2010 New York Code
PBH - Public Health
Article 29-C - (2980 - 2994) HEALTH CARE AGENTS AND PROXIES
2985 - Revocation.

§  2985. Revocation. 1. Means of revoking proxy. (a) A competent adult
  may revoke a health care proxy by notifying the agent or a  health  care
  provider  orally or in writing or by any other act evidencing a specific
  intent to revoke the proxy.
    (b) For the purposes of this section, every adult  shall  be  presumed
  competent unless determined otherwise pursuant to court order.
    (c)  A  health  care proxy shall also be revoked upon execution by the
  principal of a subsequent health care proxy.
    (d) The creation by the principal of written  wishes  or  instructions
  about  health care, or limitations upon the agent's authority, shall not
  revoke  a  health  care  proxy  unless  such  wishes,  instructions   or
  limitations  expressly  provide  otherwise. Such wishes, instructions or
  limitations shall constitute evidence  of  the  principal's  wishes  for
  purposes  of  subdivision  two  of  section  two  thousand  nine hundred
  eighty-two of this article.
    (e) The appointment of the principal's spouse  as  health  care  agent
  shall  be  revoked upon the divorce or legal separation of the principal
  and spouse, unless the principal specifies otherwise.
    2. Duty to record revocation.  (a) A physician who is informed  of  or
  provided  with a revocation of a health care proxy shall immediately (i)
  record the revocation in the principal's medical record and (ii)  notify
  the  agent and the medical staff responsible for the principal's care of
  the revocation.
    (b) Any member of the staff of a health care provider informed  of  or
  provided  with  a  revocation  of  a  health care proxy pursuant to this
  section shall immediately notify a physician of such revocation.