California Code, Government Code - GOV § 66499.10

Where the security is conditioned upon the payment to the contractor, his subcontractors and to persons furnishing labor, materials or equipment to them for the improvement or the performance of an act and takes the form of a deposit of money or negotiable bonds, a suit to recover the amount due the claimant may be maintained against the holder of such deposit.  Where the security takes the form of a surety bond, or surety bonds, the right of recovery shall be in a suit against the surety.  Where the security takes the form of an instrument of credit, the cause of action shall be against the financial institution obligating itself on such instrument of credit.