Task: songer_initiate

What follows is an opinion from a United States Court of Appeals. Your task is to identify what party initiated the appeal. For cases with cross appeals or multiple docket numbers, if the opinion does not explicitly indicate which appeal was filed first, assumes that the first litigant listed as the "appellant" or "petitioner" was the first to file the appeal. In federal habeas corpus petitions, consider the prisoner to be the plaintiff.

OPINION OF THE COURT
HUTCHINSON, Circuit Judge.
Jules Lusardi and the other named plaintiffs (Lusardi) in this age discrimination action seek to appeal an order of the United States District Court for the District of New Jersey revoking that court’s prior conditional certification of an opt-in class. Recognizing that an action granting or denying class certification is interlocutory and generally not appealable, they ask, in the alternative, that we exercise our jurisdiction under the All Writs Act, 28 U.S.C.A. § 1651 (West 1966), and issue a mandamus to the district court directing it to continue the class certification. On the merits, Lu-sardi asserts a number of errors by the district court in revoking certification, none of which we can reach unless we either have appellate jurisdiction or decide that a writ of mandamus is warranted.
For the reasons that follow, we hold that we lack appellate jurisdiction. We also hold that the action of the district court, with one exception, does not present us with a clear error of law and the absence of any alternative remedy, both of which conditions must be met before we have discretion to grant mandamus. Therefore, we will dismiss the appeal for lack of jurisdiction. We will, however, grant mandamus for the limited purpose of directing the district court to vacate its holding on the necessity of timely individual administrative filings of charges of age discrimination by the persons it has held do not constitute a proper opt-in class; to reconsider its order decertifying the class for disparate defenses without relying on the presence, or absence, of individual administrative charges or their timing; and, if the court nevertheless concludes class decertification is required, to modify the form of notice it directed be sent to the members of the putative opt-in class by eliminating any implication that they may be barred from pursuing remedies for asserted age discrimination because they failed individually to file timely administrative claims with the Equal Employment Opportunity Commission (EEOC).
I.
Jules Lusardi and three other former employees filed a class action against the Xerox Corporation (Xerox) on March 8, 1983, pursuant to § 7 of the Age Discrimination in Employment Act (ADEA), 29 U.S.C.A. §§ 621-634 (West 1985 & Supp.1988). The second amended class action complaint, filed October 6, 1983, alleges that Xerox has a nationwide policy and practice of using age as a determinate factor in carrying out salaried workforce reductions. Lusardi sought class certification, injunctions restraining Xerox from continuing to implement age-based corporate policies, an order directing it to implement an affirmative action program, reinstatement of plaintiffs and opt-in members of the putative class to positions comparable to those they held with Xerox before the alleged discriminatory pattern affected them individually, backpay, other pecuniary damages and costs. The class was conditionally certified by the district court on January 30, 1984 and included:
All salaried employees in the forty (40)-seventy (70) age group who in the period May 1, 1980 through March 31, 1983 have been terminated or required to retire from employment at an age less than seventy or have been denied equal employment opportunities for promotion at any unit, division or American subsidiary of Xerox Corporation and who contend that such termination, retirement or denial of promotion was caused by age discrimination policies or practices of Xerox Corporation.
App. at 180. The conditional certification was made without prejudice to the parties’ rights to move for decertification or enlargement or modification of the class or the order. On February 1, 1984, Xerox appealed the district court’s order and petitioned for a writ of mandamus, arguing that the district court erred in (1) ordering Xerox to provide to the court the names and addresses of all potential class members and authorizing Lusardi to send notice to such potential class members and (2) conditionally certifying an across-the-board opt-in class.
This court denied Xerox’s petition for mandamus by order dated February 9,1984 and in a published opinion dismissed Xerox’s appeal for lack of jurisdiction. See Lusardi v. Xerox Corp., 747 F.2d 174 (3d Cir.1984) (hereinafter Lusardi I). After concluding that the district court’s order was appealable only if it fell within the “collateral order” exception of Cohen v. Beneficial Indus. Loan Corp., 337 U.S. 541, 69 S.Ct. 1221, 93 L.Ed. 1528 (1949), we analyzed each issue separately in light of Cohen’s three requirements that: (1) the order conclusively determine the disputed question, (2) it resolve an important issue completely separate from the merits of the action, and (3) it be effectively unreviewable on appeal from final judgment. Lusardi I, 747 F.2d at 176 (quoting Coopers & Lybrand v. Livesay, 437 U.S. 463, 98 S.Ct. 2454, 57 L.Ed.2d 351 (1978)). Xerox’s argument regarding conditional class certification failed to meet the first prong of Cohen because the district court’s order was subject to revision. Id. at 177. The district court’s order requiring Xerox to provide a mailing list of potential class plaintiffs and authorizing plaintiffs to send them notice was not appealable because it was “essentially a discovery device” and therefore interlocutory. Id. at 178.
