. Although Allen’s notice of appeal was filed prior to the entry of final judgment, we have jurisdiction over Allen’s appeal from the July 25 order under the doctrine of cumulative finality. Equip. Fin. Group, Inc. v. Traverse Comput. Brokers, 973 F.2d 345, 347-48 (4th Cir. 1992).

. Allen filed his notice of appeal before the district court entered its final order on September 22, 2017, dismissing the claims against the remaining defendant. Although, in some circumstances, an informal brief filed in this court may be sufficient to give the requisite notice of intent to appeal, see Smith v. Barry, 502 U.S. 244, 248-49, 112 S.Ct. 678, 116 L.Ed.2d 678 (1992), Allen’s informal brief was not filed until November 15, 2017, after the expiration of the 30-day appeal period. See Fed. R. App. P. 4(a)(1)(A), Moreover, Allen did not obtain an extension or reopening of the appeal period. See Fed. R. App. P. 4(a)(5), (6). Because "the timely filing of a notice of appeal in a civil case is a jurisdictional requirement,” Bowles v. Russell, 551 U.S. 205, 214, 127 S.Ct. 2360, 168 L.Ed.2d 96 (2007), we lack jurisdiction to review the district court's final order.