California Code, Revenue and Taxation Code - RTC § 12303

(a) Every return required by this article to be filed with the commissioner shall be signed by the insurer or an executive officer of the insurer and shall be made under oath or contain a written declaration that it is made under penalty of perjury. A return of a foreign insurer may be signed and verified by its manager residing within this state. A return of an alien insurer may be signed and verified by the United States manager of the insurer.

(b) This section shall become operative on July 1, 2013.