Chicken feed virus protection claim triggers lawsuit

 Kalmbach Feeds, Inc. v. Purina Animal Nutrition, LLC, 2025WL 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. Kalmbachsued its competitor Purina for statements about Purina’s poultry feed productsunder the Lanham Act and the Ohio Deceptive Trade Practices Act, and secured apreliminary 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 chickenflock owners tend to have fewer chickens; they may treat their chickens morelike pets and pay for premium feed. … Backyard owners may also be moreemotionally motivated to keep their chickens alive, because they might keeptheir chickens as a hobby, for eco-conscious reasons, or because they view themas their pets. Thus, they may be particularly concerned about recent avianinfluenza outbreaks.”

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

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

Purina directly advertised its Farmto Flock bird flu defense claims on its website and social media platforms, aswell as through direct communications to consumers and distributors across theUnited States. Its employees, including scientists and sales representatives,repeated variations of these claims on webinars and at in-person industrymeetings. In describing the purported flu-fighting properties of Farm to Flock,Purina’s employees sometimes claimed it “has been shown to be protectiveagainst, 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 claimsmade by third parties be taken down. The FDA subsequently identified anadditional 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 haveidentical standards.

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

Purina’s “immunity” statements were also literally false. Notonly did Purina tout its feed’s “Complete...Defense for Laying Hens” and“Fun-filled, flu-fighting goodness” in large font at the top of theadvertisement, with the supposed caveat explaining that this defense relates tothe feed in small font at the bottom, even the caveat was false: “FeedLock® isa breakthrough ingredient of the system that nourishes and protects, helping toinstantly defend your flock against avian influenza, while also boostingimmunity and breaking down harmful pathogens on the feed with every bite.” Thisreference to “immunity” indicated that Purina was making claims both about FeedLock’sinteraction with avian influenza on feed, where FeedLock supposedly would breakdown pathogens, and about avian influenza in a bird, where FeedLock wouldsupposedly boost immunity. Purina’s own expert witness testified that it was“improper” to represent that FeedLock provides any “immunity or treatmentagainst avian influenza.”

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

And, given the expert consensus that feed is not recognizedas a “transmission vector of bird flu,” Purina’s “more ambitious” statementsthat FeedLock defends against the bird flu, apart from any immunogenic function,were also literally false. “If feed is not a known transmission vector—andPurina’s laboratory test does not show that it is—protecting the feed couldhave no impact on whether birds would get avian influenza.” At most, Purina’sexpert would only say that “[FeedLock] would definitely be able to interactwith that virus and break down the viral envelope,” which would then reduce theinfectivity 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 “approachingnondetectable or approaching noninfective” once treated with FeedLock(emphasis added). “Purina had no evidence showing Purina feed infected withavian influenza, once treated with FeedLock, ever had a nondetectable ornoninfective amount of avian influenza.” And the feed tested in the lab was poultrymash feed— “a ground feed different than Farm to Flock.” [Some parts of thissound like “lack of substantiation” arguments, something that shows up later inthe remedy discussion, though taken together they plausibly add up to literalfalsity. In addition, given the scientific nature of the claims, it is reasonableto treat them as “tests prove” claims, which means that they can be falsifiedby showing that the tests don’t prove the ad claim.]

social media post

In addition, Purina necessarily implied false statementsabout “defense against” bird flu.  E.g.,claims that FeedLock “helps defend your flock....It helps to support stronghealthy hens by actively supporting and fortifying immunity and gut health” hadto 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 deservewith layer feed that nourishes AND defends: [f]ortifies immunity and helpsdefend against bird flu[,] [g]ut health support[,] [s]trong shells, vibrantyolks.” These claims necessarily implied that the feed would defend the chickenagainst bird flu after consumption, and that the feed gives the hens a wellnessboost.

“Every other claim in the ad (that the feed nourishes,fortifies immunity, supports gut health, leads to stronger shells and vibrantyolks) suggests a benefit to the hen, not the feed.” Thus, even assuming thebird flu defense claim could technically/linguistically be about the feed, itwas false by necessary implication. “Purina cannot be heard to claim that thisone statement, buried among six about how Purina feed benefits the health ofhens, is about a benefit to the feed itself. It cannot be heard to say that anyclaim that its feed fortifies immunity is unrelated to a claim that the feeddefends against viruses.” Purina’s proposed truthful meaning was not reasonableand thus the claim could not be called ambiguous.  The court noted that other ads suggest thatthe 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 thatFeedLock feed is defending or mitigating avian influenza in the chickensthemselves by ‘boosting immunity.’” Letters and inquiries from Purina’sregulators confirm this implication.” (Among other things, the FDA took issuewith advertising statements about the bird flu that lacked “explicit referenceto the feed itself.”)

another ad

The ads also necessarily implied that FeedLock defendedbackyard chickens more when more feed is consumed, and continued to defendchickens even after consumption—by offering continuing immunogenic and healthbenefits to the birds “with every bite.” The combination of immunity and healthclaims along with claims that FeedLock feed “defends against” avian influenzaand other viruses “necessarily implies that FeedLock is providing someantiviral value to the bird itself, including after consumption. Based on therecord, this appears to be false.”

