This commentary discusses the case of Monsanto Co. v. Durnell, Certiorari to the
Court of Appeals of Missouri, Eastern District, No. 24–1068, argued
April 27, 2026, and decided June 25, 2026, where the US Supreme Court (SCOTUS) reversed
a $1 million judgment found by a Missouri state court.
Facts of the Case
John Durnell sued Monsanto in Missouri state court, alleging that
his long-term use of Roundup weed killer caused his non-Hodgkin's lymphoma and that
Monsanto should have warned users of cancer risks. A jury awarded Durnell more than
$1 million on a failure-to-warn theory, and the Missouri Court of Appeals affirmed.
SCOTUS granted certiorari to resolve whether the Federal Insecticide, Fungicide, and
Rodenticide Act (FIFRA) preempts the state-law failure-to-warn claim.
Monsanto manufactures and distributes Roundup, a glyphosate-based
herbicide. The Environmental Protection Agency (EPA) has repeatedly evaluated
glyphosate and has concluded that it is not likely to cause cancer; accordingly, the
EPA has not required a cancer warning on Roundup's label.
The case turned on FIFRA, particularly its express preemption
clause, 7 U.S.C. §136v(b). That provision bars states from imposing labeling or
packaging requirements that are "in addition to or different from" those required
under FIFRA. The court also relied on FIFRA's registration and labeling provisions,
EPA regulations governing approved labels, and label changes.
The Court's Ruling
The majority reasoned that EPA's approval of Roundup's label
without a cancer warning created a federal labeling requirement under FIFRA. Because
Monsanto was required to use the EPA-approved label unless the EPA required a
change, a state-law duty requiring a cancer warning would impose a requirement
different from or in addition to federal requirements. SCOTUS concluded that state
tort duties can qualify as labeling requirements and that Durnell's claim would
directly alter what Roundup's label must say.
Durnell argued that his Missouri failure-to-warn claim merely
paralleled FIFRA's misbranding prohibition, which requires adequate warnings and
prohibits false or misleading labels. The majority rejected that view as too
general, emphasizing the EPA's central role in determining pesticide labels and the
statutory goal of uniform labeling.
Analysis
The decision gives a strong preemptive effect to the EPA's label
approval under FIFRA and treats the agency-approved label as more than evidence of
compliance; for preemption purposes, it functions as a federal requirement that
limits inconsistent state tort duties. This approach favors national uniformity in
pesticide labeling and protects manufacturers from state-law liability based on
warnings the EPA has not required.
At the same time, the dissent warned that the ruling narrows the traditional role of state tort suits as a parallel enforcement mechanism and may reduce incentives for manufacturers to seek label changes when new risk information emerges.
Conclusion
SCOTUS reversed the Missouri Court of Appeals and held that FIFRA
expressly preempts Durnell's state-law failure-to-warn claim. Because the claim
would require Monsanto to add a cancer warning to Roundup's label despite the EPA's
approval of a label without such a warning, the state-law duty was deemed "in
addition to" and "different from" federal labeling requirements under FIFRA.
Justice Clarence Thomas concurred to raise broader constitutional
concerns about Congress's commerce power, delegation to agencies, and administrative
preemption.
Justice Ketanji Brown Jackson, joined by Justice Neil M. Gorsuch,
dissented, arguing unsuccessfully that the EPA registration is not itself a binding
labeling requirement and that state claims equivalent to FIFRA's misbranding
prohibition should not be preempted.
Opinions expressed in Expert Commentary articles are those of the author and are not necessarily held by the author's employer or IRMI. Expert Commentary articles and other IRMI Online content do not purport to provide legal, accounting, or other professional advice or opinion. If such advice is needed, consult with your attorney, accountant, or other qualified adviser.
This commentary discusses the case of Monsanto Co. v. Durnell, Certiorari to the Court of Appeals of Missouri, Eastern District, No. 24–1068, argued April 27, 2026, and decided June 25, 2026, where the US Supreme Court (SCOTUS) reversed a $1 million judgment found by a Missouri state court.
Facts of the Case
John Durnell sued Monsanto in Missouri state court, alleging that his long-term use of Roundup weed killer caused his non-Hodgkin's lymphoma and that Monsanto should have warned users of cancer risks. A jury awarded Durnell more than $1 million on a failure-to-warn theory, and the Missouri Court of Appeals affirmed. SCOTUS granted certiorari to resolve whether the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) preempts the state-law failure-to-warn claim.
Monsanto manufactures and distributes Roundup, a glyphosate-based herbicide. The Environmental Protection Agency (EPA) has repeatedly evaluated glyphosate and has concluded that it is not likely to cause cancer; accordingly, the EPA has not required a cancer warning on Roundup's label.
The case turned on FIFRA, particularly its express preemption clause, 7 U.S.C. §136v(b). That provision bars states from imposing labeling or packaging requirements that are "in addition to or different from" those required under FIFRA. The court also relied on FIFRA's registration and labeling provisions, EPA regulations governing approved labels, and label changes.
The Court's Ruling
The majority reasoned that EPA's approval of Roundup's label without a cancer warning created a federal labeling requirement under FIFRA. Because Monsanto was required to use the EPA-approved label unless the EPA required a change, a state-law duty requiring a cancer warning would impose a requirement different from or in addition to federal requirements. SCOTUS concluded that state tort duties can qualify as labeling requirements and that Durnell's claim would directly alter what Roundup's label must say.
Durnell argued that his Missouri failure-to-warn claim merely paralleled FIFRA's misbranding prohibition, which requires adequate warnings and prohibits false or misleading labels. The majority rejected that view as too general, emphasizing the EPA's central role in determining pesticide labels and the statutory goal of uniform labeling.
Analysis
The decision gives a strong preemptive effect to the EPA's label approval under FIFRA and treats the agency-approved label as more than evidence of compliance; for preemption purposes, it functions as a federal requirement that limits inconsistent state tort duties. This approach favors national uniformity in pesticide labeling and protects manufacturers from state-law liability based on warnings the EPA has not required.
At the same time, the dissent warned that the ruling narrows the traditional role of state tort suits as a parallel enforcement mechanism and may reduce incentives for manufacturers to seek label changes when new risk information emerges.
Conclusion
SCOTUS reversed the Missouri Court of Appeals and held that FIFRA expressly preempts Durnell's state-law failure-to-warn claim. Because the claim would require Monsanto to add a cancer warning to Roundup's label despite the EPA's approval of a label without such a warning, the state-law duty was deemed "in addition to" and "different from" federal labeling requirements under FIFRA.
Justice Clarence Thomas concurred to raise broader constitutional concerns about Congress's commerce power, delegation to agencies, and administrative preemption.
Justice Ketanji Brown Jackson, joined by Justice Neil M. Gorsuch, dissented, arguing unsuccessfully that the EPA registration is not itself a binding labeling requirement and that state claims equivalent to FIFRA's misbranding prohibition should not be preempted.
© Barry Zalma 2026
Opinions expressed in Expert Commentary articles are those of the author and are not necessarily held by the author's employer or IRMI. Expert Commentary articles and other IRMI Online content do not purport to provide legal, accounting, or other professional advice or opinion. If such advice is needed, consult with your attorney, accountant, or other qualified adviser.