concurring in part and dissenting in part:
I fully concur in the court’s affirmance of the district court’s summary judgment for United on the plaintiffs’ “disparate treatment” claims under the Age Discrimination in Employment Act and individual claims under the Americans with Disabilities Act. I must respectfully dissent, however, from the reversal of the district court’s grant of summary judgment for United on the plaintiffs’ remaining claims under Title VII and the Age Discrimination in Employment Act.1
*858I
Although the majority deploys a raft of arguments in the alternative to support its holding that the plaintiffs’ facial attack on United’s weight policy is not precluded by the judgment entered in Air Line Pilots Association, International v. United Air Lines, Inc. (“ALPA ”), 26 F.E.P. Cases 607, 1979 WL 34 (E.D.N.Y.1979), none of those arguments is compelling — indeed, some of them conflict fundamentally with preclusion doctrine, in my view.2
A
The majority’s first two arguments against granting the ALPA judgment pre-clusive effect in this litigation are that the relevant claim under Title VII of the Civil Rights Act of 1964 (“Title VII”), 42 U.S.C. § 2000e, did not “arise” until after 1979 (i.e., after that judgment was entered), supra at 850, and that “the claim is based on a different weight policy from that challenged in ALPA,” supra at 851.
As an initial matter, these two contentions seem to me to be part and parcel of the same argument. The claim did not “arise” before 1979 either because the ALPA plaintiffs did not think (or bother) to make it before then or because the distinct factual circumstances — United’s implementation of its new weight policy— did not obtain before then. If the majority’s reference to the “arising” of the plaintiffs’ claim is captured by the second possible reading, the majority’s first two arguments are logically indistinguishable.
It is plain that the first possibility cannot militate against giving the ALPA judgment preclusive effect, notwithstanding the decontextualized dictum from International Technologies Consultants, Inc. v. Pilkington, PLC, 137 F.3d 1382, 1388 (9th Cir.1998), that the majority quotes for the overstated proposition that prior favorable judgments do not “preclude claims based on events occurring [therejafter.” See supra at 851 (“ ‘By winning the first action, the defendants “did not acquire immunity in perpetuity from the antitrust laws.” ’ ”). As the very purpose of preclusion doctrine “is to protect a defendant from being worn down by a plaintiff who sues him over and over again for the same allegedly wrongful conduct,” Marrese v. American Acad of Orthopaedic Surgeons, 726 F.2d 1150, 1152 (7th Cir.1984), rev’d on other grounds, 470 U.S. 373, 105 S.Ct. 1327, 84 L.Ed.2d 274 (1985), someone who has once successfully defended his allegedly obnoxious behavior in court is indeed presumptively immune from suit thereon (by the same parties) though he should persist in his offensive behavior thereafter. Cf. Go-Video, Inc. v. Matsushita Elec. Indus. Co. (In re Dual-Deck Video Cassette Recorder Antitrust Litig.), 11 F.3d 1460, 1464 (9th Cir.1993) (giving prior judgment preclusive effect because the subsequent claim appeared to rely on the misplaced theory “that every day is a new day, so doing the same thing today as yesterday is distinct from what was done yesterday.”).
It is conceivable, of course, that United’s new weight policy might avoid the preclu-sive effect of the ALPA judgment even though the mere passage of time could not. “Material operative facts occurring after the decision of an action with respect to the same subject matter may in themselves ... comprise a transaction which may be made the basis of a second action not precluded by the first.” Restatement 2d of Judgments § 24 cmt. a; see Costant*859ini v. Trans World Airlines, 681 F.2d 1199, 1202 (9th Cir.1982) (noting that “whether the two suits arise out of the same transactional nucleus of facts” is “the most important” criterion in determining whether the judgment in an earlier lawsuit precludes litigation of a second). The majority summarily concludes that United’s new weight policy is in fact a distinct transaction because it was “part of the post-judgment settlement” reached after ALFA. Like the district court, I think it plain that an across-the-board increase in maximum permissible weights and relaxed standards for older flight attendants does not amount to a “[m]aterial operative fact[ ]” with respect to an allegation that those maxima are sexually discriminatory. In order for uniform, absolute increases— which is essentially all that is “new” on the face of United’s posN1979 weight policy— to be relevant to a discrimination claim, the margin of the increase itself must be more or less accommodating to one gender than another. Such a claim has not been made in the course of this litigation and is not credible on its face. The lockstep increases in maximum permissible weights, in short, are no more material to the plaintiffs’ cause of action than the possibility that the new policy was printed and circulated on a different color of paper.
The fact that the plaintiffs’ Title VII claims in this case arise from United’s new weight policy rather than its predecessor is not material to a claim of sex discrimination because the new policy does not differ from the old one in any way that is itself material to the plaintiffs’ claim. Thus the fact that the policy was changed after the ALP A judgment cannot alone defeat that judgment’s preclusive effect. Cf. EEOC v. American Airlines, Inc., 48 F.3d 164, 169 (5th Cir.1995) (“It is not enough to avoid the preclusive effect of the prior determination ... to show merely a change in facts: a change must have occurred in facts that ... were of controlling significance.”). To hold otherwise, as the court does today, cabins preclusion doctrine so narrowly as to render it useless, for a plaintiff hoping to evade it might do so simply by emphasizing irrelevant distinctions in his pleadings.3
B
The majority’s third argument against granting preclusive effect to the judgment *860entered in ALPA is that the procedural protections for absent class members in that litigation were insufficient to bar the individual claims of those absent class members for monetary relief. In particular, the majority notes that the ALPA court certified the plaintiff class in that case under Fed.R.Civ.P. 23(b)(2), which applies to actions predominantly for declaratory and injunctive relief and does not require the same level of procedural protections for absent class members that a “damages” action brought by a class certified under Fed.R.Civ.P. 23(b)(3) has. See supra at 851. In a class action under Rule 23(b)(3), “the court [must] direct to the members of the class the best notice practicable under the circumstances, including individual notice to all members who can be identified through reasonable effort,” and this notice must indicate that members of the class may opt out of the litigation to avoid being bound by its result. Fed.R.Civ.P. 23(c)(2); see Eisen v. Carlisle & Jacquelin, 417 U.S. 156, 173, 94 S.Ct. 2140, 40 L.Ed.2d 732 (1974). The Supreme Court has declared that the protections mandated for classes certified under Rule 23(b)(3) are “an unambiguous requirement of Rule 23” in order “to insure that the judgment ... w[ill] bind all class members who did not request exclusion from the suit.” Id. at 176, 94 S.Ct. 2140. From the Court’s observation, the majority apparently infers that only judgments relating to classes certified under Rule 23(b)(3) can have preclusive effect — at least with respect to claims for damages. There are two problems with the majority’s inference.
The first problem is that the inference is logically untenable and manifestly unfounded. Strictly as a matter of logic, the mere fact that the critical notice and opt-out protections are mandatory for classes certified under Rule 23(b)(3) does not mean that the same protections were unavailable to a class certified under Rule 23(b)(2). Indeed, four years before it entered judgment in ALPA, the Federal District Court for the Eastern District of New York had held that protections entailed by Rule 23(b)(3) certification should be extended to classes certified under Rule 23(b)(2) when, as in the ALPA litigation, the plaintiffs seek significant monetary as well as equitable relief. See Gates v. Dalton, 67 F.R.D. 621, 632-33 (E.D.N.Y.1975) (holding that it was immaterial whether the plaintiff class was certified under Rule 23(b)(2) or Rule 23(b)(3), because, “in view of the reimbursement claim, notice to the class and an opportunity to ‘opt-out’ must be provided in any event. That, as noted, is the only real practical difference between the two designations.... ”). We and other circuits have also recognized that a judgment entered against a class certified under Rule 23(b)(2) may satisfy the demands of due process and bind the members of that class as though it had been certified under Rule 23(b)(3) and lost “a class action suit for money damages.” Crawford v. Honig, 37 F.3d 485, 487 n. 2 (9th Cir.1994) (noting that the case “was a class action for injunctive relief certified under Fed.R.Civ.P. 23(b)(2), which does not require notice or permit members to opt out, although a court in its discretion may provide for an opt-out or notice.”); see Fontana v. Elrod, 826 F.2d 729, 732 (7th Cir.1987) (acknowledging that, “when monetary damages are sought in a(b)(2) class action, ‘due process does require notice before the individual monetary claims of absent class members may be barred.’ ”); Johnson v. General Motors Corp., 598 F.2d 432, 437 (5th Cir.1979) (“[W]e have previously suggested that when both monetary and injunctive relief are sought in an action certified under Rule 23(b)(2), notice may be mandatory if absent class members are to be bound.”).