The parties agreed to randomly select a fifty-one class member “sample group” out of the thirteen hundred persons who responded to the initial notice and opted in. After making the selection, they entered into intensive discovery. It focused on both the sample group and the thirteen plaintiffs named in the second amended complaint. Lusardi’s motion to file a third amended complaint to add a fourteenth named plaintiff and thereby expand the class period to include April 1, 1983 through May 1, 1984, as well as to add class-wide allegations of state contract and age discrimination claims, was denied by Magistrate Ronald Hedges on June 2, 1986 and by the district court on June 17, 1986.
Upon the completion of discovery, Xerox moved to decertify the conditional class. Lusardi filed a cross-motion for summary judgment or, in the alternative, for a presumption of class-wide liability. Lusardi also moved to strike Xerox’s expert report. On December 16, 1987, District Judge Alfred J. Lechner, Jr. granted Xerox’s motion to decertify the class and denied Lu-sardi’s motions as moot. In a seventy-five page opinion, the district court assessed the class in light of the “similarly situated” requirement of § 16(b) of the Fair Labor Standards Act (FLSA), codified at 29 U.S. C.A. § 216(b) (West Supp.1988) (as amended by the Portal-to-Portal Act of 1947, 29 U.S. C.A. §§ 251-262 (West 1985)). Lusardi v. Xerox Corp., 118 F.R.D. 351 (D.N.J.1987) (hereinafter Lusardi II). The district court first found that disparate employment situations among the class plaintiffs were “significant not only to plaintiffs' claims but as well to the ability of Xerox to defend against the claims.” Id. at 361. In examining Xerox’s defenses to several of the sample group members’ claims, the court concluded that “the proposed class plaintiffs are not similarly situated and that considerations of fairness, as well as, efficiency are defeated by maintenance of a class action in this case.” Id. at 363. The court reasoned:
To proceed without permitting Xerox to raise at the liability stage of trial each and every defense available to it where each potential class member is readily identifiable and must step forward in order to assert and prove an individual claim for liability or at least be the subject of a defense particular to each such plaintiff would deprive defendant of the Fifth Amendment right to due process.
App. at 667 (footnote omitted).
The court interpreted the FLSA § 16(b)’s “similarly situated” requirement to “presuppose” a common defense, giving the defendant an opportunity to effectively defend against the class allegations. It distinguished International Bhd. of Teamsters v. United States, 431 U.S. 324, 97 S.Ct. 1843, 52 L.Ed.2d 396 (1977), by explaining that in that case the union did not assert, or seek to assert, individual defenses against each class plaintiff. The district court also cited our decisions in Dillon v. Coles, 746 F.2d 998 (3d Cir.1984) and Gavalik v. Continental Can Co., 812 F.2d 834 (3d Cir.), cert. denied, — U.S. -, 108 S.Ct. 495, 98 L.Ed.2d 492 (1987) for the proposition that the liability phase of a class action is not concluded until the individual class members have demonstrated their bases for awards. Thus, the court reasoned, the defendant may assert each of its defenses at the liability stage of the trial. Because an ADEA class is formed by “opting-in,” thereby requiring each individual class member to demonstrate liability, “each individual class member must come forward in order to prove causation prior to any finding of liability to that class member and... in each instance Xerox has the possibility of raising any one of [its] several defenses,” the district court concluded that “plaintiffs cannot be deemed similarly situated.” Lusardi II, 118 F.R.D. at 375. For all of these reasons, the district court determined that the opt-in plaintiffs were not “similarly situated” and ordered the class decertified.
