California Code, Government Code - GOV § 66499.52

(a) Whenever any city, town or subdivision of land is platted or divided into lots or blocks, and whenever any addition to any city, town or subdivision is laid out into lots or blocks for the purpose of sale or transfer, the city engineer or the county surveyor, under the direction and with the approval of the city council or board of supervisors, may make an official map of the city, town or subdivision, giving to each block on the map a number, and to each lot or subdivision in the block a separate number or letter, and giving names to the streets, avenues, lanes, courts, commons or parks, as may be delineated on the official map.

(b) In a city or county which has adopted the procedure prescribed herein, any surveyor or engineer, under the review of the city engineer or county surveyor, may prepare an official map to be filed for record pursuant to subdivisions (d) and (e) of Section 66499.35. The map shall be prepared in accordance with the map format specifications of subdivisions (a) to (f), inclusive, of Section 66434. Payment for the services of the city engineer or county surveyor, and any charges required by local ordinance to be paid for the cost of processing the official map by the city engineer or county surveyor, shall be the responsibility of the applicant. The official map shall include an engineer's or surveyor's certificate stating that the map was prepared pursuant to the provisions of this section, and an approval certificate of the city engineer or county surveyor.The certificate shall be signed, and, below or immediately adjacent to the signature, indicate the license or registration number with expiration date of the registered civil engineer or licensed land surveyor preparing and approving the official map.