2006 New York Code - Parties To Action.

 
    §  202.  Parties to action.  There may be made parties to such action,
  all persons who would have, might  have  or  might  claim  to  have  any
  interest  in or lien upon the premises so escheated or forfeited, at the
  time of such escheat or forfeiture, and all  persons  in  possession  of
  such real property.  Where the names of the defendants are unknown, they
  may  be  designated  as  "unknown  defendants."    The provisions of law
  applicable to actions to recover  real  property  shall  apply  to  such
  actions,  except  that  service of the summons shall not be deemed to be
  complete until, pursuant to an order of the court, the summons  together
  with a notice directed to the defendants setting forth the object of the
  action,  a brief description of the land affected, the source and manner
  in and by which it  is  alleged  that  said  real  property  shall  have
  escheated or forfeited to the people, and the name or names of person or
  persons  whose  title  or  interest shall have so escheated or have been
  forfeited, shall  have  been  published  once  in  each  week  for  four
  successive  weeks  in  two  newspapers  designated in the order for such
  publication as most likely to  give  notice  to  the  defendants  to  be
  served.