Cal. Government Code § 53087.4

(a) In the case of a special tax levied by a local agency on a per parcel basis, both of the following conditions shall apply: (1) A parcel created by a subdivision map approved in accordance with the Subdivision Map Act (Division 2 (commencing with Section 66410) of Title 7) shall be deemed to be a single assessment unit and shall not be deemed, on the basis of multiple assessor’s parcel numbers assigned by the assessor, to constitute multiple assessment units. (2) A parcel that has not been subdivided in accordance with the Subdivision Map Act (Division 2 (commencing with Section 66410) of Title 7) may be deemed to constitute a separate assessment unit only to the extent that that parcel has been previously described and conveyed in one or more deeds separating it from all adjoining property. (b) (1) If the parcel identified pursuant to paragraph (1) or (2) is not consistent with the property’s identification by assessor’s parcel number, it shall be the responsibility of the parcel owner to provide the local taxing jurisdiction with written notice of the correct assessor’s parcel number of taxable parcels pursuant to this section 90 days after the initial tax bill containing the tax levy. (2) The initial levy of any special tax that is initially imposed by a local agency on a per parcel basis on or after the operative date of the act adding this paragraph shall be billed on the annual property tax bill sent by the county tax collector. (c) Any parcel identified pursuant to this section shall be for tax purposes only and shall not confer any entitlement on the property. (d) This section shall not apply to any special tax levied prior to the effective date of this section.