2015 New York Laws
AGM - Agriculture & Markets
Article 26 - (Agriculture & Markets) ANIMALS
353-F - Companion animal piercing and tattooing prohibited.

  353-f.  Companion  animal  piercing and tattooing prohibited. 1. No
  person shall pierce or cause to have pierced a companion  animal  unless
  such  piercing  provides a medical benefit to the companion animal. Such
  piercing shall be performed by a  licensed  veterinarian  or  under  the
  supervision of a licensed veterinarian. Nothing in this section shall be
  construed to apply to ear tags on rabbits and cavies.
2. No person shall tattoo or cause to have tattooed a companion animal
  unless such tattoo:
(a) is done in conjunction with a medical procedure for the benefit of
  the  companion  animal  and  to indicate that such medical procedure has
  been done, provided that such tattoo is not for design purposes; or
(b) is done for the purpose of identification of the companion  animal
  and  not for design purposes, and such tattoo includes only such numbers
  and/or letters allotted by a corporation that, in the regular course  of
  its business, maintains an animal tattoo identification registry.
3. For the purposes of this section, "tattoo" shall mean a mark on the
  body  made  with  indelible  ink  or pigments injected beneath the outer
  layer of the skin.
4. Tattooing done in conjunction with  a  medical  procedure  for  the
  benefit of a companion animal that indicates that such medical procedure
  has been done shall be performed by a licensed veterinarian or under the
  supervision of a licensed veterinarian.
5.  Any  person  who knowingly violates the provisions of this section
  shall be guilty of a violation punishable pursuant to the penal law.