An Illinois family has filed a class action lawsuit against Blue Buffalo Company Ltd. after losing their 10-year-old dog, Maya, to dilated cardiomyopathy. The suit claims that the company marketed its grain-free diets as healthy despite evidence linking them to the heart condition.
Filed in the U.S. District Court for the Northern District of Illinois, the complaint cites U.S. Food and Drug Administration reports from a previous investigation into the link between grain-free diets and non-hereditary DCM. The lawsuit alleges that grain-free products manufactured by Blue Buffalo have repeatedly been linked in scientific research and FDA investigations to diet-related DCM and other heart conditions in dogs.
The lawsuit cites multiple complaints to the FDA regarding this link, in addition to research showing that grain-free diets containing high concentrations of peas and pulses may interfere with the absorption of taurine, an amino acid critical to myocardial health. The filing also mentions research showing that dogs with non-hereditary DCM improved after transitioning to grain-inclusive diets and receiving additional taurine.
Plaintiffs Ryan and Diana Walsh say they fed Maya Blue Buffalo Wilderness Chicken Recipe Adult High-Protein Grain-Free Dry Dog Food for years based on the company’s health-focused marketing. Maya was diagnosed with DCM in 2023 and died of congestive heart failure in October 2024.
The lawsuit claims that Blue Buffalo was aware of the potential link to DCM from internal research, published studies, and FDA consumer reports, but still promoted their grain-free formulas as premium, health-supporting options.
“This case is about a large corporation marketing a product as the ‘best pet food possible, made with the finest natural ingredients’ while ignoring evidence of serious health risks,” said Simeon Genadiev of The G Law Group, which filed the suit along with co-counsel Florek Law. “When corporations make that choice, they must be held accountable.”
The proposed class action could include millions of pet owners who purchased Blue Buffalo grain-free dog foods based on the company’s marketing claims. The suit seeks damages to cover the cost of Maya’s food, veterinary care, and medications, and demands changes to Blue Buffalo’s marketing and consumer messaging.