Cal. Rev. & Tax. Code § 4913

If a credit is canceled on unintended property, the tax collector shall notify the assessee or agent of the assessee of the unintended property by registered mail at his last known address respecting the proposed transfer.

If the credit on the unintended property is canceled and transferred pursuant to Section 4911.1, the tax collector shall inform the person owning the unintended property immediately before issuance of the guaranty or certificate of title that the credit has been canceled and transferred and the person so notified shall be personally liable for the amount so transferred which shall be collected in the manner specified for the collection of taxes on the unsecured roll.