N.Y. Real Property Actions & Proceedings Law § 637

§ 637. Action against one defendant subject to rights of others.\nWhere one or more answering defendants hold under another defendant, and\nthe plaintiff elects to proceed against the latter, subject to the\nrights and interests of the former, if the plaintiff recovers final\njudgment against the defendant under whom they hold, the judgment\noperates as a transfer to the plaintiff of that defendant's right, title\nand interest.\n