Supreme Court Vacates $28 Million Roundup Verdict in Dennis v. Monsanto, Sends It Back Under Durnell

The Supreme Court sent the $28 million Roundup verdict back on October 13

The Supreme Court on Tuesday, October 13, 2026, granted Monsanto's petition for certiorari in Dennis v. Monsanto, vacated the $28 million Roundup verdict won by Carlsbad, California resident Mike Dennis, and remanded the case to the California Court of Appeal for further consideration in light of its June decision in Monsanto Co. v. Durnell. The order does not itself enter judgment for Monsanto, but the $28 million Roundup verdict now rests entirely on a Failure to Warn theory that Durnell held preempted, because the San Diego jury rejected Dennis's Design Defect and negligence claims in 2023.

That second sentence is the part of today's order that most coverage has skipped, and it is the part that decides what happens next. Several Roundup plaintiffs have kept their cases alive since June by arguing that Durnell reached only label-based warning claims and left design and negligence theories intact. Dennis cannot make that argument with the same force. His jury already heard those theories and found for Monsanto on them. What remains on remand is a judgment built on exactly the kind of claim the Supreme Court said state law cannot impose.

The order is a one-line disposition on the Court's Tuesday order list. It is the latest in a series of Roundup cases the Court has returned to state appellate courts since Durnell, and it puts a California warning verdict, with a punitive award attached, squarely in front of a state court that must now apply the new rule.

What did the Supreme Court do with the $28 million Roundup verdict?

The Supreme Court granted Monsanto's petition, vacated the California Court of Appeal's judgment affirming the $28 million Roundup verdict, and remanded the case for that court to reconsider it in light of Monsanto Co. v. Durnell, No. 24-1068. Lawyers call this disposition a GVR: grant, vacate, and remand.

A GVR is narrower than the headlines suggest. Courthouse News described the Court as having "tossed" the $28 million ruling; Mealey's and Law360 described the same order, more precisely, as a grant, vacatur, and remand. The distinction matters for anyone tracking the case:

• What a GVR does. It wipes out the appellate judgment under review, so the November 2025 affirmance no longer stands. The case returns to the same California appellate panel's docket as an open appeal.
• What a GVR does not do. It is not a ruling on the merits of Dennis's case. The Supreme Court did not hold that his specific claims are preempted, did not reinstate or reduce any damages, and did not decide the punitive damages question Monsanto also raised.
• The governing standard. Under Lawrence v. Chater, 516 U.S. 163 (1996), the Court issues a GVR when an intervening decision creates a reasonable probability that the lower court would reach a different result if given the chance to apply it. That is a judgment about likelihood, not a reversal.

So Dennis has not "lost" in the Supreme Court in a formal sense. The Court has instead told the California Court of Appeal to apply Durnell to a record that, as explained below, leaves very little room for a different answer.

Did the Supreme Court overturn the Dennis v. Monsanto verdict?

Not directly. The Supreme Court vacated the California appellate judgment that upheld the verdict and sent the case back for reconsideration; the trial court's $28 million judgment will stand or fall depending on what the California Court of Appeal does on remand. Monsanto has said it will ask that court to vacate the verdict outright.

A Monsanto spokesperson told Courthouse News: "We are pleased with the court's decision and will urge the California appellate court to vacate the verdict in this case."

Dennis did not fight the disposition. Mealey's reported in September that Dennis informed the Court that he "does not oppose the disposition the petition requests," meaning he accepted a remand rather than asking the justices to deny review outright. That is a common choice for a respondent facing an intervening adverse decision: a remand at least preserves the chance to argue in the state appellate court that Durnell does not reach the particular record, while full plenary review would risk a binding Supreme Court ruling on that record.

How much did the jury award Mike Dennis against Monsanto?

A San Diego County Superior Court jury awarded Mike Dennis $332 million on October 31, 2023: $7 million in compensatory damages and $325 million in Punitive Damages. Judge Kevin Enright later reduced the punitive award to $21 million, producing the $28 million judgment that the California Court of Appeal affirmed and the Supreme Court has now vacated.

