concurring in part and concurring in the judgment.
I am unable to join in the holding in Part II of the court’s opinion, concerning Conrail’s attempt alternatively to substitute as a petitioner or to intervene. Under the unique circumstances of this case, I would accept Conrail's motion as one for intervention and, for good cause shown, would exercise our undoubted discretion to extend the time for its filing. This would, of course, place Conrail's attack on the Commission’s statutory authority squarely before us, and I would sustain ICC’s action as well within its powers in light of the statutory gap left by Congress regarding changes in the rail cost adjustment factor to account for deflation. Accordingly, and because I agree with my colleagues' analysis of the challenges made by the shipper-petitioners, I would affirm the Commission in all respects.
I see no barrier, jurisdictional or otherwise, to Conrail’s participation in the proceeding before us. Jurisdiction to entertain this proceeding is clearly derived from the protesting shippers’ timely petitions for judicial review of the Commission’s rule-making order. Congress has expressly provided that in any “proceeding to enjoin or suspend, in whole or in part, a rule, regulation, or order of the ... Commis*407sion,” 1 (a) those “interested in the controversy or question before the Commission,” 2 as well as (b) those “whose interests are affected by the order of the agency,” 3 may intervene in the review proceeding.4 And while motions for leave to intervene ordinarily must be filed within 30 days after filing of the petition for review,5 we have full authority to enlarge the time for intervention when good cause therefore has been shown.6
Unlike the court today, I believe that allowance of Conrail’s intervention in the present proceeding would in no way conflict with our decision in Simmons v. ICC.7 That case involved an effort by an intervenor to continue a review proceeding sought to be launched by an untimely petition for review. Since no other petition for review was ever filed, our jurisdiction depended wholly upon the status of the intervenor. We held that “[a]n intervenor lacking an independent jurisdictional basis cannot maintain suit where the court lacked original subject matter jurisdiction.”8 This case is in a different posture; we received timely petitions for review by parties with standing, and thus have long since been invested with subject-matter jurisdiction. In Simmons, both the petition for review and the motion for intervention were filed beyond the statutory 60-day period for inauguration of judicial review,9 with the result that jurisdiction never attached. Because we already have jurisdiction here by virtue of timely petitions for review by other parties, the question remaining is whether a sound exercise of our discretion leads to allowance of Conrail’s late motion for intervention.
Furthermore, Simmons expressly distinguished the Third Circuit’s decision in United States Steel Corp. v. EPA,10 in which an intervenor was permitted to continue a review proceeding after a party, whose timely petition for review had alone provided subject-matter jurisdiction, voluntarily dismissed that petition. Indeed, the case before us does not call for a holding nearly as broad as that announced in United States Steel. The intervenor there was let into the case after the sole petitioner for review had dropped out; thus, but for the allowance of intervention, the case would have come to an end. Here, however, the shipper-petitioners are still actively pursuing judicial review; unlike the situation in United States Steel, no one need depend on Conrail, the would-be intervenor, to keep this litigation alive.
My colleagues point to two features assertedly differentiating United States Steel from our case, but neither strikes me as a basis for denying Conrail’s intervention. It is true that the motion for intervention in United States Steel was presented within 30 days of the filing of the peti*408tion for review and thus was timely,11 but this is immaterial in light of our power to enlarge the 30-day period for good cause. Beyond that, the intervenor’s stance on the merits in United States Steel did not coincide fully with that of the petition for review, thus making intervention necessary to protect the intervenor’s interests. Early on, the intervenor knew that the petitioner would not adequately represent its position on review, and with that circumstance, a failure to timely move for intervention would have been difficult to excuse. The facts in the case at bar, however, put a different slant on the timeliness issue. Conrail believed that the Association of American Railroads (AAR), a petitioner, would continue to represent it on review as it had throughout the administrative stage, and learned the contrary only after the deadline for intervention had passed.
In sum, to say that United States Steel does not apply because Conrail’s motion for intervention was untimely begs the question. The facts of the two cases just do not translate from one context to the other. In my view, the applicability of United States Steel is not diminished by the mere fact that the motion was timely there but untimely here.
