N.Y. RPA Law § 916

§ 916. Interlocutory judgment directing partial partition. Where the\nright, share and interest of a party has been ascertained, and the\nrights, shares or interests of the other parties as between themselves\nremain unascertained, an interlocutory judgment for a partition shall\ndirect a partition as between the party whose share has been so\ndetermined and the other parties to the action. Where the rights, shares\nand interests of two or more parties have been thus ascertained and\ndetermined, the interlocutory judgment may also direct the partition\namong them of a part of the property proportionate to their aggregate\nshares. In either case, the court, from time to time, as the other\nrights, shares and interests are ascertained, may render an\ninterlocutory judgment directing the partition, in like manner, of the\nremainder of the property. Where an interlocutory judgment is rendered\nin a case specified in this section, the court may direct the action to\nbe severed, and final judgment to be rendered with respect to the\nportion of the property set apart to the parties whose rights, shares\nand interests are determined, leaving the action to proceed as against\nthe other parties with respect to the remainder of the property; and if\nnecessary, the court may direct that one of those parties be substituted\nas plaintiff.\n