a. The commissioner of finance shall, in addition to the file maintained by him or her pursuant to section 11-416 of this chapter, maintain a file of in rem cards submitted by any person having an interest in real property who is not entitled to have tax bills mailed to him or her by the commissioner of finance, including mortgagees, lienors, encumbrancers and owners who have filed owner's registration cards designating someone else to receive bills and notices. Each such in rem card shall be signed by the person filing such card or a duly authorized representative, shall contain a description of the premises by reference to the section, block and lot numbers on the tax map and shall state the date on which said card was filed, the full name and post office address of the person filing said card and the nature of the interest said person has in said premises.
b. The commissioner of finance shall mail a notice of foreclosure and any other process required by this chapter to each person who has filed an in rem card whenever the parcels to which such cards refer are included in a list of delinquent taxes filed pursuant to this chapter. However, failure to receive such notice or process shall not affect the validity of any proceeding brought pursuant to this chapter.