But even so, a district court's order is not final if it "remand[s] for significant further proceedings in bankruptcy courts." In re Decor Holdings, Inc., 86 F.4th 1021, 1024 (2d Cir. 2023) (per curiam); see also Penn Traffic, 466 F.3d at 77-78. Therefore, even under the flexible approach to finality, a district court's order reversing and remanding a bankruptcy court's dismissal of an adversary proceeding for lack of subject matter jurisdiction is not a final decision.
Petrello v. White, 533 F.3d 110, 113 (2d Cir. 2008). Although a "more flexible concept of 'finality' is applied" in bankruptcy, In re Penn Traffic Co., 466 F.3d 75, 77 (2d Cir. 2006) (per curiam), a district court's order is not final if it "remand[s] for significant further proceedings in bankruptcy courts," In re Décor Holdings, Inc., 86 F.4th 1021, 1024 (2d Cir. 2023) (per curiam). Whether a district court's order requires significant further proceedings in bankruptcy court sometimes turns on whether the underlying bankruptcy order was itself final.