Section 22. Building loan contract

A building loan contract either with or
  without the sale of land, and  any  modification  thereof,  must  be  in
  writing  and  duly acknowledged, and must contain a true statement under
  oath, verified by the borrower, showing the consideration paid, or to be
  paid, for the loan described therein, and showing all other expenses, if
  any, incurred, or to be incurred in connection therewith,  and  the  net
  sum available to the borrower for the improvement, and, on or before the
  date  of  recording the building loan mortgage made pursuant thereto, to
  be filed in the office of the clerk of the county in which any  part  of
  the  land  is  situated,  except that any subsequent modification of any
  such building loan contract so filed must be filed within ten days after
  the execution of any such modification. No such building  loan  contract
  or  any  modification thereof shall be filed in the register's office of
  any county. If not so filed the interest of each party to such  contract
  in  the real property affected thereby, is subject to the lien and claim
  of a person who shall thereafter  file  a  notice  of  lien  under  this
  chapter.  A modification of such contract shall not affect or impair the
  right or interest of a person, who,  previous  to  the  filing  of  such
  modification  had  furnished  or contracted to furnish materials, or had
  performed or contracted to perform labor for  the  improvement  of  real
  property, but such right or interest shall be determined by the original
  contract.  The county clerk is entitled to a fee of twenty-five dollars,
  except in counties within the city of New York where the  fee  shall  be
  fifty  dollars, for filing such a contract or modification. Except where
  the  county  clerk  maintains  a  block  index,   such   contracts   and
  modifications  thereof  shall  be  indexed  in  a book provided for that
  purpose, in the alphabetical order of the names of the persons  to  whom
  such  loans  shall be made. No assignment of the moneys due or to become
  due under a building loan contract,  under  the  provisions  of  section
  twenty-six  of  this  article,  nor  any  payment  to the holder of such
  assignment, shall be or be construed to be a modification of a  building
  loan  contract within the meaning of this section, and the execution and
  delivery of a  bond  and  mortgage,  under  the  provisions  of  section
  twenty-six  of  this article, or payments thereunder, shall not be or be
  construed to be the making  of  a  building  loan  contract  within  the
  meaning of this section.
    Except  that this section shall not apply to any mortgage taken by the
  home owners' loan corporation, a corporation created  under  an  act  of
  congress,  known  as  the  "home  owners'  loan  act of nineteen hundred
  thirty-three" and  the  "home  owners'  loan  act  of  nineteen  hundred
  thirty-three as amended," and said mortgage shall have priority over any
  and  all  liens  filed  subsequent  to the date of the recording of said
  mortgage whether or not the cash and/or bonds for  which  said  mortgage
  has  been taken as security, shall have been advanced at the time of the
  execution of such mortgage or subsequent thereto, and it  shall  not  be
  necessary  to  execute  and file any building loan contract or any other
  contract, in compliance with this section or any part thereof.
    Where the county clerk indexes liens in a block index, every  building
  loan contract presented to the clerk for filing, in order to entitle the
  same  to  be  filed,  shall  contain  in the body thereof, or shall have
  endorsed thereon, a designation of the number of  every  block,  on  the
  land map of the county, which is affected by the building loan contract.
  The  county  clerk shall cause such building loan contract to be entered
  in the block index, under the block number of every block so designated.
  In cases where a building loan contract shall have  been  filed  without
  such  designation or with an erroneous designation, the county clerk, on
  presentation of proper proof thereof, shall enter such instrument in the
  proper index, under the proper block number of every block in which  the

  land  affected  is situated, and shall, at the same time, make a note of
  such entry and of  the  date  thereof  in  every  place  in  which  such
  instrument  may  have  been  erroneously  indexed,  opposite  the  entry
  thereof,  and  also  upon  the  instrument itself, if the same be in his
  possession or produced to him for the purpose, and the  filing  of  such
  instrument  shall be constructive notice as to property in the block not
  duly designated at the time of such filing only from the time  when  the
  same shall be properly indexed.
    A   county   clerk   may   adopt   a  new  indexing  system  utilizing
  electro-mechanical, electronic or any other method he deems suitable for
  maintaining the indexes.