Cal. Health & Safety Code § 25993.1

It shall be a defense to any action to enforce subdivision (b) of Section 25990 that a business owner or operator relied in good faith upon a written certification by the supplier that the whole veal meat, whole pork meat, shell egg, or liquid eggs at issue was not derived from a covered animal who was confined in a cruel manner, or from the immediate offspring of a breeding pig who was confined in a cruel manner.