It is of course true that the members of the plaintiff class in this case may not have enjoyed adequate protections as members of the class certified under Rule 23(b)(2) in ALPA, notwithstanding the fact that the ALPA court could very well have extended *861such protections to them.4 The fact that the plaintiffs might have been deprived of their due process rights to notice and the opportunity to opt-out, however, cannot bar the normal preclusive effect of the judgment entered in ALPA. This is the second problem with the majority’s position. We are not in the habit of presuming violations of due process, especially when, as here, the parties supposedly suffering such a violation have never so much as alleged the fact thereof. See, e.g., Park v. California, 202 F.3d 1146, 1154 (9th Cir.2000) (rejecting a habeas petitioner’s due process claim because he “failed to fulfill his burden adequately to allege and demonstrate ... a violation of due process” despite having both specified the trial court’s error and cited “to the Fifth, Ninth, and Fourteenth Amendments”); Howlett v. Salish and Kootenai Tribes of the Flathead Reservation, 529 F.2d 238, 240 (9th Cir.1976) (noting that the plaintiffs bore the burden of demonstrating a violation of due process). Hence, even if it were within the power of this court to establish independently that the ALPA court did not require adequate notice to the members of the plaintiff class in that litigation, the plaintiffs here cannot benefit from this discovery in light of their failure to carry the burden of demonstrating (or even alleging) as much themselves.
C
The majority finally notes that the judgment entered in ALPA cannot have pre-clusive effect because the named plaintiffs in ALPA settled their claims against United with reinstatement and an award of back pay rather than appealing the ALPA court’s adverse judgment, thus proving that the named plaintiffs were insufficiently representative of the absent class members who had not yet been harmed by the weight policy.5 See supra at 852-53 (“The class representatives in ALPA failed to appeal the district court’s decision that United’s weight policy did not discriminate on the basis of sex.”). The district court in this case held that the plaintiff class in ALPA included, as the ALPA court had indicated, all former, present, and future flight attendants at United and cited our decision in NAACP v. Los Angeles Unified School District, 750 F.2d 731, 741 (9th Cir.1984), for the proposition that class actions may bind even future members of the class. The majority declares NAACP inapplicable, because “the plaintiffs [in that case] did not assert that they had been inadequately represented by the class representatives in the earlier action.” Supra at 852 n. 6.
The problem with the majority’s handy point is that the plaintiffs in this case have *862also failed to assert that they were inadequately represented. To the extent that the majority infers the critical allegation from arguments made by the plaintiffs here, the majority ignores our previous admonition that “we will not second-guess a prior decision that counsel adequately represented a class” and our recognition that the burden is squarely on the plaintiffs to “present facts which indicate a lack of adequate representation.” Brown v. Ticor Title Ins. Co., 982 F.2d 386, 390-91 (9th Cir.1992). The plaintiffs have simply waived the “inadequate representation” argument here, and thus it too cannot strip the judgment in ALPA of its preclusive effect.
D
For the foregoing reasons, I dissent from the majority’s refusal to acknowledge that the ALPA judgment precludes the plaintiffs’ facial attack of United’s weight policy as unlawful sex discrimination under Title VIL I thus believe the majority errs in reaching the merits of the complex Title VII issue. I would only note here that the majority’s purported grant of summary judgment for the plaintiffs is unsupportable. It relies on a “finding” — made for the first time here and on the basis of figures for the population at large when the plaintiff class is hardly drawn therefrom — that the evidence establishes that United’s weight program is more burdensome for female flight attendants than male flight attendants. The majority’s conclusion presses the envelope too far. Cf. Gerdom v. Continental Airlines, Inc., 692 F.2d 602, 608 (9th Cir.1982) (Noting that “[t]he general principle is that the plaintiff has the initial burden of offering evidence which is sufficient to create an inference of intentional discrimination” and holding that evidence that a weight limit was applied only to females was sufficient therefor (emphasis added)).6
II
While I concur in the majority’s affir-mance of the district court’s summary judgment for United on the plaintiffs’ claims under the Age Discrimination in Employment Act, (“ADEA”), 29 U.S.C. §§ 621-634, insofar as those claims rest on a “disparate treatment” theory, I must dissent from the court’s reversal of the district court’s summary judgment insofar as the plaintiffs’ claims rests on a “disparate impact” theory. Quite simply, the plaintiffs have waived this issue on appeal by failing to offer any argument whatsoever against the district court’s decision.
There is no room for doubt that the district court granted summary judgment for United on the plaintiffs’ disparate impact claims because it concluded that such claims are not cognizable under the ADEA after the Supreme Court’s decision in Hazen Paper Co. v. Biggins, 507 U.S. 604, 113 S.Ct. 1701, 123 L.Ed.2d 338 (1993). In reversing the district court, the majority contends that we have “squarely decided” since Hazen was handed down that a disparate impact claim is, in fact, cognizable in an ADEA case. Supra at 856. We have “squarely decided” this issue, however, only in the context of a case that is now a legal nullity. See Arnett v. California Public Employees Retirement System, 179 F.3d 690, 697 (9th Cir.1999), vacated, — - U.S. -, 120 S.Ct. 930, 145 L.Ed.2d 807 (2000). The majority makes much of the fact that Arnett was vacated “on other grounds,” see supra at 856 (“The Eleventh Amendment issue [on the basis of which the Supreme Court appears to have vacated Arnett ] is irrelevant to a case[ ] such as this one ....”), but the majority’s distinction does not alter the fact that Arnett is utterly devoid of legal force. See, e.g., O’Connor v. Donaldson, 422 U.S. 563, 577 n. 12, 95 S.Ct. 2486, 45 L.Ed.2d 396 (1975) (“Of necessity our decision vacating the judgment of the Court of Appeals deprives *863that court’s opinion of precedential effect....”); United States v. Munsingwear, Inc., 340 U.S. 36, 39, 71 S.Ct. 104, 95 L.Ed. 36 (1950) (noting that, when a decision is vacated, the path has been cleared “for future relitigation of the issues”). Indeed, we have rebuked litigants for attempting to resurrect vacated decisions on precisely the same logic. See Durning v. Citibank, N.A., 950 F.2d 1419, 1424 n. 2 (9th Cir.1991) (“Although the Authority contends that the decision was Vacated on other grounds,’ we find that contention curious. A decision may be reversed on other grounds, but a decision that has been vacated has no precedential authority whatsoever.”). I would require more than a citation to our defunct decision in Arnett before endorsing the conclusion that the district court erred.
That citation, however, is all there is on the issue. The only argument offered by the plaintiffs in opposition to the district court’s summary judgment for United on their ADEA claims has nothing at all to do with the appropriateness of disparate impact theories and is instead limited to the all-but-conclusory statement that “the evidence establishes a genuine issue of intentional age discrimination.” In addition to being entirely beside the point, the plaintiffs’ “argument” is wholly insubstantial. Even with descriptions of and citations to a few items in the record to support their characterization of the evidence, the plaintiffs manage in the course of more than a hundred pages of briefing to fill less than two with their arguments relating to the ADEA.7
I think it somewhat curious to hold, solely on the strength of a perfunctory observation, see supra at 856 (“We see no reason to depart from our conclusion in Arnett .... ”), that the district court erred in concluding that a disparate impact claim under the ADEA does not survive Hazen. To do so without any relevant briefing on the issue is worse yet. Because the plaintiffs have manifestly waived their ADEA claims on appeal, I would affirm the district court’s summary judgment for United on those claims.
