A lawsuit against Blue Buffalo alleges the company’s grain-free dog food contributed to a pet’s development of dilated cardiomyopathy (DCM), reviving claims that have circulated since 2018 when the U.S. Food and Drug Administration announced its investigation into an alleged diet-related link. The complaint argued that the brand misled consumers about the safety of its formulations. The case continues a history of wave of litigation targeting pet food makers over formulation choices and marketing claims tied to DCM concerns.
In July 2018, the FDA publicly announced the agency’s investigation into correlations among certain dog foods and DCM. Federal authorities examined reports of DCM in dogs eating certain diets labeled as grain-free, particularly those containing peas, lentils, other legume seeds, or potatoes as main ingredients.
However, in 2022, the FDA stated it had insufficient data to establish causality among DCM case reports and pet food products eaten by afflicted dogs.
“FDA does not intend to release further public updates until there is meaningful new scientific information to share,” the agency announced in a press release on Dec. 23. 2022.
Several lawsuits have followed the FDA announcement. Similarly other lawsuits have targeted claims pet food companies make about product qualities such as natural or healthy. Here are three examples.
Lawyer analyzed US$2.6 billion DCM lawsuit against Hill’s Pet Nutrition
On February 6, 2024, KetoNatural Pet Foods filed a proposed class action lawsuit against Hill’s Pet Nutrition. The lawsuit alleged that Hill’s and a group of veterinarians worked together to manipulate the FDA into examining the potential that certain grain-free dog foods increased pets’ risk for the heart disease, DCM. The case alleged that the company’s products contributed to DCM and that the company failed to adequately warn consumers, drawing heavily on early FDA communications and public concern.
Legal analysis of the case at the time emphasized the difficulty plaintiffs face in proving causation, particularly in light of evolving and inconclusive scientific evidence. While large damage claims elevated the stakes for Hill's, the FDA’s position complicates efforts to establish liability. This challenge is directly relevant to the Blue Buffalo litigation.
Lawsuit over alleged DCM, grain-free dog food connection
In late June, 2024, a Missouri court certified a proposed class action lawsuit involving Taste of the Wild Grain-Free Dog Food. The lawsuit claimed that the defendant falsely and deceptively marketed its Taste of the Wild grain-free dog food. The lawsuit alleged that the defendant represented to consumers that its grain-free dog food was ”uniquely high-quality, safe and healthy,” but the lawsuit claimed that grain-free dog food was associated with an increased risk of developing dilated cardiomyopathy (DCM).
Like the Blue Buffalo case, the complaint focused on marketing claims and the inclusion of ingredients such as legumes, which were widely discussed during the height of DCM concern. This dynamic directly parallels the Blue Buffalo case, where the absence of causation may weaken core claims but does not eliminate litigation risk.
The Blue Buffalo case represents a resurrection of plaintiffs advancing DCM claims despite the U.S. Food and Drug Administration finding no confirmed causal relationship between diet and DCM. The persistence of these lawsuits suggests legal strategies are shifting toward arguments about consumer perception and risk disclosure, rather than relying solely on definitive scientific proof.
Purina faces lawsuit over natural claims on dog, cat food
The lawsuit against Nestlé Purina PetCare differed in focus, centering on “natural” marketing claims rather than DCM. Plaintiffs alleged that certain ingredients were inconsistent with consumer expectations of natural products, raising questions about labeling transparency and definition standards.
While not directly tied to DCM, the case was relevant to the Blue Buffalo litigation in its emphasis on marketing interpretation. Both cases reflected a broader legal environment in which pet food companies face scrutiny over how claims are communicated to consumers.
In the absence of definitive scientific conclusions, as seen in the FDA’s DCM findings or lack thereof, litigation may increasingly focus on whether marketing creates misleading impressions.
