California Code, Business and Professions Code - BPC § 7583.17

(a) Upon approval of an application for registration, the chief shall cause to be issued to the applicant at his or her last known residential address a registration card in a form approved by the director.

(b) A person may work as a security guard or security patrolperson pending receipt of the registration card if he or she has been approved by the bureau and carries on his or her person a hardcopy printout of the bureau's approval from the bureau's Internet Web site and a valid picture identification.

(c) This section shall become operative on July 1, 2018.