Cal. Civ. Proc. Code § 995.410

(a) A bond becomes effective without approval unless the statute providing for the bond requires that the bond be approved by the court or officer.

(b) If the statute providing for a bond requires that the bond be approved, the court or officer may approve or disapprove the bond on the basis of the affidavit or certificate of the sureties or may require the attendance of witnesses and the production of evidence and may examine the sureties under oath touching their qualifications.

(c) Nothing shall be construed to preclude approval of a bond in an amount greater than that required by statute.