Dennis, who was 57 at the time of trial, sued Monsanto in San Diego Superior Court in 2021, asserting product liability and fraud claims. He was diagnosed in 2020 with mycosis fungoides, a rare form of non-Hodgkin lymphoma that primarily affects the skin, and attributed it to decades of spraying Roundup on his property. His trial team argued that glyphosate, Roundup's active ingredient, is genotoxic and damages DNA after it is absorbed through the skin.

The verdict was split in a way that now matters a great deal. According to the Associated Press account of the verdict, the jury concluded that Monsanto failed to warn consumers about Roundup's risks, but sided with Monsanto in finding that the product's design was not defective and that the company was not negligent. The punitive award followed from the warning finding.

The $28 million Roundup verdict, step by step

Date	Court	Event	Amount
2021	San Diego County Superior Court	Dennis files product liability and fraud suit	—
Oct. 31, 2023	San Diego County Superior Court	Jury finds failure to warn; rejects design defect and negligence	$7M compensatory + $325M punitive = $332M
Feb. 26, 2024	San Diego County Superior Court (Judge Kevin Enright)	New trial denied; JNOV granted in part; punitive damages cut as unconstitutionally excessive	$7M + $21M = $28M
Nov. 24, 2025	Cal. Court of Appeal, 4th Dist., Div. 1 (No. D084130)	Judgment affirmed; FIFRA preemption and due process arguments rejected	$28M affirmed
May 2026	U.S. Supreme Court (No. 25A1284)	Monsanto seeks extension to file cert petition while Durnell is pending	—
June 25, 2026	U.S. Supreme Court	Monsanto Co. v. Durnell decided 7-2 for Monsanto	—
Oct. 13, 2026	U.S. Supreme Court	Petition granted, judgment vacated, case remanded in light of Durnell	$28M judgment in jeopardy

The February 2024 reduction was itself significant. Bayer described it as a cut of more than 90 percent and said it was consistent with reductions in the first three Roundup trials. Judge Enright found that the $325 million punitive award bore no reasonable relationship to the $7 million in compensatory damages and exceeded constitutional limits, leaving punitive damages at three times the compensatory award. Bayer nonetheless objected that the liability finding was left in place, and Monsanto appealed both liability and the reduced punitive award.

Why did the Supreme Court send the Dennis Roundup case back?

The Supreme Court sent the Dennis case back because the California Court of Appeal affirmed the $28 million Roundup verdict on a FIFRA preemption theory that Durnell rejected. The appellate panel held that the Federal Insecticide, Fungicide, and Rodenticide Act does not preempt state failure-to-warn claims that parallel federal misbranding requirements; seven months later, the Supreme Court held that a warning claim requiring a cancer warning on an EPA-approved label is expressly preempted.

What the California Court of Appeal held in November 2025

In its November 24, 2025 opinion in Dennis v. Monsanto Co., No. D084130, the Fourth Appellate District, Division One, rejected each of Monsanto's main arguments:

1. Preemption. Following Bates v. Dow Agrosciences LLC, 544 U.S. 431 (2005), and earlier California Roundup decisions, the panel held that FIFRA does not preempt state-law warning claims that parallel FIFRA's own prohibition on misbranding. That "parallel requirements" reasoning was the foundation on which the plaintiffs' bar had built every warning-based Roundup verdict since 2018.
2. Punitive damages. The panel held that the reduced $21 million punitive award did not violate due process because it rested on highly reprehensible conduct directly related to Dennis's harm. Monsanto had argued that it was being punished repeatedly, across multiple Roundup verdicts, for the same course of conduct, and that the ratio was excessive.

Monsanto then sought more time from the Supreme Court to file its petition, telling the Court in its extension application (No. 25A1284) that the preemption question was already pending in Durnell. The application also flagged a second question: the due process limits on duplicative punitive damages awards imposed for the same conduct in serial mass tort trials.

What Durnell decided

Monsanto Co. v. Durnell, decided June 25, 2026, arose from a Missouri jury verdict for John Durnell. The Court granted review on January 16, 2026, heard argument on April 27, 2026, and ruled 7-2 for Monsanto. Justice Kavanaugh wrote for the Court; Justice Thomas concurred; Justice Jackson dissented, joined by Justice Gorsuch.

