
Continued Momentum in Federal Pesticide Policy
The decision comes at a time of heightened federal activity in the broader pesticide and agricultural space.
Most recently, on July 1, 2026, EPA announced a new national innovation challenge with up to $30 million in prize funding to accelerate the development of cost-effective alternatives to conventional chemical crop desiccation. The initiative is intended to support practical, science-based tools that allow farmers to reduce reliance on pesticides applied close to harvest, while maintaining crop quality and operational efficiency. EPA specifically identified approaches such as improved agronomic practices, mechanical or physical drying methods, biological inputs, and precision agriculture technologies.
Additionally, on the same day as the Durnell decision, the Administration issued an Executive Order (EO) on “Advancing Regenerative Agriculture and Strengthening American Farm Resilience,” which directs federal agencies to expand research into cumulative chemical exposures, promote alternative crop protection tools, and support regenerative farming practices. Among other things, the EO calls for increased interagency coordination on chemical risk assessment and encourages EPA to prioritize review and registration of alternative substances.
This followed other pesticide-focused Executive Orders, including a February 18, 2026 EO on “Promoting the National Defense by Ensuring an Adequate Supply of Elemental Phosphorus and Glyphosate-Based Herbicides,” which invoked the Defense Production Act to ensure the domestic supply of glyphosate-based herbicides and their key inputs. That EO characterizes glyphosate-based products as “cornerstone[s]” of U.S. agriculture and directs federal agencies to take steps to secure and, if necessary, prioritize their production.
Consistent with the policy initiative announced in this Executive Order, on June 30, 2026, Bayer petitioned the U.S. Court of International Trade to impose countervailing duty tariffs on Chinese glyphosate imports, arguing that the imports are being unfairly offered for sale in the United States at below the actual cost of production and thereby harming the U.S. production base.
Conclusion
Durnell is a significant FIFRA-related development, and is one of a large number of U.S. pesticide policy-related developments in the past several months. Companies with questions regarding the implications of Durnell, or any of the Executive Orders or EPA initiatives noted above, should contact one of the authors of this alert or their regular Wiley contact.
