Chicken feed virus protection claim triggers lawsuit

 Kalmbach Feeds, Inc. v. Purina Animal Nutrition, LLC, 2025 WL 3153412, No. 2:25-cv-00617 (S.D. Ohio Nov. 12, 2025)

One reason I love advertising law is that, eventually, everything lands in it, and I learn about new-to-me corners of the world. Kalmbach sued its competitor Purina for statements about Purina’s poultry feed products under the Lanham Act and the Ohio Deceptive Trade Practices Act, and secured a preliminary injunction on some of its claim.

Kalmbach’s “Henhouse Reserve” is aimed at the “backyard” poultry market, as is Purina’s “Farm to Flock.” They are both granola-like “premium” feeds aimed at owners who keep egg-laying hens. “Backyard chicken flock owners tend to have fewer chickens; they may treat their chickens more like pets and pay for premium feed. … Backyard owners may also be more emotionally motivated to keep their chickens alive, because they might keep their chickens as a hobby, for eco-conscious reasons, or because they view them as their pets. Thus, they may be particularly concerned about recent avian influenza outbreaks.”

Farm to Flock contains “FeedLock,” a “multispecies feed additive technology” consisting of medium-chain fatty acids which are designed to interact with the membranes of envelope viruses and “deactivate” them. “Although medium-chain fatty acids have been found to help prevent outbreaks of disease in swine, to date, there is no evidence that they impact disease outbreaks in poultry.”

Nonetheless, for a month and a half in 2025, Purina actively marketed Farm to Flock as “helping to defend against bird flu.” It based this claim on (1) a lab test and (2) an assumption. For (1), Purina and its codeveloper dosed four samples of chicken feed with varying levels of FeedLock and H5N1, and one sample of control feed with H5N1 only. The FeedLock feed “showed reduced viral loads” after twelve hours, while the control sample showed stable levels of bird flu for a week. For (2), based on the “consensus in the swine industry,” stemming from a commercial swine study, that medium-chain fatty acids “inhibited the transmission of [swine envelope virus] pathogens in the feed to” swine, Purina extrapolated that the medium-chain fatty acids in FeedLock would similarly inhibit the transmission of the avian influenza envelope virus pathogens to poultry.

Purina directly advertised its Farm to Flock bird flu defense claims on its website and social media platforms, as well as through direct communications to consumers and distributors across the United States. Its employees, including scientists and sales representatives, repeated variations of these claims on webinars and at in-person industry meetings. In describing the purported flu-fighting properties of Farm to Flock, Purina’s employees sometimes claimed it “has been shown to be protective against, protecting against viruses...includ[ing] bird flu.”

one example of the virus defense claims; more below

Regulators in Kansas and Minnesota quickly raised concerns, to which Purina responded by removing its claims and requesting that similar claims made by third parties be taken down. The FDA subsequently identified an additional statement that Purina needed to edit or remove, which it did. But Kalmbach, believing it had already suffered damage, brought suit.

The court considered the state and federal claims to have identical standards.

Purina argued that claims like “helps defend against bird flu” referred to defending the feed from becoming a transmission mechanism for bird flu, not to defending the birds against bird flu. The court didn’t find that a plausible reading. Anyway, such claims were “scientifically dubious,” given that chicken feed was not known to be a transmission vehicle in the first place; swine feed can be a source of transmission for viruses in swine, but those swine viruses don’t affect birds. Its lab test didn’t show a decreased risk of chickens contracting bird flu. Thus, the court found that the statements about the impact of FeedLock feed on avian influenza were likely to be found literally false.

Purina’s “immunity” statements were also literally false. Not only did Purina tout its feed’s “Complete...Defense for Laying Hens” and “Fun-filled, flu-fighting goodness” in large font at the top of the advertisement, with the supposed caveat explaining that this defense relates to the feed in small font at the bottom, even the caveat was false: “FeedLock® is a breakthrough ingredient of the system that nourishes and protects, helping to instantly defend your flock against avian influenza, while also boosting immunity and breaking down harmful pathogens on the feed with every bite.” This reference to “immunity” indicated that Purina was making claims both about FeedLock’s interaction with avian influenza on feed, where FeedLock supposedly would break down pathogens, and about avian influenza in a bird, where FeedLock would supposedly boost immunity. Purina’s own expert witness testified that it was “improper” to represent that FeedLock provides any “immunity or treatment against avian influenza.”

ad claiming to support "immune, digestive & overall health"