The district court also examined the ADEA’s filing requirements, interpreting § 626(d)(2) to require that each individual class plaintiff file an age discrimination charge with the EEOC before joining in a class action. The district court based its reading both on the plain language of the statute and on case law which refused to allow “piggybacking” when the EEOC filings did not allege classwide discrimination. The court read each of the four originally named plaintiffs’ EEOC charges as identical, with the exception of each plaintiff’s personal information. Those EEOC charges alleged a Xerox policy to eliminate persons over forty years old who were too old to be trained in other positions, and an employment practice discriminating against persons over forty as a class. The district court stated that these “references in the filings... do not suggest the charge of discrimination concerned any person other than the individual named in the filing.” Lusardi II, 118 F.R.D. at 378. It therefore concluded that Lusardi and the other named plaintiffs did not file on behalf of “others similarly situated.”
Lusardi appeals the district court’s order decertifying the class and petitions for a writ of mandamus. He argues that the order is appealable under the collateral order exception of Cohen. On the merits, Lusardi argues, inter alia, that the district court erred in finding that the opt-in plaintiffs were not “similarly situated” within § 16(b) of the FLSA and in interpreting the ADEA as requiring a timely EEOC filing by each of the potential plaintiffs in order to “opt-in” to the class action. Because we find that we lack appellate jurisdiction and that mandamus is not warranted except with respect to the requirement that each class plaintiff must have filed a timely administrative claim, we do not reach the merits of Lusardi’s other arguments.
II.
Appealability
We will first address the appealability of the district court’s order decertifying the class. “A class action determination, affirmative or negative, is not in this circuit a final order appealable under 28 U.S.C. § 1291.” Katz v. Carte Blanche Corp., 496 F.2d 747, 752 (3d Cir.), cert. denied, 419 U.S. 885, 95 S.Ct. 152, 42 L.Ed.2d 125 (1974); see also DeMasi v. Weiss, 669 F.2d 114, 119 (3d Cir.1982). The district court did not certify its order as final for purposes of appeal pursuant to Federal Rule of Civil Procedure 54(b) or as a controlling question of law pursuant to 28 U.S.C.A. § 1292(b) (West Supp.1988). See Saber v. FinanceAmerica Credit Corp., 843 F.2d 697, 701-02 (3d Cir.1988); Katz, 496 F.2d at 752-56.
In its order, the district court denied a stay of that order pending appeal. Until recently, the district court’s order might have been thought appealable under the Enelow-Ettelson doctrine. See Ettelson v. Metropolitan Life Ins. Co., 317 U.S. 188, 63 S.Ct. 163, 87 L.Ed. 176 (1942); Enelow v. New York Life Ins. Co., 293 U.S. 379, 55 S.Ct. 310, 79 L.Ed. 440 (1935). That avenue of appeal, however, was recently foreclosed by the Supreme Court’s decision in Gulfstream Aerospace Corp. v. Mayacamas Corp., — U.S. -, 108 S.Ct. 1133, 99 L.Ed.2d 296 (1988), overruling the Enelow-Ettelson doctrine. See also Delta Traffic Serv., Inc. v. Occidental Chem. Corp., 846 F.2d 911 (3d Cir.1988).
Lusardi’s only other available basis for appellate jurisdiction over the district court’s decertification order is the “collateral order” doctrine of Cohen, set out supra. However, the Supreme Court has held that class action determinations do not fall within the Cohen exception. Coopers & Lybrand v. Livesay, 437 U.S. 463, 98 S.Ct. 2454, 57 L.Ed.2d 351 (1978). In that case, plaintiffs, securities purchasers, brought a Rule 23 class action against an accounting firm for misstatements in a prospectus in violation of the Securities Act of 1933 and the Securities Exchange Act of 1934. The district court first certified and later decertified the class. The Court of Appeals held it had jurisdiction and reversed the order decertifying the class. The Supreme Court granted certiorari and held the order not appealable under 28 U.S.C. § 1291. After setting out the three prongs of Cohen’s “collateral order” exception to § 1291, the Court held that the district court’s order did not fall within that exception:
First, such an order is subject to revision in the District Court. Second, the class determination generally involves considerations that are “enmeshed in the factual and legal issues comprising the plaintiff’s cause of action.” Finally, an order denying class certification is subject to effective review after final judgment at the behest of the named plaintiff or intervening class members. For these reasons,... the collateral-order doctrine is not applicable to the kind of order involved in this case.
Coopers & Lybrand, 437 U.S. at 469, 98 S.Ct. at 2458 (footnotes and citations omitted).
