Section 11-417. In rem cards; mailing notices to other interested persons

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.