California Code, Health and Safety Code - HSC § 103485

The order shall be made in the form and upon the blank prescribed and furnished by the State Registrar and shall become effective upon a filing of a certified copy with the State Registrar.

Every order determining the date of birth made pursuant to this chapter shall establish a presumption that the matter contained therein is a true and accurate statement of the time of birth. The presumption established by this section is a presumption affecting the burden of proof.