We dismissed Xerox’s earlier appeal of the district court’s order conditionally certifying the class for similar reasons. See Lusardi I, 747 F.2d at 177-78. Plaintiffs argue that Lusardi I is distinguishable because it dealt with the conditional certification of a class rather than a decertification, which plaintiffs term a “final order.” A decertification order is reviewable upon appeal from a final judgment. Samuel v. University of Pittsburgh, 506 F.2d 355, 360 (3d Cir.1974). Therefore, such an order, whether based on a Rule 23 or an FLSA § 16(b) class action, fails to fall within the Cohen “collateral order” exception. The wisdom of denying appellate review of class determinations is well illustrated by this case. In opt-in class actions, with their similarities to bills of peace, permissive joinders and intervention and their accompanying tolling problems, it is of the utmost importance that the decision on class status be made promptly so that class members know whether to accept the “invitation to come in” or look out for themselves. See Z. Chafee, Some Problems of Equity, 259-61 (1950) (hereinafter Chafee). Lusardi filed his first complaint on March 8, 1983. On January 30, 1984 the district court decided to conditionally certify a class. There was an appeal and accompanying petition for mandamus. The case was transferred to a different district judge. Discovery dragged on. On December 16, 1987, the district judge decertified the class. As noted, we stayed that order. The case will now be remanded with the class status to be redetermined.
III.
Mandamus
In their petition for mandamus, Lusardi and the other individual plaintiffs assert five reasons why the writ should be granted. Before considering those reasons separately, we believe it is useful to set forth generally the principles applied in this jurisdiction in determining whether this extraordinary writ should issue, as well as those relating to the certification and maintenance of actions under FLSA § 16(b).
A.
Authority to issue mandamus is granted by 28 U.S.C.A. § 1651. It provides:
(a) The Supreme Court and all courts established by Act of Congress may issue all writs necessary or appropriate in aid of their respective jurisdictions and agreeable to the usages and principles of law.
28 U.S.C.A. § 1651(a) (West 1966).
The writ is an extraordinary use of power by an appellate court. Its use is contrary to the common law policy of avoiding piecemeal appellate review of cases pending in courts of original jurisdiction. The policy is of great importance in preserving judicial efficiency and orderly procedure. Cases which go through a trial court by fits and starts are not likely to have a reasonably prompt disposition. Halting their flow through the judicial system while awaiting appellate consideration of interim orders or decrees is, at best, disruptive. Also, use of the writ is likely to require resolution of issues which disappear or shrink to insignificance in the context of a final judgment. As stated, this case is a good example of the problems its use or solicitation creates.
Modern appellate practice includes various devices unknown to the common law when the writ was developed. They both serve to oil the somewhat arthritic joints of the strict common law rule of finality and to decrease the need for parties to rely exclusively upon the writ for relief from a court order. The lubricants include the certified interlocutory appeal, 28 U.S.C.A. § 1292(b), and the judicially developed collateral order exception of Cohen.
Accordingly, the writ is seldom issued and its use is discouraged. Nevertheless, when no other avenue is open, i.e., when a party seeking the writ has no other adequate means to attain the relief he desires and the court below has committed a clear error of law, it may issue. Cipollone v. Liggett Group, Inc., 785 F.2d 1108, 1118 (3d Cir.1986) (quoting Sporck v. Peil, 759 F.2d 312, 314 (3d Cir.1985)), cert. denied, — U.S. -, 108 S.Ct. 487, 98 L.Ed.2d 485 (1987). The clear error should at least approach the magnitude of an unauthorized exercise of judicial power, or a failure to use that power when there is a duty to do so. Will v. Calvert Fire Ins. Co., 437 U.S. 655, 661, 98 S.Ct. 2552, 2556, 57 L.Ed.2d 504 (1978); Citibank, N.A. v. Fullam, 580 F.2d 82, 86 (3d Cir.1978).
These requirements are in accord with § 1651(a). When they are met, issuance of mandamus may be necessary to preserve appellate jurisdiction. Otherwise, our ability to review an issue likely to control the availability of the relief sought would be lost. It is also “agreeable to the usages and principles of law:”
“[Traditional use of the writ in aid of appellate jurisdiction both at common law and in the federal courts has been to confine an inferior court to a lawful exercise of its prescribed jurisdiction or to compel it to exercise its authority when it is its duty to do so.”
Calvert Fire Ins. Co., 437 U.S. at 661, 98 S.Ct. at 2556 (quoting Roche v. Evaporated Milk Ass’n, 319 U.S. 21, 26, 63 S.Ct. 938, 941, 87 L.Ed. 1185 (1943)).
