Cal. Civil Code § 8538

(a) The claimant may make a written request for notice of an election by the construction lender under Section 8536 not to withhold funds. The request shall be made at the time the claimant gives the construction lender the stop payment notice and shall be accompanied by a preaddressed, stamped envelope. (b) If the construction lender elects not to withhold funds under Section 8536, the lender shall, within 30 days after making the election, give notice of that fact to a claimant who has requested notice of the election under subdivision (a). The notice shall comply with the requirements of Chapter 2 (commencing with Section 8100) of Title 1. If the basis of the election is the recordation of a payment bond under Section 8600, the construction lender shall include a copy of the bond with the notice. (c) A construction lender is not liable for failure to include a copy of the bond with the notice under this section if all of the following conditions are satisfied: (1) The failure was not intentional and resulted from a bona fide error. (2) The lender maintains reasonable procedures to avoid an error of that type. (3) The lender corrected the error not later than 20 days after the date the lender discovered the violation.