Cal. Penal Code § 18205

Every person who owns or possesses a firearm or ammunition with knowledge that he or she is prohibited from doing so by a temporary emergency gun violence restraining order issued pursuant to Chapter 2 (commencing with Section 18125), an ex parte gun violence restraining order issued pursuant to Chapter 3 (commencing with Section 18150), or a gun violence restraining order issued after notice and a hearing issued pursuant to Chapter 4 (commencing with Section 18170), is guilty of a misdemeanor and shall be prohibited from having in his or her custody or control, owning, purchasing, possessing, or receiving, or attempting to purchase or receive, a firearm or ammunition for a five-year period, to commence upon the expiration of the existing gun violence restraining order.