California Code, Public Resources Code - PRC § 29507

(a) No person who has obtained a vested right in a development prior to January 1, 1978, or who has obtained a valid permit for development from the commission pursuant to Title 7.2 (commencing with Section 66600) of the Government Code or from the commission or any local government pursuant to former Chapter 9 (commencing with Section 1850) of Division 2 of the Fish and Game Code shall be required to secure a permit for the development pursuant to this division.  However, no substantial change may be made in any such development or with respect to the activity authorized by such a permit without prior approval having been obtained under this division.

(b) Any person who claims a vested right in a development and thereby an exemption from the requirements of this division shall, on or before January 1, 1979, notify the commission in writing by filing a claim of exemption with the commission.  If any person does not file a claim of exemption on or before that date the development of such person shall be subject to the approval requirements of this division.

(c) The commission shall establish, by regulation, procedures, including public hearings, for determining claims of exemption and may require documentation or other competent evidence, including declarations under penalty of perjury or affidavits, to support any such claim.

(d) The commission shall take reasonable steps to notify persons of the provisions of this section, but the fact that any person did not receive such notice shall not extend the period within which a claim of exemption must be filed under this section.