On May 11, 2023, the U.S. Court of Appeals for the 9^th Circuit affirmed the District Court’s grant of summary judgment in favor of Walmart and International Vitamin Corporation (Defendants) in a class-action lawsuit which alleged that Defendants had incorrectly labeled certain of their dietary supplement products as glucosamine sulfate or glucosamine sulfate potassium chloride (the decision does not distinguish between these alternative names). The decision was based on the fact that Plaintiffs’ allegations relied on different test methods than those prescribed by the Federal Food, Drug, and Cosmetic Act (FDCA) and its implementing regulations and that the use of such methods was preempted by the FDCA.

Under the relevant provisions of the FDCA and its implementing regulations, a food (including dietary supplement) is misbranded if it is offered for sale under the name of another food, or if it does not include certain mandatory nutrition information, including a declaration of each dietary ingredient by its common or usual name. Compliance with the nutrition labeling requirements, including the common or usual name requirement, is determined by specified testing protocols, which provide in part that testing should be conducted by an AOAC official method or, if one is not available, alternate methods that have been appropriately validated.

Plaintiffs alleged that true glucosamine sulfate potassium chloride consists of a single crystal composed of glucosamine, sulfate, potassium, and chloride, and that their testing revealed that the Defendants’ products contained a blend of glucosamine hydrochloride and potassium sulfate, which they alleged should be labeled as glucosamine hydrochloride. However, the test methodology which Plaintiff’s expert used was neither an AOAC method nor had it been appropriately validated. Furthermore, Plaintiffs’ expert acknowledged that other validated methods characterized the blended product as glucosamine sulfate potassium chloride (i.e., the validated methods did not distinguish between glucosamine sulfate potassium chloride in its blended or crystal form).

Accordingly, the Court held that Plaintiffs sought to impose a labeling requirement which was different than federal law and that their claims were therefore preempted by the FDCA.