California Code, Business and Professions Code - BPC § 2400

Corporations and other artificial legal entities shall have no professional rights, privileges, or powers. However, the Division of Licensing may in its discretion, after such investigation and review of such documentary evidence as it may require, and under regulations adopted by it, grant approval of the employment of licensees on a salary basis by licensed charitable institutions, foundations, or clinics, if no charge for professional services rendered patients is made by any such institution, foundation, or clinic.