California Code, Business and Professions Code - BPC § 9880.2

(a) An employee of an automotive repair dealer if the employee repairs motor vehicles only as an employee.

(b) A person who solely engages in the business of repairing the motor vehicles of one or more commercial, industrial, or governmental establishments.

(c) A person who is registered pursuant to Chapter 20 (commencing with Section 9800) and whose work is limited to the installation or replacement of a motor vehicle radio, antenna, audio recorder, audio playback equipment, ignition interlock device, or burglar alarm.

(d) A person whose primary business is the wholesale supply of new or rebuilt automotive parts who solely engages in the remachining of individual automotive parts without compensation for warranty adjustments to those parts and who does not engage in repairing or diagnosing malfunctions of motor vehicles or motorcycles.  “Primary business” means the business that accounts for the majority of the company's gross sales.  “Wholesale supply” means the sale, by a seller who possesses a California Resale Permit, of automotive parts to a retailer or jobber for the purpose of resale.  However, a person described in this subdivision, prior to commencing work, shall do both of the following: