N.Y. CVP Law § 3133

Rule 3133. Service of answers or objections to interrogatories. (a)\nService of an answer or objection. Within twenty days after service of\ninterrogatories, the party upon whom they are served shall serve upon\neach of the parties a copy of the answer to each interrogatory, except\none to which the party objects, in which event the reasons for the\nobjection shall be stated with reasonable particularity.\n (b) Form of answers and objections to interrogatories.\nInterrogatories shall be answered in writing under oath by the party\nserved, if an individual, or, if the party served is a corporation, a\npartnership or a sole proprietorship, by an officer, director, member,\nagent or employee having the information. Each question shall be\nanswered separately and fully, and each answer shall be preceded by the\nquestion to which it responds.\n (c) Amended answers. Except with respect to amendment or\nsupplementation of responses pursuant to subdivision (h) of section\n3101, answers to interrogatories may be amended or supplemented only by\norder of the court upon motion.\n