California Code, Elections Code - ELEC § 9115

(a) Within 30 days from the date of filing of the petition, excluding Saturdays, Sundays, and holidays, if, from the examination of petitions pursuant to Section 9114 shows that more than 500 signatures have been signed on the petition, the elections official may use a random sampling technique for verification of signatures. The random sample of signatures to be verified shall be drawn so that every signature filed with the elections official shall be given an equal opportunity to be included in the sample. The random sampling shall include an examination of at least 500, or 3 percent of the signatures, whichever is greater.A signature shall not be invalidated because of a variation of the signature caused by the substitution of initials for the first or middle name, or both, of the person signing the petition.

(b) If the statistical sampling shows that the number of valid signatures is within 95 to 110 percent of the number of signatures of qualified voters needed to declare the petition sufficient, the elections official shall, within 60 days from the date of the filing of the petition, excluding Saturdays, Sundays, and holidays, examine and verify the signatures filed. If the elections official determines, prior to completing the examination of each signature filed, that the petition is signed by the requisite number of qualified voters to declare the petition sufficient, the elections official may terminate the verification of the remaining unverified signatures.

(c) In determining from the records of registration, what number of valid signatures are signed on the petition, the elections official may check the signatures against facsimiles of voters' signatures, provided that the method of preparing and displaying the facsimiles complies with law.

(d) The elections official shall attach to the petition a certificate showing the result of this examination and shall notify the proponents of either the sufficiency or insufficiency of the petition.

(e) If the petition is found insufficient, no action shall be taken on the petition. However, the failure to secure sufficient signatures shall not preclude the filing later of an entirely new petition to the same effect.

(f) If the petition is found to be sufficient, the elections official shall certify the results of the examination to the board of supervisors at the next regular meeting of the board.