Rules of civil procedure in state and federal courts often provide limited circumstances under which the court may alter or amend its judgment before it becomes final and appealable. Motions (requests) to alter or amend a judgment may also be referred to as requests to modify, correct, or reform a judgment.

For example, in Federal Court, under Federal Rule of Civil Procedure 59(e), the court may alter or amend its judgment if a motion is filed within 28 days after the court enters its judgment. But the grounds upon which the court may alter or amend its judgment are generally limited to circumstances such as:

• an intervening and material change in the law that impacts the outcome of the case;

• newly discovered evidence; or

• a clear error or manifest injustice.

In New York State courts, the rules for altering or amending a judgment before it becomes final and appealable are governed by the New York Civil Practice Law and Rules (CPLR). Specifically, CPLR 5015 provides for relief from a judgment or order under certain circumstances, such as excusable default, newly discovered evidence, fraud, misrepresentation, or other misconduct by an adverse party, lack of jurisdiction, or reversal, modification, or vacatur of a prior judgment that the judgment in question relied on. A motion to vacate or modify a judgment must generally be made within one year after the judgment is entered, with some exceptions allowing for more time. In the Federal Courts, as per the Federal Rules of Civil Procedure 59(e), a party may file a motion to alter or amend a judgment within 28 days after the entry of the judgment. The grounds for such a motion are typically limited to an intervening change in controlling law, new evidence that was not previously available, or the need to correct a clear error or prevent manifest injustice.