28 USC Appendix Rule 42 - Voluntary Dismissal

(a) Dismissal in the District Court. Before an appeal has been docketed by the circuit clerk, the district court may dismiss the appeal on the filing of a stipulation signed by all parties or on the appellants motion with notice to all parties.
(b) Dismissal in the Court of Appeals. The circuit clerk may dismiss a docketed appeal if the parties file a signed dismissal agreement specifying how costs are to be paid and pay any fees that are due. But no mandate or other process may issue without a court order. An appeal may be dismissed on the appellants motion on terms agreed to by the parties or fixed by the court.