The holding is direct: 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." The statutory hook is 7 U.S.C. § 136v(b), which bars states from imposing labeling or packaging requirements "in addition to or different from" those required under FIFRA. The majority treated EPA's approval of a Roundup label without a cancer warning as the federal requirement that a state jury verdict cannot contradict.

What Durnell did not decide is equally important. It did not address whether glyphosate causes cancer. It did not hold that Design Defect, negligence, or testing claims are preempted. It did not resolve whether warning theories untethered to the label, such as advertising or point-of-sale statements, survive. Lower courts have been sorting those questions since June, and that sorting is exactly what the California Court of Appeal must now do for the Dennis record.

Why the Dennis record is weaker than other post-Durnell Roundup cases

The Dennis jury's split verdict makes this remand harder for the plaintiff than most. Courts that have kept Roundup cases alive since Durnell have done so by separating label-based warning claims from everything else, and Dennis has very little "everything else" left.

Consider how the other post-Durnell cases have come out:

• Merril Hoge (District of Idaho). On October 7, 2026, U.S. District Judge David Nye refused to dismiss the former NFL running back's case in full. He barred a "label-adjacent" warning theory but let Hoge's negligence claim proceed because it was "not wholesale pre-empted."
• Boone County, Missouri. On August 31, 2026, Circuit Judge Jeff Harris denied Monsanto summary judgment, confining Durnell to warning claims and rejecting implied preemption of design defect and negligence claims.
• Aretino v. Monsanto (St. Louis County). The first post-Durnell Roundup trial opened September 29, 2026, before Judge Brian May, with three plaintiffs trying only design defect and inadequate-testing theories. Testimony was continuing in early October with no verdict reported.

Each of those cases survives because the plaintiff still has a non-warning claim to try. Dennis tried his non-warning claims and lost them. A California appellate court applying Durnell therefore faces a much simpler question: does a verdict resting only on failure to warn, with punitive damages derived from that finding, survive a holding that FIFRA preempts warning claims requiring a different label?

The answer turns on how the warning claim was tried. If Dennis's warning theory was, as Courthouse News and the original trial coverage describe it, that Monsanto should have warned of Roundup's cancer risk, then it is the same claim Durnell addressed. Dennis's best remaining argument is that some part of the warning case rested on communications other than the EPA-approved label, a distinction Judge Nye in Idaho viewed skeptically when he labeled such theories "label-adjacent."

What happens next in Dennis v. Monsanto?

The case now returns to the California Court of Appeal, Fourth Appellate District, Division One, which will likely order supplemental briefing on how Durnell applies before deciding whether to reverse the $28 million judgment, order a new trial on any surviving theory, or, less likely, affirm on a ground Durnell does not reach. Monsanto has said it will ask the court to vacate the verdict.

The realistic pathways on remand are:

Outcome on remand	What it requires	Practical effect
Reversal with directions to enter judgment for Monsanto	Panel finds the only liability theory tried is preempted and no non-label theory supports the verdict	Dennis recovers nothing; punitive damages issue moot
Reversal and remand for a new trial	Panel finds some warning evidence was not label-based, or that a retrial on a properly limited theory is warranted	Case returns to San Diego Superior Court; prior design and negligence findings likely bind
Affirmance on an alternative ground	Panel finds Monsanto forfeited or failed to preserve a preemption argument of the Durnell type, or that the claim did not require a label change	$28M judgment reinstated; Monsanto likely seeks review again
Punitive damages revisited	Only if liability survives	The "duplicative punishment" due process question returns

Three practical points shape the timing and stakes.

The interest clock. California judgments ordinarily accrue post-judgment interest at 10 percent a year under Code of Civil Procedure § 685.010. On a $28 million judgment entered in early 2024, the accrued interest is a material sum, and it would be lost along with the principal if the judgment is reversed.

Preservation. Monsanto pressed FIFRA preemption on appeal and the Court of Appeal decided the issue on the merits, which makes a forfeiture argument difficult for Dennis.

