N.Y. Comp. Codes R. & Regs. tit. 22, § 137.6
(1) Except as set forth in paragraph (2) of this subdivision, where the attorney and client cannot agree as to the attorney's fee or where the attorney seeks to commence an action against the client for attorney’s fees, the attorney shall forward a written notice to the client, entitled Notice of Client's Right to Arbitrate, by certified mail or by personal service. The notice:
(b) If the attorney forwards to the client by certified mail or personal service a notice of the client's right to arbitrate, and the client does not file a request for arbitration within 30 days after the notice was received or served, the attorney may commence an action in a court of competent jurisdiction to recover the fee and the client no longer shall have the right to request arbitration pursuant to this Part with respect to the fee dispute at issue. An attorney who institutes an action to recover a fee must allege in the complaint:
(a)