My colleagues also express concern about overstating the scope of United States Steel because the court there grounded its holding on the record before it, noting that the intervenor had registered its objections with the agency and that the motion to intervene “clearly set forth [the intervenor’s] position.” 12 I am unable to grasp the relevance of these observations to the case before us save that the United States Steel court was guarding against the possibility of an intervenor continuing a review on the basis of a position not adequately presented to the agency. That is not the case here, where Conrail’s statutory challenge is identical to that previously made by AAR before the Commission. The agency cannot claim surprise by the arguments advanced by Conrail, and the issues it would litigate are not expanded beyond those raised by the original petitioners for review.
More fundamentally, and despite factual variations between United States Steel and our case, the same decisional rationale is equally applicable in both. In United States Steel, the court reasoned as follows: Jurisdiction to review attached when the petition there was filed. Intervention was sought not to cure a jurisdictional defect, but rather to ensure that the intervenor’s interests would be adequately protected in an ongoing proceeding. The agency was on notice that a major industry was challenging the regulations, and that another party — the intervenor — was attacking the same regulations. Therefore, the court allowed the intervenor to continue with the review. Not only are all of those factors present here, but there also is the added consideration that we have jurisdiction to review the case even aside from AAR’s timely petition therefor. The Commission cannot argue that it was unaware that a statutory challenge would be mounted. It was merely unaware that it would be made by Conrail rather than by AAR.
There can be no doubt that Conrail fits the description of a party entitled to intervene — a “corporation[ ] .,. whose interests are affected by the order of the agency ...”13 — and is as much interested in this review proceeding as it was in “the controversy or question” formerly pending before the Commission.14 The only question, then, is whether there is good cause for enlarging the time for filing such a motion, and I firmly believe that there is. Conrail’s predicament is not the result of any willful disregard of a statute or rule, nor is it a consequence of negligence. Rather, Conrail was led to believe that its interests would be protected and that its position would be pressed on judicial review. The record affords no basis upon which we can fault Conrail for its failure to anticipate that AAR, its representative, would aban*409don it at the last minute. Moreover, Conrail did not know that its grievance was being abandoned by AAR until the 30-day intervention period had passed. After learning of AAR’s withdrawal of its petition for review, Conrail promptly notified the parties and the court that it wished to continue to assert the issues initially raised by AAR.
I fear that today’s decision may engender a number of undesirable practices. Members of trade and other representative associations may, quite understandably, inundate agencies with repetitive comments to ensure that their rights to petition for review and to intervene are safeguarded. Courts may be overwhelmed by duplicative petitions for review and motions for intervention to avoid the fate visited on Conrail. The benefits to agencies and courts in terms of efficiency and expediency promoted by third-party representation may largely be lost in a flood of protective paperwork.
In sum, I see no legal impediment to granting Conrail’s alternative request for intervention, and believe that good cause has been shown for enlarging the time for filing it. Accordingly, I dissent from the court’s holding in Part II, but concur in the remainder of its opinion.
. "Except as otherwise provided by an Act of Congress, a proceeding to enjoin or suspend, in whole or in part, a rule, regulation, or order of the Interstate Commerce Commission shall be brought in the court of appeals as provided by and in the manner prescribed in chapter 158 of this title." 28 U.S.C. § 2321 (1982).
. "Communities, associations, corporations, firms, and individuals interested in the controversy or question before the Commission, or in any action commenced under the aforesaid sections may intervene in said action at any time after commencement thereof." Id. § 2323.
. Id. § 2348.
. Id. §§ 2323, 2348.
. "A motion for leave to intervene or other notice of intervention authorized by an applicable statute shall be filed within 30 days of the date on which the petition for review is filed.” Fed.R.App.P. 15(d).
. "The court for good cause shown may upon motion enlarge the time prescribed by these rules or by its order for doing any act, or may permit an act to be done after the expiration of such time; but the court may not enlarge the time for filing a notice of appeal, a petition for allowance, or a petition for permission to appeal. Nor may the court enlarge the time prescribed by law for filing a petition to enjoin, set aside, suspend, modify, enforce or otherwise review, or a notice of appeal from, an order of an administrative agency, board, commission or officer of the United States, except as specifically authorized by law.” Fed.R.App.P. 26(b).
. 230 U.S.App.D.C. 236, 716 F.2d 40 (1983).
. Id. at 242, 716 F.2d at 46.
. See 28 U.S.C. § 2344 (1982).
. 614 F.2d 843 (3d Cir.1979).
. See Fed.R.App.P. 15(d), quoted supra note 5.
. 614 F.2d at 846 n. 4.
. See 28 U.S.C. § 2348 (1982).
. See notes 1-4 supra and accompanying text.