N.Y. Real Prop. Law § 321-A
An assignment of rent to accrue from real property, heretofore recorded, or hereafter recorded pursuant to section two hundred ninety-four-a of this chapter, must be discharged upon the record thereof, by the recording officer, upon presentation to him of a certificate signed by the assignee, or by his personal representative or his assignee, and acknowledged or proved and certified in like manner to entitle a conveyance to be recorded, specifying that the obligation secured by the assignment of rent has been satisfied or discharged, or that the assignment of rent is canceled. When so signed and acknowledged or proved and certified, such certificate may be recorded, and such certificate, the record thereof, and a certified copy of such record may be introduced in evidence in all courts of this state. The certificate of discharge, and the certificates of its acknowledgment or proof, must be recorded and filed; and a reference must be made to the book and page containing such record in the minute of the discharge of such assignment of rent, made by the officer upon the record thereof. After such discharge has been recorded the recording officer shall make and deliver to the person in whose interest such discharge of assignment of rent is executed and recorded, his certificate setting forth the names of the assignor and assignee, the liber and page at which, the time when such assignment of rent was recorded, and the date on which said assignment of rent was satisfied and discharged.
N.Y. Real Prop. Law § 321-A