And, given the expert consensus that feed is not recognized as a “transmission vector of bird flu,” Purina’s “more ambitious” statements that FeedLock defends against the bird flu, apart from any immunogenic function, were also literally false. “If feed is not a known transmission vector—and Purina’s laboratory test does not show that it is—protecting the feed could have no impact on whether birds would get avian influenza.” At most, Purina’s expert would only say that “[FeedLock] would definitely be able to interact with that virus and break down the viral envelope,” which would then reduce the infectivity of the virus to some extent—but she would not say that it could “neutralize” the virus. Even in the lab, infected feed was only “approaching nondetectable or approaching noninfective” once treated with FeedLock (emphasis added). “Purina had no evidence showing Purina feed infected with avian influenza, once treated with FeedLock, ever had a nondetectable or noninfective amount of avian influenza.” And the feed tested in the lab was poultry mash feed— “a ground feed different than Farm to Flock.” [Some parts of this sound like “lack of substantiation” arguments, something that shows up later in the remedy discussion, though taken together they plausibly add up to literal falsity. In addition, given the scientific nature of the claims, it is reasonable to treat them as “tests prove” claims, which means that they can be falsified by showing that the tests don’t prove the ad claim.]

social media post

In addition, Purina necessarily implied false statements about “defense against” bird flu.  E.g., claims that FeedLock “helps defend your flock....It helps to support strong healthy hens by actively supporting and fortifying immunity and gut health” had to be read in context with Purina’s claim in that same ad that “FeedLock®...helps defend your flock against avian influenza and other viruses” and claims that the feed “give[s] your hens the wellness boost they deserve with layer feed that nourishes AND defends: [f]ortifies immunity and helps defend against bird flu[,] [g]ut health support[,] [s]trong shells, vibrant yolks.” These claims necessarily implied that the feed would defend the chicken against bird flu after consumption, and that the feed gives the hens a wellness boost.

“Every other claim in the ad (that the feed nourishes, fortifies immunity, supports gut health, leads to stronger shells and vibrant yolks) suggests a benefit to the hen, not the feed.” Thus, even assuming the bird flu defense claim could technically/linguistically be about the feed, it was false by necessary implication. “Purina cannot be heard to claim that this one statement, buried among six about how Purina feed benefits the health of hens, is about a benefit to the feed itself. It cannot be heard to say that any claim that its feed fortifies immunity is unrelated to a claim that the feed defends against viruses.” Purina’s proposed truthful meaning was not reasonable and thus the claim could not be called ambiguous.  The court noted that other ads suggest that the more FeedLock feed a bird consumes, the stronger its immunity becomes: “FeedLock®...help[s] to instantly defend your flock against avian influenza, while also boosting immunity...with every bite.”

“[S]ome of these ads plainly and facially imply that FeedLock feed is defending or mitigating avian influenza in the chickens themselves by ‘boosting immunity.’” Letters and inquiries from Purina’s regulators confirm this implication.” (Among other things, the FDA took issue with advertising statements about the bird flu that lacked “explicit reference to the feed itself.”)

another ad

The ads also necessarily implied that FeedLock defended backyard chickens more when more feed is consumed, and continued to defend chickens even after consumption—by offering continuing immunogenic and health benefits to the birds “with every bite.” The combination of immunity and health claims along with claims that FeedLock feed “defends against” avian influenza and other viruses “necessarily implies that FeedLock is providing some antiviral value to the bird itself, including after consumption. Based on the record, this appears to be false.”

So too with the necessary implication of statements claiming benefits against “other viruses.” “Viruses,” plural, “necessarily and unambiguously implies, in the context of an advertisement for ‘Hen Food,’ that there are other viruses that FeedLock defends against.” Again, the record supported falsity. “Avian influenza is the only virus known to infect birds.”

fact sheet (or is it?) claiming to fight "viruses like" bird flu

The court didn’t bother with misleadingness (though some evidence shows up in the materiality discussion), because literal falsity can be presumed deceptive. There was direct and indirect evidence of materiality: direct from customer inquiries, which can show that a claim was purchase-relevant, and indirect. “One of Kalmbach’s sales representatives testified that she was told by customers and potential customers that they wouldn’t consider Kalmbach’s Henhouse Reserve feed because it lacked a bird flu preventative or bird flu prevention, unlike Purina’s Farm to Flock.” (Not hearsay because not offered for the truth of the matter asserted.) Plus, Kalmbach showed that Purina “misrepresented an inherent quality or characteristic of the product.” Advertising virus defense is likely to induce consumers to believe they are getting a better product than feed that does not offer such a defense. Purina’s own internal consumer research results concluded that such claims were “most motivating” to customers; Kalmbach’s expert testified that many consumers in this market “are more emotionally motivated to keep their chickens alive, and are concerned by recent outbreaks of avian influenza,” and Purina’s expert agreed that backyard owners “are emotionally connected to their flock.” Purina’s senior marketing manager testified that Purina’s consumers “started to humanize or personify their chickens, and so they treated them like family. They were more like pets like cats and dogs.” [I hate to ask, but, based on this story, I have to wonder: is MAGA going to go after antivirals in chicken feed? Will they worry about chicken autism?]

another example

The court pointed specifically to a Purina internal report finding that the vast majority of consumers in the market found “brands that spend time educating customers are more trustworthy,” [of relevance far beyond this case!] and thought it was “important to stay up to date on the latest nutrition for animals.” It did not follow that consumers would be skeptical of such claims: “If anything, it seems logical that consumers would be less inclined to scrutinize Purina’s claims because they would trust Purina, believing that Purina’s efforts to educate consumers as to their feed’s purported benefits were based on the latest updates in animal nutrition.” And Kalmbach’s sales rep supported this by testifying that she told a potential customer that the claim wasn’t true, and received the question: why would Purina advertise it if it wasn’t true?

