Royal Canin manufactures a brand of dog food available only with a veterinarian’s prescription, and it’s sold at a premium price. Anastasia Wullschleger purchased their dog food thinking it contained medication not found in off-the-shelf products, but she later learned it didn’t. Wullschleger initially filed her suit in Missouri state court, alleging that Royal Canin’s dog food is ordinary dog food and that the company sells the product with a prescription solely to deceive consumers into paying an increased price. Wullschleger’s original complaint asserted claims under the Missouri Merchandising Practices Act and state antitrust law, as well as violations of the Federal Food, Drug, and Cosmetic Act (FDCA), 21 U.S.C. §301.

Royal Canin removed the case to federal court based on the FDCA claims, which set up the parties to litigate the entire case in federal court. However, Wullschleger wanted the case to be heard in state court, so she countered she amended her complaint to remove every mention of the FDCA, leaving only her state law claims behind. She then petitioned the District Court to remand the case to state court, but they denied to do so. The Eighth Circuit Court of Appeals reversed that decision and remanded the case to state court since Wullschleger’s amended complaint contained no grounds for federal jurisdiction.