So too with the necessary implication of statements claimingbenefits against “other viruses.” “Viruses,” plural, “necessarily andunambiguously implies, in the context of an advertisement for ‘Hen Food,’ thatthere are other viruses that FeedLock defends against.” Again, the recordsupported 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 someevidence shows up in the materiality discussion), because literal falsity canbe presumed deceptive. There was direct and indirect evidence of materiality:direct from customer inquiries, which can show that a claim waspurchase-relevant, and indirect. “One of Kalmbach’s sales representativestestified that she was told by customers and potential customers that theywouldn’t consider Kalmbach’s Henhouse Reserve feed because it lacked a bird flupreventative or bird flu prevention, unlike Purina’s Farm to Flock.” (Nothearsay because not offered for the truth of the matter asserted.) Plus,Kalmbach showed that Purina “misrepresented an inherent quality orcharacteristic of the product.” Advertising virus defense is likely to induceconsumers to believe they are getting a better product than feed that does notoffer such a defense. Purina’s own internal consumer research results concludedthat such claims were “most motivating” to customers; Kalmbach’s experttestified that many consumers in this market “are more emotionally motivated tokeep their chickens alive, and are concerned by recent outbreaks of avianinfluenza,” and Purina’s expert agreed that backyard owners “are emotionallyconnected to their flock.” Purina’s senior marketing manager testified thatPurina’s consumers “started to humanize or personify their chickens, and sothey treated them like family. They were more like pets like cats and dogs.” [Ihate to ask, but, based on thisstory, I have to wonder: is MAGA going to go after antivirals in chickenfeed? Will they worry about chicken autism?]

another example

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

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

There was a presumption of irreparable injury. Purina arguedthat the presumption was rebutted here because any lost sales could be recoupedby money damages, and there was no evidence supporting “a more severe andongoing injury,” like a dealer dropping Kalmbach for Purina or reputationaldamage. It also argued that requiring it to contact its customers would be tooextreme 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 thatthere was still the distinct possibility that Kalmbach will suffer injury,which is the wrong question, but the right one probably still has the sameanswer. That’s because,

although Purina sent out threeblast emails to 130,000 recipients about Farm to Flock with statementsregarding avian influenza, it has never corrected those emails. Should any ofthose 130,000 email recipients (or any further recipients of those emails) relyon those emails, further disseminate those emails, or refer back to thoseemails today or in the future, they may believe Purina still represents thatits Farm to Flock feed helps defend against bird flu. Because it would bedifficult, if not impossible, to calculate whether Purina’s more recent salesof Farm to Flock were a result of these latent advertisements, calculatingdamages would be futile.

Purina argued that Kalmbach’s supposed delay in bringing themotion undermined any claim of irreparable harm. Kalmbach learned aboutPurina’s advertisements in April and sued in early June; that wasn’t asufficient delay to undermine Kalmbach’s claim of irreparable injury,especially given that Kalmbach would need some time to evaluate the scientificclaims.

Harm to Purina/balance of equities: Purina stopped furtherpublication but didn’t issue corrective statements. Purina argued that a publicretraction would risk damaging its reputation. At the preliminary injunctionstage, a court order proclaiming its ads were “unsupported and untrue” woulderode 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 tailoredthe injunction to avoid some of Kalmbach’s proposed harshness.

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

“Purina’s argument is mainly that requiring any publicstatement on Purina’s part would be too extreme, and Purina points to caseswhere courts ordered much more tailored relief.” The lesson was that “retractionsshould be issued in instances where identifiable third parties received thechallenged claim,” and here those were emails. “Just because Purina hasaddressed some forms of its prior advertisements does not mean that allconfusion will have dissipated. Thus, Purina must issue some form of a retraction.”

But the court would limit the language. The antivirus claimwas false “for the purposes of the Lanham Act and the Ohio Deceptive TradePractices Act because Purina had no empirical support or basis for it, and thescientific consensus today suggests that it is incorrect.” But Kalmbach’sexpert testified that it is possible that avian influenza could live onchicken feed, and that if a bird ingested that infected feed, that bird couldget avian influenza. And it was an open question whether FeedLock would haveany effect on avian influenza in bird feed, or the population of birds that eatthat feed. [It’s possible that sprinkling a mix of cinnamon and cumininto the feed would protect birds; this is why the Third Circuit held thatmaking unsubstantiated claims that you have no reason to think are true countsas making literally false claims. It’s bullshit in the sense that you have nointerest in the truth value of your claim; you’re just making it to sell theproduct. 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 afinal determination of falsity, so the court required the retraction (to besent to email recipients and posted on Purina’s website) to say “At thepreliminary injunction stage, the Court found that Purina engaged in falseadvertising because these statements were not scientifically grounded andlacked a scientific basis. Purina retracts these statements, as well as anyother representation that Purina’s Farm to Flock 18% Layer Hen Food defendsagainst, protects against, prevents, mitigates, or provides immunity to theeffects of avian influenza, bird flu, or other viruses.” [Quick TOS question:does your TOS warn people who unsubscribe from your mailing list that you mighthave to contact them in the future for legal compliance?] [Quick readingcomprehension question: what percentage of consumers will consider the reputationalhit to Purina decreased because it’s just a preliminary injunction? I think thecourt did the right thing, but that doing so will not change the effects onPurina’s overall reputation one jot. Which is to say that sometimes we shouldbe happily normative about these issues.]

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