New York Uniform Commercial Code Law Section 3-307 - Burden of Establishing Signatures, Defenses and Due Course.

Section 3--307. Burden  of  Establishing  Signatures,  Defenses  and Due
                Course.
(1) Unless specifically denied in the pleadings each signature  on  an
  instrument  is admitted. When the effectiveness of a signature is put in
  issue
     (a) the burden of establishing it is on the party claiming  under
         the signature; but
     (b) the  signature is presumed to be genuine or authorized except
         where the action is to enforce the obligation of a  purported
         signer  who  has  died  or become incompetent before proof is
         required.
(2) When signatures are admitted or  established,  production  of  the
  instrument  entitles  a  holder  to  recover  on it unless the defendant
  establishes a defense.
(3) After it is shown that a defense  exists  a  person  claiming  the
  rights  of a holder in due course has the burden of establishing that he
  or some person under whom he claims is in all respects a holder  in  due
  course.

Last modified: February 3, 2019