Still, the presence of power does not compel its exercise. Even in the presence of a clear error of law which would otherwise escape review and a showing by a party that his right to this relief is “clear and indisputable,” issuance of a writ is within our discretion. Kerr v. United States District Court, 426 U.S. 394, 403, 96 S.Ct. 2119, 2124, 48 L.Ed.2d 725 (1976). In using that discretion, judges should proceed both carefully and courageously.
B.
Special problems are present in determining whether mandamus is warranted in the context of the kind of class action before us. The availability of the class action device to Lusardi is not controlled by Federal Rule of Civil Procedure 23, but by § 16(b) of the FLSA, incorporated into the ADEA by § 626(b) of that statute. The current version of FLSA § 16(b) reads, in relevant part:
(b)... An action to recover the liability prescribed in [this subsection] may be maintained against any employer (including a public agency) in any Federal or State court of competent jurisdiction by any one or more employees for and in behalf of himself or themselves and other employees similarly situated. No employee shall be a party plaintiff to any such action unless he gives his consent in writing to become such a party and such consent is filed in the court in which such action is brought.
29 U.S.C.A. § 216(b) (West 1988).
On June 25, 1938, the date of § 16(b)’s enactment, the Federal Rules of Civil Procedure had been proposed and were pending before Congress, but had not yet become effective. One problem bedeviling the common law of class actions in this country in 1938 was the binding effect of the class action decree on absent class members. Chafee, supra, at 224-25. In the United States the application of res judicata to absent parties in class suits raised constitutional issues of due process. Compare Supreme Tribe of Ben Hur v. Cauble, 255 U.S. 356, 41 S.Ct. 338, 65 L.Ed. 673 (1921) (holding all members of beneficial society bound by state decree in class action, including citizens of the state in which federal action seeking to enforce state decree was brought, who were not parties to the state suit) and Restatement of Judgments § 86 (1942) (all members of class bound) with Hansberry v. Lee, 311 U.S. 32, 61 S.Ct. 115, 85 L.Ed. 22 (1940) (reversing Illinois Supreme Court order that decree in class action enjoining violation of racially restrictive covenants bound absent class members).
Two efforts were made in 1938 to deal with the due process problem in applying res judicata to class actions. Those efforts formalized the opt-in class. First, Congress enacted § 16(b) for the special purpose of facilitating enforcement of the FLSA. Second, and more generally, the Advisory Committee on the Federal Rules provided for notice to absent class members and included in old Rule 23, 23(a)(3)’s “spurious class.” Under both the statute and the rule, class actions in which absent members were not bound by the judgment were recognized. See Pentland v. Dravo Corp., 152 F.2d 851, 853 (3d Cir.1945). Difficulties in assigning a particular class action to one of the three categories of old Rule 23(a) led to the abandonment of the spurious class in the 1966 amendment to the rule, but the. opt-in class remains with us under § 16(b). See Fed.R.Civ.P. 23 advisory committee’s note (1966 amendment).
Because § 16(b)’s coverage has been extended to age and sex discrimination laws to facilitate their enforcement, the class action in which only members who agree to participate are bound remains an important tool for their enforcement in cases of systemic discrimination. Used properly, it reduces multiplicity of suits and offers a convenient means of settling issues common to a large number of persons whose interest is sufficiently similar. To accomplish the Congressional purpose of encouraging private enforcement of these statutes by making it convenient and inexpensive for the persons they are meant to protect, the members of the class who opt-in receive the benefit of final judgment despite the action’s non-binding effect on absent members. Considering the historical development of opt-in class actions, and the analogies drawn to bills of peace, permissive joinder and intervention, the question arises whether each member of the opt-in class must individually satisfy all timeliness requirements. The resolution of that issue depends upon the intent of Congress in enacting § 16(b) and the incorporation of that section into the ADEA. Those issues are discussed infra section IY(D).
IV.
With these general principles and background in mind, we examine Lusardi’s arguments for granting mandamus.
A.
Lusardi first argues that the district court’s December 16, 1987 order violates the doctrine of law of the case because it conflicts with the January 31, 1984 order of another judge of that court conditionally certifying the class. In support, he cites Hayman Cash Register Co. v. Sarokin, 669 F.2d 162 (3d Cir.1982), for the proposition that mandamus lies under 28 U.S.C.A. § 1651 when one district judge re-examines and reverses an order by another directing a transfer of a case. In Hayman, this court quoted with approval a statement by Justice Frankfurter that such conduct promotes “judicial unseemliness.” 669 F.2d at 166-68 (quoting Hoffman v. Blaski, 363 U.S. 335, 346-49, 80 S.Ct. 1084, 1091-93, 4 L.Ed.2d 1254 (1960) (Frankfurter, J. dissenting)). An examination of the prior order in this case disposes of that argument. It states:
7. Conditional certification of this action as a class action is without prejudice to the respective parties’ rights to move for decertification of the action as a class action or for enlargement or modification of the class definition or for modification of this Order.