Timing. California appellate courts typically allow the parties to file supplemental letter briefs after a GVR. A decision in 2027 is the likeliest outcome, though the court could move faster given that the legal question has narrowed.

Which other Roundup verdicts has the Supreme Court sent back?

Dennis is the fourth Roundup case the Supreme Court has returned to a state appellate court since Durnell. On June 30, 2026, five days after deciding Durnell, the Court granted, vacated, and remanded three Roundup cases, including Monsanto Co. v. Johnson (No. 24-1098) to the Court of Appeals of Oregon and Monsanto Co. v. Anderson (No. 25-1042) to the Missouri Court of Appeals, Western District.

Anderson is the largest. It is the Cole County, Missouri case in which a November 2023 jury awarded about $1.56 billion to three plaintiffs, Daniel Anderson, Jimmy Draeger, and Valorie Gunther; Circuit Judge Daniel Green reduced the punitive awards, and the Western District affirmed a $611 million judgment on May 27, 2025, rejecting Monsanto's FIFRA preemption argument.

Post-Durnell scorecard for Roundup verdicts and claims

Case	Forum	Award at issue	Post-Durnell status
Durnell	Missouri (City of St. Louis)	$1.25M (2023 verdict)	Reversed by Supreme Court, June 25, 2026
Anderson (Anderson, Draeger, Gunther)	Mo. Ct. App., W.D. (Cole County)	$611M judgment	GVR June 30, 2026; on remand
Johnson (Larry)	Oregon Court of Appeals	Not verified	GVR June 30, 2026; on remand
Dennis	Cal. Ct. App., 4th Dist., Div. 1 (San Diego)	$28M judgment	GVR Oct. 13, 2026; on remand
Hoge	D. Idaho	No verdict	Warning claim barred; negligence survives (Oct. 7, 2026)
Aretino	St. Louis County Circuit Court	No verdict	Design defect trial underway since Sept. 29, 2026

The pattern is consistent: warning-based judgments are being sent back, while pending cases that plead design or negligence theories are being allowed to proceed. Earlier California warning verdicts are largely beyond reach. Dewayne Johnson's 2018 verdict was cut to about $20.5 million and became final after the California Supreme Court declined review, and the Supreme Court denied Monsanto's petition in the federal Hardeman case in 2022. Durnell does not reopen judgments that are already final.

Can Roundup plaintiffs still sue after Monsanto v. Durnell?

Yes, but not on the theory that Monsanto should have put a cancer warning on Roundup's label. After Durnell, a Roundup plaintiff must plead and prove a claim that does not require a label different from the one EPA approved, such as Design Defect, negligent design or testing, or, in some courts, negligence based on conduct other than labeling.

The Dennis remand sharpens what that means for case selection. A plaintiff whose complaint, discovery, and expert work were built around the missing warning is in a far weaker position than one who developed a design or testing theory from the outset. General Causation remains contested in every forum, and Durnell did not change the science; what it changed is which legal vehicle can carry that causation evidence to a jury.

For claims still in the federal Multidistrict Litigation (MDL), In re: Roundup Products Liability Litigation, MDL 2741, before Judge Vince Chhabria in the Northern District of California, Monsanto has moved to dismiss remaining cases under Durnell; roughly 3,925 actions were pending there as of September 1, 2026, according to trackers citing JPML data. The Dennis remand does not bind Judge Chhabria, but a California appellate ruling that a warning-only verdict cannot survive would reinforce Monsanto's position that repackaged warning claims must be dismissed.

Does the Dennis ruling affect the $7.25 billion Roundup settlement?

Not directly, but it strengthens the case for approval of the $7.25 billion Roundup class settlement and lowers the value of opting out. The settlement, King v. Monsanto, is before Judge Timothy Boyer of the Circuit Court of the City of St. Louis, who held a final fairness hearing on September 14, 2026 and had not issued a ruling in reports through early October.

