A California State Court of Appeal issued a ruling on August 9, 2021, upholding a jury verdict awarding millions of dollars in damages to a married couple who claimed that exposure to Roundup, a glyphosate-based herbicide, caused them both to develop non-Hodgkin’s lymphoma. This ruling from the appellate court is the latest in a glyphosate lawsuit to consider whether the plaintiffs’ state law failure-to-warn claims were preempted by the Federal Insecticide, Fungicide, and Rodenticide Act (“FIFRA”). Here, the court found that the state law claims were not preempted by FIFRA, a finding that is in line with a ruling from the Ninth Circuit Court of Appeals, but is contrary to a decision from another California State Court of Appeal.


This lawsuit, Pilliod v. Monsanto Co., No. A158228 (Cal. Ct. App. Aug. 9, 2021), was originally filed in a California Superior Court in 2018, and went to trial in 2019. It was the third lawsuit where the plaintiffs alleged that their cancer was the result of exposure to Roundup to receive a jury trial. Similar to other glyphosate lawsuits, the plaintiffs in Pilliod v. Monsanto Co. raised a variety of state law claims in their complaint and at trial. Those claims include design defect, negligence, and failure to warn. The jury ruled in favor of the plaintiffs on each of these claims. Originally, the jury awarded the Pilloids over $55 million in compensatory damages, and $1 billion in punitive damages. That award was reduced to a total of about $81 million.

Monsanto Company (“Monsanto”) – who remain the named plaintiff in the lawsuit despite being purchased by Bayer in 2018 – filed an appeal of the jury verdict in 2020. Among other things, Monsanto argued that the judgment on the plaintiffs’ failure to warn claims should be reversed because the claims are preempted by FIFRA. According to Monsanto, the doctrines of both express and impossibility preemption should have barred the plaintiffs’ claims.

The plaintiffs’ failure to warn claims are based in state common law. This means that the claims do not come from a specific statute, but rather from custom and judicial precedent adopted and enforced by the state of California. Failure to warn is a common law principle of product liability. It is typically raised in lawsuits when a plaintiff’s injuries are the result of a failure to provide adequate warnings associated with the use of a product. In Pilliod v. Monsanto, Co., as with other Roundup lawsuits, the plaintiffs brought failure to warn claims to allege that their injuries were due in part to Monsanto’s failure to provide adequate warnings about the risks of using a product that contains a “probable carcinogen.”

FIFRA is a federal statute that regulates the registration and use of pesticides in the United States. Under FIFRA, a pesticide may not legally be used until the Environmental Protection Agency (“EPA”) registers a label for the product. Pesticide labels are a central component of FIFRA, and once a label is registered it effectively comes law. Therefore, it is a violation of FIFRA to sell or distribute a pesticide which has been “misbranded.” 7 U.S.C. § 136j(a)(1)(F). A pesticide is misbranded if, among other things, “its labeling bears any statement, design, or graphic representation […] that is false or misleading[.]” 7 U.S.C. § 136(q)(1)(A). Additionally, FIFRA prevents states from imposing any labeling or packing requirements that are “in addition to or different from” those required by FIFRA. 7 U.S.C. § 136v(b). Monsanto argues that both FIFRA’s prohibition on misbranded pesticides, and limitation of a state’s ability to add any labeling requirement that is “in addition to or different from” FIFRA labeling requirements preempts any state common law failure to warn claim.

Preemption occurs when a “higher” level of government reduces or eliminates the authority of a “lower” level of government to act on a particular issue. There are different ways that a higher level of government can do this, which means that there are different legal doctrines of preemption. Monsanto argues that the failure to warn claims are preempted under the doctrines of express and impossibility preemption. Typically, express preemption occurs when a law contains either a preemption clause or some other explicit preemptive language. Monsanto argues that the state failure to warn claims are based on common law duties that would ultimately require the state of California to impose labeling requirements warning about the risks of glyphosate. Because such requirements would be “in addition to or different from” the glyphosate labeling requirements imposed by FIFRA, Monsanto believes the failure to warn claims are expressly preempted.

Impossibility preemption occurs when it is legally impossible to comply with both federal and state law. Here, Monsanto argues that the failure to warn claims are subject to impossibility preemption because it would be impossible for Monsanto to add a cancer warning to Roundup under California state law without EPA first altering the federal label.