App. at 182.
At a hearing on December 22, 1983 on the question of class certification, the district judge who entered the order of January 30, 1984 asked: “Can I do this conditionally?” Counsel for Lusardi responded: “Yes, your Honor. I expect this to be conditionally. Totally.” App. at 105. Thereafter, the following colloquy took place:
THE COURT: And then we’ll — you know, what that means really is conditional. If he can’t establish a broad base centralized policy, then I’m probably not going to go ahead with the case in this form. I’m not interested in creating a monster that no one can deal with, made up with a lot of individual people with specific grievances.
MR. FREUND: That’s right, your Honor.
THE COURT: No one is going to kill it any faster than I am. I mean in terms of not sticking — I’m not going to stick a thousand or 5,000 or 10,000 eases together that shouldn’t be. I wouldn’t be able to handle it.
If there wasn’t a broad-base policy here, then it is hard to believe this thing should go forward. But it is that very allegation which interests me in continuing this investigation.
App. at 108-09. We dismissed Xerox’s appeal from this order conditionally certifying the class for lack of jurisdiction. Lusardi I, 747 F.2d at 178.
Lusardi’s law of the case argument poses a conflict between the rationale of the order conditionally certifying the class and the rationale of the order decertifying it. Arguably, the earlier order made decertifi-cation dependent only on Lusardi’s failure to produce evidence of a company-wide pattern or practice of age discrimination. If so, once evidence of that pattern was produced, Xerox’s evidence of, or reliance on, disparate individual defenses would be irrelevant on the issue of whether the persons electing to opt-into the litigation were similarly situated. Accordingly, Lusardi contends that the order decertifying the class because of disparate defenses, as evidenced by the opinion in support of decerti-fication, conflicts with the order conditionally certifying the class.
The order conditionally certifying the class expressly contemplates the possibility of later decertification. When the recognized possibility of decertification is made a reality by the later order, there is no clear conflict or unwarranted re-examination. A writ of mandamus based on conflicting action by two coordinate judges should issue only on a plain conflict in their orders. Appeals do not lie and writs do not issue to reconcile ratio decidendi. They are used to vacate, reverse, affirm or modify orders. The asserted conflict between the order of conditional certification and the order of decertification does not warrant mandamus.
B.
Lusardi’s second contention is that “[t]he district court committed a clear abuse of discretion by requiring direct proof of discriminatory intent by Xerox in order for plaintiffs Lusardi to establish a prima facie case of a pattern and practice of age discrimination in this FLSA section 16(b) class action.” Plaintiffs’ Petition for Mandamus at 37. As he develops this argument, Lusardi shifts to a contention that statistical proof of the disparate impact of a reduction in force creates a pri-ma facie case entitling each member of the protected class who opts in to jury consideration of his discrimination claim. This presence of statistical proof, he contends, is a common issue of fact that makes all the opt-in claimants similarly situated within the meaning of § 16(b) of FLSA. See Distelhorst v. Day & Zimmerman, 58 F.Supp. 334, 335 (S.D.Iowa 1944) (holding any common issue of fact meets the similarly situated test of FLSA § 16(b)), appeal dismissed, 150 F.2d 541 (8th Cir.1945).
