California Code, Government Code - GOV § 5451

(a) A pledge of collateral by any public body to secure, directly or indirectly, the payment of the principal or redemption price of, or interest on, any bonds, or any reimbursement or similar agreement with any provider of credit enhancement for bonds, which is issued by or entered into by a public body, shall be valid and binding in accordance with the terms of the pledge document from the time the pledge is made for the benefit of pledgees and successors thereto.

(b) The collateral shall immediately be subject to the pledge, and the pledge shall constitute a lien and security interest which shall immediately attach to the collateral and be effective, binding, and enforceable against the pledgor, its successors, purchasers of the collateral, creditors, and all others asserting the rights therein, to the extent set forth, and in accordance with, the pledge document irrespective of whether those parties have notice of the pledge and without the need for any physical delivery, recordation, filing, or further act.