N.Y. Rac. Pari-Mut. Wag. & Breed. Law § 219
Notwithstanding any other provision of law, rule or regulation nothing herein shall be deemed to authorize the stewards or the commission to promulgate any rule or regulation that would prohibit a jockey from wearing any advertising or promotional material on his or her clothing. The wearing of such advertising or promotional material shall be permitted only when the owner of a horse for whom such jockey is riding provides the jockey with prior written authorization. Notwithstanding the foregoing, when a corporation, company or any other entity sponsors a race or race day at any franchised corporation or any racing association or corporation, such racing association may prohibit a jockey from wearing advertising material that represents a competitor of such sponsoring corporation, company or other entity.
N.Y. Rac. Pari-Mut. Wag. and Breed. Law § 219