The settlement would resolve roughly 65,000 pending claims and a nationwide futures subclass through declining, capped annual payments over as long as 21 years, with individual awards running from roughly $10,000 to $165,000 across a Settlement Matrix of nine tiers. Objectors have argued that the grid undervalues claims and that class counsel's $675 million fee request is excessive.

The Dennis order bears on that fight in two ways. First, it reinforces the risk side of the objectors' calculus: a claimant who opts out to pursue a warning theory now faces not only a trial but the near-certainty that any resulting verdict will be challenged under Durnell. Second, it removes one more large judgment that objectors could cite as evidence of what Roundup claims are worth at trial. Each vacated verdict makes the settlement's tiered values look more like a premium over litigation risk than a discount.

What it means for plaintiffs' counsel, defendants, and funders

The analysis below is general commentary, not legal advice.

For plaintiffs' counsel with Roundup inventories. Review every pending case for the theories actually pleaded and developed. Cases that rest on failure to warn alone should be evaluated against the settlement grid, not against pre-2026 verdicts. Cases with developed design and testing theories, especially those that can avoid label-adjacent framing, carry real value after Hoge and the Boone County ruling, and Aretino will provide the first jury data point. Trial verdict forms matter: the Dennis split verdict shows how a defense win on design defect years ago can decide a case after the law changes.

For defendants in other pesticide and FIFRA-regulated product cases. Durnell plus serial GVRs give manufacturers of EPA-registered pesticides a strong express preemption defense to label-based warning claims, including in other pesticide litigation where warning theories feature. The remaining exposure is in design, testing, and negligence theories, so defense strategy will shift toward attacking those as warning claims in disguise.

For appellate practitioners. The Dennis record illustrates why preservation and special verdict forms matter in a Mass Tort. Monsanto's preemption objection, pressed and decided below, survived seven years of adverse precedent until the Supreme Court took it up. The punitive damages question Monsanto also raised, whether serial punitive awards for the same course of conduct violate due process, remains open and may resurface in a case where liability survives.

For litigation funders and lien holders. Any financing secured against warning-based Roundup judgments on appeal should be marked down. Medical Lien holders and plan administrators with interests in vacated or soon-to-be-vacated judgments should expect recovery, if any, to come through the settlement program rather than from trial awards.

FAQ

What did the Supreme Court do with the $28 million Roundup verdict?

On October 13, 2026, the Supreme Court granted Monsanto's petition, vacated the California Court of Appeal's judgment affirming the $28 million Roundup verdict for Mike Dennis, and remanded the case for reconsideration in light of Monsanto Co. v. Durnell.

Why did the Supreme Court send the Dennis Roundup case back?

Because the California Court of Appeal had held that FIFRA does not preempt Roundup failure-to-warn claims, and the Supreme Court held the opposite in Durnell on June 25, 2026, ruling 7-2 that a state claim requiring a cancer warning on Roundup's EPA-approved label is expressly preempted.

How much did the jury award Mike Dennis against Monsanto?

The San Diego County jury awarded $332 million on October 31, 2023: $7 million in compensatory damages and $325 million in punitive damages. The trial judge reduced the punitive award to $21 million in February 2024, leaving a $28 million judgment.

What happens next in Dennis v. Monsanto?

The California Court of Appeal, Fourth Appellate District, Division One, will reconsider the appeal under Durnell. Because the jury rejected Dennis's design defect and negligence claims and found only failure to warn, Monsanto will argue that the judgment must be reversed outright; Dennis will need to show that some part of his warning claim did not depend on the label.

Which other Roundup verdicts has the Supreme Court sent back?

On June 30, 2026, the Court sent back three Roundup cases in light of Durnell, including Monsanto Co. v. Anderson, the $611 million Cole County, Missouri judgment, and Monsanto Co. v. Johnson from the Oregon Court of Appeals. Dennis, on October 13, is the fourth.

Does the Dennis ruling affect the $7.25 billion Roundup settlement?

It does not change the settlement's terms, but it makes opting out to pursue a warning claim less attractive and supports the argument that the settlement's $10,000 to $165,000 award range reflects real litigation risk. Judge Timothy Boyer's ruling on final approval remained pending in early October 2026.