California Code, Streets and Highways Code - SHC § 10306

The failure of the clerk to mail the notice to any property owner or the failure of any property owner to receive the notice shall not affect the validity of any proceedings taken under this division. If property assessed by the state under Section 14 of Article XIII of the Constitution is proposed to be assessed, the notice shall be mailed to every owner of the property at the address thereof shown on the last board roll transmitted to the county auditor.