California continues to ban the domestic ferret (Mustela putorius furo), even though the National Institutes of Health (NIH), the U.S. Department of Agriculture (USDA), and California’s own Civil Code all recognize domestic animals as lawful property. NIH researchers emphasize that ferrets diverged from the polecat over 2,500 years ago and are now indispensable in biomedical research tied to more than $12 billion in federal funding. Petition 2025‑003 challenges California’s outdated classification, asking the state to align its policy with modern science and federal recognition.