ries in the complaint may not form the basis for § 1338(a) jurisdiction unless patent law is essential to each of those theories.”).
Applying these principles to the case at hand, we conclude that we have jurisdiction to entertain this appeal. As we explain below, the defendants’ contention that “all of [plaintiffs’ claims arise under the patent law because each requires [pjlaintiffs to establish that the [tamoxifen] patent was invalid or unenforceable,” Appellees’ Reply Mem. Supp. Mot. to Transfer Appeal at 2, is mistaken. The theories that would enable the plaintiffs to prevail do not require us to examine whether Judge Broderick’s invalidation of the tamoxifen patent would have been upheld on appeal or whether the tamoxifen patent was otherwise enforceable and infringed.
If the plaintiffs alleged facts that, if proved, would establish that the Settlement Agreement provided the defendants with benefits exceeding the scope of the tamoxifen patent, they would succeed in alleging an antitrust violation. And if the plaintiffs plausibly alleged that the defendants entered into an agreement to manipulate the 180-day exclusivity period to the defendants’ joint benefit, and if they were able to prove based on the facts alleged that they suffered antitrust' injury as a result of that agreement, then that, too, would likely be sufficient to state an antitrust violation. Were they to allege and then prove facts sufficient to support either of these theories, the argument that the Settlement Agreement was unlawful “[e]ven if the [tamoxifen p]atent is presumed valid and enforceable,” Compl. ¶ 55, would, in our view, be persuasive.
Because we conclude that there are “reasons completely unrelated to the provisions and purposes of the patent laws why the plaintiff[s] may or may not be entitled to the relief [they] seek[ ],” Christianson, 486 U.S. at 810, 108 S.Ct. 2166 (internal quotation marks, citation, and alterations omitted), we have jurisdiction to entertain this appeal.
II. Standard of Review
We review a decision on a motion to dismiss de novo. Gregory v. Daly, 243 F.3d 687, 691 (2d Cir.2001).
“A pleading which sets forth a claim for relief ... shall contain ... a short and plain statement of the claim showing that the pleader is entitled to relief.” Fed. R.Civ.P. 8(a)(2). “Given the Federal Rules’ simplified standard for pleading, a court may dismiss a complaint only if it is clear that no relief could be granted under any set of facts that could be proved consistent with the allegations.” Swierkiewicz v. Sorema N.A., 534 U.S. 506, 514, 122 S.Ct. 992, 152 L.Ed.2d 1 (2002) (internal quotation marks, citation, and alteration omitted). There is no heightened pleading requirement in antitrust cases. See Twombly v. Bell Atl. Corp., 425 F.3d 99, 108-13 (2d Cir.2005).
In reviewing a decision on a motion to dismiss under Federal Rule of Civil Procedure 12(b)(6), we “must accept as true all the factual allegations in the complaint,” Leatherman v. Tarrant County Narcotics Intelligence & Coordination Unit, 507 U.S. 163, 164, 113 S.Ct. 1160, 122 L.Ed.2d 517 (1993), and “draw all reasonable inferences in plaintiffs’ favor,” Freedom Holdings Inc. v. Spitzer, 357 F.3d 205, 216 (2d Cir.2004). To survive a motion to dismiss, a plaintiff bringing suit under section 1 of the Sherman Act need not allege facts that exclude the possibility that the behavior of which complaint is made is legal. See Twombly, 425 F.3d at 111 (“[S]hort of the extremes of ‘bare bones’ and ‘implausibility,’ a complaint in an antitrust case need