In making that argument, Lusardi relies on United States Postal Serv. Bd. of Governors v. Aikens, 460 U.S. 711, 103 S.Ct. 1478, 75 L.Ed.2d 403 (1983), as well as our recent in banc decision in Chipollini v. Spencer Gifts, Inc., 814 F.2d 893, (3d Cir.), cert. dismissed, — U.S. -, 108 S.Ct. 26, 97 L.Ed.2d 815 (1987). Those cases stand for the proposition that direct evidence of discriminatory intent is not necessary to establish a prima facie case or prove unlawful discrimination. We will assume, ar-guendo, that statistical evidence may create a prima facie case of discrimination. See Teamsters, 431 U.S. at 339, 97 S.Ct. at 1856; EEOC v. American Nat’l Bank, 652 F.2d 1176, 1188 (4th Cir.1981), cert. denied, 459 U.S. 923, 103 S.Ct. 235, 74 L.Ed.2d 186 (1982). However, the law is not clear, in this circuit or elsewhere, that the presence of statistical evidence of a disparate impact or a pattern of discrimination deprives a district court of its discretion to decide whether to certify, or continue to certify, an opt-in class under FLSA § 16(b). To say a district court has no discretion to refuse or revoke class certification in a § 16(b) systemic discrimination case whenever there is statistical evidence of disparate impact, for example, is equivalent to saying that all individuals in a protected class are “similarly situated” under FLSA § 16(b) when statistical evidence indicates a personnel policy has a disparate impact on the protected class as a whole. We do not think that legal proposition is as yet established, and is certainly not yet established as a matter of clear law.
If the district court does, in fact, require Lusardi to produce both direct proof of discrimination and appropriate statistical evidence of a disparate impact or a practice of discrimination in order to get his claim to a jury, that issue will be subject to review on appeal from a final order. We then can decide whether the conflicting statistical evidence required the district court to maintain the case as an opt-in class action simply because of the common issue which exists in all systemic discrimination cases. If those questions are properly presented on appeal from a final order and we determine that class certification is required, all opt-in members who have not chosen to proceed individually will be fully protected by reinstatement óf the action as a class action. The case would then necessarily be remanded to the district court for continuation as a class action pursuant to the provisions of FLSA § 16(b). The reinstatement of the class will at least relate back to their acceptance of what Chafee calls the “invitation to come in,” that is, to when they opted in. See Gelman v. Westinghouse Elec. Corp., 556 F.2d 699, 701 (3d Cir.1977). Accordingly, the remedy of appeal is an adequate means of relief with respect to these issues and mandamus does not lie on this ground. See Cipollone v. Liggett Group, Inc., 785 F.2d 1108, 1118 (3d Cir.1986), cert. denied, — U.S. -, 108 S.Ct. 487, 98 L.Ed.2d 485 (1987).
C.
Lusardi’s key attack on the decertification order is his contention that the district court “committed a clear abuse of discretion” in holding that Xerox’s assertion of disparate defenses to individual claims precludes an opt-in class action under FLSA § 16(b). EEOC, in its amicus brief, joins Lusardi in this contention. Translated into Cipollone terms, Lusardi and EEOC argue that it is clear legal error for a district court to consider disparate individual defenses in deciding whether an FLSA § 16(b) action can be maintained as a class action. If they are correct, a question on which we express no opinion, it is not necessary to resort to the extraordinary writ of mandamus in order to preserve our “potential appellate jurisdiction.” Calvert Fire Ins. Co., 437 U.S. at 661-62, 98 S.Ct. at 2556-57. The question of whether the statistical issue common to all persons claiming systemic discrimination makes them all “similarly situated” under FLSA § 16(b) as a matter of law, and so requires class certification, will be reviewable on appeal from a final order on Lusardi’s individual claim. Coopers & Lybrand, 439 U.S. at 469, 98 S.Ct. at 2458. If the presence of that common issue of statistical fact does not make all the opt-ins similarly situated as a matter of law, the issue of whether the district court abused its discretion in denying certification on the facts of this case can be addressed in an appeal on behalf of the class. In the face of Lusardi’s assertion and the district court’s finding that he and the other named plaintiffs are adequate class representatives, we cannot assume they will abandon the cause of the class simply because they win individual relief.
To issue mandamus because a trial judge has denied class certification based on the assertion of individualized defenses by an employer would remove the judge’s discretion over manageability of the litigation. Cf. In re School Asbestos Litigation, 789 F.2d 996, 1011 (3d Cir.) (“The potential for individualized defenses does not detract from the commonality of the questions as viewed from the standpoint of the class members, but the problem clearly poses significant case management concerns.”), cert. denied, — U.S. -, 107 S.Ct. 182, 93 L.Ed.2d 117, cert. denied, — U.S. -, 107 S.Ct. 318, 93 L.Ed.2d 291 (1986). It would also violate this circuit’s rule that the writ is not available to review a class determination, affirmative or negative

Question: What party initiated the appeal?
A. Original plaintiff
B. Original defendant
C. Federal agency representing plaintiff
D. Federal agency representing defendant
E. Intervenor
F. Not applicable
G. Not ascertained
Answer:

Answer: A