Appellate Court Ruling

After reviewing the arguments on preemption, the California Court of Appeal issued a decision concluding that the plaintiffs’ failure to warn claims had not been preempted by FIFRA. According to the court, in order to show that the failure to warn claims were preempted, Monsanto had to identify state law requirements that were in addition to or different from the misbranding requirements imposed by FIFRA. The court found that Monsanto was unable to do so.

The court began by explaining that in order to prove failure to warn, the plaintiffs had to show that Monsanto did not warn of a particular risk that was known or that a reasonably prudent manufacturer would have known and warned about. The court when on to acknowledge that while a pesticide may be misbranded if its label contains false or misleading claims, a pesticide may also be misbranded if its labeling “does not contain directions for use which are necessary for effecting the purpose for which the product is intended and it complied with […] are adequate to protect health.” 7 U.S.C. § 136(q)(1)(F). Additionally, a pesticide may be misbranded if its label “does not contain a warning or caution statement which may be necessary and if complied with […] is adequate to protect health.” 7 U.S.C. § 136(q)(1)(G). According to the court, the California common law duty to warn consumers about risks posed by products does not impose any requirements that are different from or in addition to the FIFRA requirement to provide use instructions and warnings that are adequate to protect health. Therefore, the plaintiffs’ failure to warn claims were not expressly preempted by FIFRA.

Next, the court considered whether the failure to warn claims were subject to impossibility preemption, and ultimately determined that they were not. According to the court, Monsanto’s argument of impossibility preemption relied entirely on cases that involved issues of law raised under the Federal Food Drug and Cosmetic Act (“FFDCA”). Monsanto failed to explain why a doctrine of preemption that has been applied to the FFDCA should be applied to FIFRA. Additionally, the court noted that it was unaware of any court opinion in either federal or state court where Monsanto’s theory of impossibility preemption had been applied to FIFRA. Therefore, the court determined that the impossibility preemption did not apply to the plaintiffs’ failure to warn claims.

Because the court found that the failure to warn claims were not preempted, it did not reverse the jury’s ruling.

The Bigger Picture

This is the third court decision from 2021 to analyze Monsanto’s argument that failure to warn claims raised in a glyphosate lawsuit are preempted by FIFRA. The Ninth Circuit Court of Appeals in Hardeman v. Monsanto Co., No. 19-16636 (9th Cir. 2021) found that the claims were not preempted. According to the Ninth Circuit, the common law duty that arose under a failure to warn claim did not impose labeling requirements that were different from or in addition to FIFRA’s prohibition on misbranding. However, a different California State Superior Court found the opposite. The court in Stephens v. Monsanto Co., CIVSB2104801 (Cal. Super. Ct., 2021) concluded that the claims were preempted because requiring a cancer warning that was not part of the federally approved label would be different from or in addition to the labeling requirements imposed by FIFRA.

Additionally, Monsanto has filed an appellate brief in the Eleventh Circuit Court of Appeals making the same preemption arguments in Carson v. Monsanto Co., No. 21-10994 (11th Cir. 2021). As in other Roundup cases, the plaintiff initially filed a variety of state law claims in a lower court, including failure to warn. Monsanto asked the lower court to dismiss the case, and though the court declined to dismiss claims of negligence and design defect, it did dismiss the failure to warn claims on the grounds of preemption. The plaintiff appealed that decision, and the issue of preemption is before the Eleventh Circuit. If the Eleventh Circuit rules in favor of Monsanto, there will be a circuit split on how to interpret the preemption issue, and Monsanto could pursue the claim to the United States Supreme Court. In fact, Monsanto has already expressed its intention to do so. If the preemption issue made it to the Supreme Court, a ruling in Monsanto’s favor could bar failure to warn claims from being brought in future Roundup cases. Such a ruling could potentially prevent failure to warn claims from being raised in lawsuits involving other pesticides as well.

While it is unclear whether there will be a split among the federal circuits, there is now a disagreement between a California State Court of Appeal and a California State Superior Court on whether failure to warn claims are preempted by FIFRA. It is possible that the issue will be appealed to the California Supreme Court, and a ruling could affect both future Roundup cases as well as cases involving other pesticides that are brought in California state courts.


To read the decision in Pilliod v. Monsanto Co., click here.

For more information about preemption under FIFRA, click here.

To read the text of FIFRA, click here.

For additional National Agricultural Law Center information on pesticides, click here.