N.Y. Real Property Actions & Proceedings Law § 904

§ 904. Permissible defendants. The plaintiff, at his election, may\nmake defendant in the action:\n 1. A tenant by the curtesy or for life or for years, of the entire\nproperty, or whoever may be entitled to a contingent or vested remainder\nor reversion in the entire property, or a person having a lien or\ninterest which attaches to the entire property. A person specified in\nthis subdivision who is not made a party is not affected by the judgment\nin the action.\n 2. A person having a lien on an undivided share or interest in the\nproperty. The nature of the lien and the share or interest to which it\nattaches shall be specified.\n 3. An unknown person entitled to an estate or interest in the property\nsold. The court shall provide for the protection of his rights, as far\nas may be, as if he were known and had appeared.\n 4. The state.\n