Causation/harm: “[T]o obtain injunctive relief[,] logical likelihood of damages is sufficient.” Given the presumption of deception and the existence of some evidence of misleadingness, including a consumer inquiry into why Kalmbach does not “have a product like [Purina’s] that can defend against bird flu,” Kalmbach was a likely victim of Purina’s acts.

There was a presumption of irreparable injury. Purina argued that the presumption was rebutted here because any lost sales could be recouped by money damages, and there was no evidence supporting “a more severe and ongoing injury,” like a dealer dropping Kalmbach for Purina or reputational damage. It also argued that requiring it to contact its customers would be too extreme here, where there is no ongoing, irreparable injury.

Characterizing the issue as one of “presumption of harm,” rather than presumption of irreparable injury, the court found that there was still the distinct possibility that Kalmbach will suffer injury, which is the wrong question, but the right one probably still has the same answer. That’s because,

although Purina sent out three blast emails to 130,000 recipients about Farm to Flock with statements regarding avian influenza, it has never corrected those emails. Should any of those 130,000 email recipients (or any further recipients of those emails) rely on those emails, further disseminate those emails, or refer back to those emails today or in the future, they may believe Purina still represents that its Farm to Flock feed helps defend against bird flu. Because it would be difficult, if not impossible, to calculate whether Purina’s more recent sales of Farm to Flock were a result of these latent advertisements, calculating damages would be futile.

Purina argued that Kalmbach’s supposed delay in bringing the motion undermined any claim of irreparable harm. Kalmbach learned about Purina’s advertisements in April and sued in early June; that wasn’t a sufficient delay to undermine Kalmbach’s claim of irreparable injury, especially given that Kalmbach would need some time to evaluate the scientific claims.

Harm to Purina/balance of equities: Purina stopped further publication but didn’t issue corrective statements. Purina argued that a public retraction would risk damaging its reputation. At the preliminary injunction stage, a court order proclaiming its ads were “unsupported and untrue” would erode brand trust and goodwill, so that would be inappropriate. To be sure, this was something of “a self-imposed risk” to Purina, so the court tailored the injunction to avoid some of Kalmbach’s proposed harshness.

Purina initially consented to a mostly prohibitory preliminary injunction: stop the accused advertising and notify distributors, retailers, and marketing affiliates to cease use and dissemination of that advertising. Kalmbach wanted Purina to publish a statement saying its claims were untrue and that it was retracting them.

“Purina’s argument is mainly that requiring any public statement on Purina’s part would be too extreme, and Purina points to cases where courts ordered much more tailored relief.” The lesson was that “retractions should be issued in instances where identifiable third parties received the challenged claim,” and here those were emails. “Just because Purina has addressed some forms of its prior advertisements does not mean that all confusion will have dissipated. Thus, Purina must issue some form of a retraction.”

But the court would limit the language. The antivirus claim was false “for the purposes of the Lanham Act and the Ohio Deceptive Trade Practices Act because Purina had no empirical support or basis for it, and the scientific consensus today suggests that it is incorrect.” But Kalmbach’s expert testified that it is possible that avian influenza could live on chicken feed, and that if a bird ingested that infected feed, that bird could get avian influenza. And it was an open question whether FeedLock would have any effect on avian influenza in bird feed, or the population of birds that eat that feed. [It’s possible that sprinkling a mix of cinnamon and cumin into the feed would protect birds; this is why the Third Circuit held that making unsubstantiated claims that you have no reason to think are true counts as making literally false claims. It’s bullshit in the sense that you have no interest in the truth value of your claim; you’re just making it to sell the product. And that’s not an attitude towards truth worth protecting even if “lack of substantiation” claims are otherwise unavailable.]

But, anyway, this was a preliminary injunction and not a final determination of falsity, so the court required the retraction (to be sent to email recipients and posted on Purina’s website) to say “At the preliminary injunction stage, the Court found that Purina engaged in false advertising because these statements were not scientifically grounded and lacked a scientific basis. Purina retracts these statements, as well as any other representation that Purina’s Farm to Flock 18% Layer Hen Food defends against, protects against, prevents, mitigates, or provides immunity to the effects of avian influenza, bird flu, or other viruses.” [Quick TOS question: does your TOS warn people who unsubscribe from your mailing list that you might have to contact them in the future for legal compliance?] [Quick reading comprehension question: what percentage of consumers will consider the reputational hit to Purina decreased because it’s just a preliminary injunction? I think the court did the right thing, but that doing so will not change the effects on Purina’s overall reputation one jot. Which is to say that sometimes we should be happily normative about these issues.]

Note: the court specified URLs at which the notice should be given, and they’re not there yet, but Purina has 10 days, which (as of Nov. 14) have not yet passed.