California Code, Revenue and Taxation Code - RTC § 867

An assessment made pursuant to this article against real property for the year or years in which such real property escaped assessment shall not create or impose a lien or charge on such real property for taxes, interest, or penalty if (1) such real property has been transferred or conveyed to a bona fide purchaser for value prior to the date of such assessment and the showing thereof on the secured roll with the date of entry specified thereon;  or (2) such real property is subject to a lien of a bona fide encumbrance for value created and attaching prior to the date of such assessment and the showing thereof on the secured roll with the date of entry specified thereon.  In such cases, the tax collector may record with the county recorder of any county a certificate which shall set forth the name of the person who would have been the assessee in the year in which such real property escaped assessment and the amount or amounts of any such assessments and penalties.  From the date of the recording of such certificate, a lien shall be created and shall attach against any real property owned by such person in the county or counties in which any such certificates may have been recorded, which lien shall have the force, effect and priority of a judgment lien.

The tax collector, with the approval of the board of supervisors, may at any time release all or any portion of real property subject to any lien created or attaching by the recording of such a certificate from such lien or subordinate such lien to other liens and encumbrances if he or she determines that the assessment or taxes are sufficiently secured by a lien on other property belonging to the person named in such a certificate or that the release or subordination will not endanger or jeopardize the collection of such assessment or taxes.

A written certification by the tax collector to the effect that real property subject to any lien imposed by the recording of the certificate as hereinbefore provided has been released from such lien or that such lien has been subordinated to other liens shall be conclusive evidence as to any bona fide purchaser, encumbrancer, or lessee that such lien has been released or has been subordinated as set forth in such written certification.  Such written certification may be recorded with the county recorder of any county.