Appellate Court Rules Hill’s Pet Food Lawsuit Will Continue

In February 2024, Keto Natural Pet Food – a small, independently owned manufacturer of grain-free pet foods – filed a lawsuit against Hill’s Pet Food claiming that Hill’s and partner veterinarians fabricated a connection between grain-free and small brand pet foods to DCM (dilated cardiomyopathy) in dogs. 

The initial lawsuit explains a scheme that on the surface seems hard to believe. Would a major US pet food manufacturer (Hill’s) actually plan and participate in a detailed scheme to deceive the public, veterinarians, and even the FDA all for money/market share? 

“This lawsuit concerns an egregious, wide-ranging, and damaging campaign of coordinated, for-profit, faux-scientific misinformation by a large corporation. They carried out a scheme to falsely convince American dog owners that a massive, unrelated, and hugely diverse group of dog food products—essentially any product made by any of the hundreds of independent firms that were collectively eroding Hill’s market share—all increase the risk and severity of a deadly canine heart disease called dilated cardiomyopathy (“DCM”).”

But…when you read the 124 page initial complaint, every twist and turn in the plot is provided in great detail and is well documented. If you overlook the legal language, it almost reads like a good mystery novel. (We encourage all pet owners to read the full initial complaint, it is quite a pet food industry education. Click Here.) From cherry-picking DCM cases that met the desired outcome, to building a network of knowing and unknowing partners (including FDA) to further the scheme – this lawsuit brings out into the light what (potentially) some companies will do to increase sales and squash their competitors.

The court initially dismissed this lawsuit, but Keto Natural appealed. The Appeals Court has determined the case against Hill’s Pet Food will continue. Click Here to read the Appeals Court decision.

Hill’s Pet Food argued that their various statements regarding the claimed link between grain-free pet foods and small manufacturer made pet foods to DCM in dogs were not “commercial speech” and were true. An example of Hill’s statements on their website stated: “trends” such as “grain-free, raw, vegan, farm-to-table, plant-based, or homemade” dog foods can “pose health risks for dogs”. But the Appeals court disagreed with Hill’s stating: “KetoNatural has plausibly alleged that some statements and links on Hill’s’ webpages are commercial speech. KetoNatural has also plausibly alleged that these statements are literally false.”

In hindsight, many people at the time questioned if the claimed link between DCM in dogs to grain-free pet foods and small manufacturer made pet foods was legitimate. After all, at its foundation – what they were claiming was that corn in dog food was some kind of a magical super food that prevented heart disease. And they were claiming that only pet foods with corn made by the largest manufacturers (Hill’s, Purina, Mars) were safe. 

But…the alleged scheme worked. And worked well. In part due to the alleged scheme drawing in the FDA and some veterinary nutritionists. To this day, some veterinarians still believe that corn prevents DCM in dogs and only Hill’s, Purina and Mars can manufacture a ‘safe’ pet food.

An interesting twist…

Even though they allegedly manipulated the DCM in dogs link to grain-free pet food, Hill’s Pet Food is in part responsible for proving that DCM in dogs is not scientifically linked to grain-free pet food.

A study published in July 2025 titled “Different carbohydrate sources in dog foods supported overall health and cardiac function: an 18-mo prospective study in healthy adult dogs” found no evidence that grain free pet foods were linked to DCM in dogs. “Both grain-free and grain-inclusive diets providing complete and balanced nutrition supported normal cardiac function in healthy adult dogs in an 18-mo study.“

“The study was funded by Hill’s Pet Nutrition, Inc. All authors are current or past employees of Hill’s Pet Nutrition, Inc.“

“This study was a prospective, double-blind, randomized, parallel-group trial conducted between December 2, 2019, and August 25, 2021.”

Note the dates above. The study was not published until 4 years AFTER the feeding trial was complete. The feeding trial was completed in August 2021, but they waited four long years to publish the results (July 2025) that evidenced grain-free dog food was not linked to DCM – long after the FDA stopped investigating the issue and the media stories stopped.

Why did it take four years for the Hill’s Pet Food scientists to share their results with the pet owning public and veterinarians?

Personal note: This lawsuit will be VERY interesting to watch play out. It will give pet owners an inside look into what some manufacturers will do to make money – the lengths they go through, the schemes they develop to manipulate the public.

Keto Natural Pet Food had the courage to take the issue to court, to hold those who allegedly put this scheme together accountable. Our thanks to this brave company.

Susan Thixton
Pet Food Consumer Advocate
TruthaboutPetFood.com
Association for Truth in Pet Food

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