California Code, Streets and Highways Code - SHC § 36524

(a) At the public hearing, the city council shall hear and consider all protests against the establishment of the area, the extent of the area, or the furnishing of specified types of improvements or activities within the area. A protest may be made orally or in writing by any interested person. Any protest pertaining to the regularity or sufficiency of the proceedings shall be in writing and shall clearly set forth the irregularity or defect to which the objection is made.

(b) Every written protest shall be filed with the clerk at or before the time fixed for the public hearing. The city council may waive any irregularity in the form or content of any written protest and at the public hearing may correct minor defects in the proceedings. A written protest may be withdrawn in writing at any time before the conclusion of the public hearing.

(c) Each written protest shall contain a description of the business in which the person subscribing the protest is interested sufficient to identify the business and, if a person subscribing is not shown on the official records of the city as the owner of the business, the protest shall contain or be accompanied by written evidence that the person subscribing is the owner of the business. A written protest which does not comply with this section shall not be counted in determining a majority protest.