stockholders lacked “standing” to bring such an action because the stockholders, “experiencing no direct harm, possess[ ] no primary right to sue.” Kauffman v. Dreyfus Fund, Inc., 434 F.2d 727, 732 (3d Cir.1970) (emphasis added), cert. denied, 401 U.S. 974, 91 S.Ct. 1190, 28 L.Ed.2d 323 (1971); accord EMI Ltd. v. Bennett, 738 F.2d 994, 996-97 (9th Cir.), cert. denied, 469 U.S. 1073, 105 S.Ct. 567, 83 L.Ed.2d 508 (1984); Stevens v. Lowder, 643 F.2d 1078, 1080 (5th Cir.1981). But we do not read these cases as actually turning on the question whether the stockholder has suffered a sufficiently direct injury to establish Article III injury or causation. The courts do not conduct that kind of analysis. It may well be that if a minor injury is suffered by a large corporation it would be difficult to trace a “distinct and palpable injury” to a shareholder, Warth v. Seldin, 422 U.S. 490, 501, 95 S.Ct. 2197, 2206, 45 L.Ed.2d 343 (1975), but that would certainly not be so if the damage was to a closely held corporation. Conceptually, then, the problem is not an Article III one. See Association of Data Processing Serv. Orgs., Inc. v. Camp, 397 U.S. 150, 152, 90 S.Ct. 827, 829, 25 L.Ed.2d 184 (1970) (economic injury satisfies Article III).
Standing and real-party-in-interest questions do overlap to the extent that both ask whether the plaintiff has a personal interest in the controversy. See 6A C. Wright, A. Miller & M. Kane, Federal Practice and Procedure § 1524, at 329-30 (1990). But the question whether the suit should be brought by the Whelans or the Corporation really depends, as we have noted, on considerations and conventions of corporate law — whether the corporation should be entitled to bring an action, at least in the first instance, without the distraction of stockholders’ suits — which we think are brought into play under Rule 17(a) of the Federal Rules of Civil Procedure.
Rule 17(a) states that “[ejvery action shall be prosecuted in the name of the real party in interest.” Fed.R.Civ.P. 17(a). In other words, the action must be brought by the person entitled under the governing substantive law to enforce the asserted right. See District of Columbia ex rel. American Combustion, Inc. v. Transamerica Ins. Co., 797 F.2d 1041, 1048 (D.C.Cir.1986). A real-party-in-interest defense can be raised as a Rule 12(b)(6) motion, stating, in effect, that because the plaintiff is not the person who should be bringing the suit, the plaintiff has “fail[ed] to state a claim upon which relief can be granted.”7 Fed.R.Civ.P. 12(b)(6). And a Rule 12(b)(6) motion can be raised at trial. See id. 12(h)(2). Rule 17(a), however, provides that “[n]o action shall be dismissed on [real-party-in-interest grounds] until a reasonable time has been allowed after objection for ratification of commencement of the action by ... the real party in interest.” Id. 17(a). This implies that the defense may not be raised at any time, for the real party must have the opportunity to step into the “unreal” party’s shoes and should not be prejudiced by undue delay. See 6A C. Wright, A. Miller & M. Kane, § 1554, at 407 (“Regardless of what vehicle is used for presenting the objection [12(b)(6) motion or 8(c) defense], it should be done with reasonable promptness.”). For this reason, we hold that where a Rule 17(a) defense is made, judges abuse their discretion in allowing the plea as late as the start of the trial if the real party has been prejudiced by the defendant’s laxness. See, e.g., Gogolin & Stelter v. Karn’s Auto Imports, Inc., 886 F.2d 100, 102-03 (5th Cir.1989) (Rule 17(a) defense waived when made at the close of the plaintiff’s evidence), cert. denied, 494 U.S. 1031, 110 S.Ct. 1480, 108 L.Ed.2d 617 (1990); Hefley v. Jones, 687 F.2d 1383, 1388 (10th Cir.1982) (defense waived when made sixteen days before trial).
In this case, Rule 17(a) “ratification” was impossible because Abell and Toomey did not raise the real-party-in-interest issue until the trial was underway. The prejudice here is particularly acute because the Corporation, the alleged real party in interest, was in the hands of a bankruptcy trustee. The considerable lapse of time (not to mention the numerous adverse rulings the district court had made before the trial had even begun) may have hampered the Whe-
7
We note that the question how a Rule 17(a) defense is raised (as a 12(b)(6) motion or as a Rule 8(c) affirmative defense) remains unsettled. See 6A C. Wright, A. Miller & M. Kane, § 1554, at 405-09.