See Hamm v. Rhone-Poulenc Rorer Pharmaceuticals, Inc., 187 F.3d 941, 950 (8th Cir.1999), cert. denied, — U.S. —, 120 S.Ct. 937, 145 L.Ed.2d 815 (2000). Whether that option is available to Green at the present time is questionable, however. If Fed.R.Civ.P. 23(e) applies to putative class actions before certification of the class, then court approval for the dismissal would be required in any event. See id. 19 . But see Porous Media Corp. v. Pall Corp., 186 F.3d 1077, 1079 (8th Cir.1999) (stating that a district court ruling on a Rule 12(b)(6) motion may consider materials that are "necessarily embraced by the pleadings.") (citing Piper Jaffray Cos. v. National Union Fire Ins. Co., 967 F.Supp. 1148, 1152 (D.Minn.1997)); Silver v. H & R Block, Inc., 105 F.3d 394, 397 (8th Cir.1997) (<HOLDING>); Parnes v. Gateway 2000, Inc., 122 F.3d 539,
holding that district court may consider documents referred to in plaintiffs complaint and central to his claim holding that court could consider undisputed documents upon which the plaintiff based his action holding that the district court properly dismissed an indictment where the parties argued the applicability of a statute based on a set of undisputed facts holding that a court may consider documents that have not been incorporated by reference where the complaint relies heavily upon its terms and effect which renders the document integral to the complaint holding that 1 the complaint is deemed to include any documents incorporated in it by reference and any document upon which it solely relies and which is integral to the complaint and that the court may consider such documents on a motion to dismiss pursuant to fedrcivp 12b6