2006 New York Code - Alteration.

 
  Section 3--407. Alteration.
    (1)  Any  alteration  of  an  instrument is material which changes the
  contract of any party thereto in any respect, including any such  change
  in
         (a) the number or relations of the parties; or
         (b) an  incomplete instrument, by completing it otherwise than as
             authorized; or
         (c) the writing as signed, by adding to it  or  by  removing  any
             part of it.
    (2) As against any person other than a subsequent holder in due course
         (a) alteration  by  the  holder  which  is  both  fraudulent  and
             material discharges  any  party  whose  contract  is  thereby
             changed  unless  that  party  assents  or  is  precluded from
             asserting the defense;
         (b) no other alteration discharges any party and  the  instrument
             may  be  enforced  according  to its original tenor, or as to
             incomplete instruments according to the authority given.
    (3) A subsequent holder in due course may in  all  cases  enforce  the
  instrument  according  to  its  original  tenor,  and when an incomplete
  instrument has been completed, he may enforce it as completed.