Section 209 of RA 7160

SEC. 209. Duty of Registrar of Deeds to Apprise Assessor of Real Property Listed in Registry. - (a) To ascertain whether or not any real property entered in the Registry of Property has escaped discovery and listing for the purpose of taxation, the Registrar of Deeds shall prepare and submit to the provincial, city or municipal assessor, within six (6) months from the date of effectivity of this Code and every year thereafter, an abstract of his registry, which shall include brief but sufficient description of the real properties entered therein, their present owners, and the dates of their most recent transfer or alienation accompanied by copies of corresponding deeds of sale, donation, or partition or other forms of alienation. (b) It shall also be the duty of the Registrar of Deeds to require every person who shall present for registration a document of transfer, alienation, or encumbrance of real property to accompany the same with a certificate to the effect that the real property subject of the transfer, alienation, or encumbrance, as the case may be, has been fully paid of all real property taxes due thereon. Failure to provide such certificate shall be a valid cause for the Registrar of Deeds to refuse the registration of the document.