Moreover, even if the district court's first forum non conveniens decision had constituted the law of the case, the district court still would have acted permissibly in departing from it. As we have explained, the “law of the case doctrine does not ... require rigid adherence to rulings made at an earlier stage of a case in all circumstances.” Murphy v. F.D.I.C., 208 F.3d 959, 966 (11th Cir.2000). In particular, we have carved out three principal exceptions to the law of the case doctrine: “when (1) a subsequent trial produces substantially different evidence (2) controlling authority has since made a contrary decision of law applicable to that issue or (3) the law-of-the-case is clearly erroneous and will work manifest injustice if not if not reconsidered.” Culpepper v. Irwin Mortg. Corp., 491 F.3d 1260, 1271 (11th Cir.2007) (quotation marks omitted)