Ill
Because I cannot agree with the court’s reversal of the summary judgment for United, I must also disagree with the reversal of the district court’s decertification of the class and denial of plaintiffs’ application for costs.
A
The district court’s failure to require notice of the decertification under Fed. R.Civ.P. 23(d)(2) was not an abuse of discretion, because obvious practical considerations militated strongly against requiring notice here. See Bauman v. United States District Court, 557 F.2d 650, 658 (9th Cir.1977) (reviewing requirement of notice pursuant to Fed.R.Civ.P. 23(d)(2) for an abuse of discretion).
First, United had discontinued its weight program four years before the de-certification of the class. The simple staleness of the class promised to render the typical unnamed member relatively difficult to locate.
Second, the number of individuals requiring notice would have been disproportionate to the benefits derived from notice. This is particularly true because the supposed benefit from the notice was that members of the class with individual claims were to be informed that their claims were tolled during the pendency of the class action and the claims thus tolled were exactly those that the court had already disposed of. See Crown Cork & Seal Co. v. Parker, 462 U.S. 345, 103 S.Ct. *8642392, 76 L.Ed.2d 628 (holding only that claims identical to those advanced in the putative class action are tolled during the pendency of the class certification).
B
I respectfully disagree as well with the court’s reversal of the district court’s denial of the plaintiffs’ application for costs, because the fact that the district court properly found the plaintiffs’ claims to be meritless rendered the plaintiffs’ request of an award entirely frivolous. Cf. National Information Servs., Inc. v. TRW, Inc., 51 F.3d 1470, 1471 (9th Cir.1995) (noting that the “loser bears th[e] burden” of overcoming a presumption that costs will be awarded to the prevailing party in civil litigation under Fed.R.Civ.P. 54(d)).
IV
I would affirm the district court’s grant of summary judgment for United on the plaintiffs’ Title VII, ADEA, and FEHA claims. Because the majority declines to do so on the strength of dubious arguments never made by the plaintiffs and authority lacking precedential force of any sort, I dissent from that part of the court’s disposition. Moreover, because the district court correctly granted summary judgment for United, I dissent from the reversal of the district court’s order decer-tifying the class and denying the plaintiffs’ application for costs.
It may seem inappropriate in this day and age to have seemingly arbitrary weight limitations for employees (a proposition with which United seems no longer to disagree), but our anti-discrimination statutes and law of civil procedure rest on policies more diverse than the eradication of business practices that strike us as distasteful or unfair. Those policies include protecting to the extent practicable the flexibility of private enterprise to respond to the demands of the market and protecting individuals from endlessly rehearsing (at potentially crippling expense) them defenses to allegations of unlawful conduct. In order to vindicate these other policies, the courts and Congress have drawn lines limiting what conduct is actionable and under what circumstances an employer may be called upon to defend his conduct. Because the majority ignores those lines, many of them well established, I concur in the court’s opinion only in part and dissent as to the remainder.
. I shall not separately address the plaintiffs' claims under the California Fair Employment and Housing Act ("FEHA”), Cal. Gov't Code §§ 12900-12996, but would affirm the district *858court’s judgment thereon for the reasons that follow.
. The majority suggests that the issue is whether the "post-judgment settlement,” as opposed to the actual district court judgment in ALPA, precludes these claims. See supra at 852 (rejecting United’s argument "to the degree that [it] seeks to rely on the post-judgment settlement in ALPA " because the settlement was not incorporated into the district court's judgment and did not protect the interests of absent class members). The post-judgment settlement is not relevant to the preclusion issue here. It is undisputed that the district court tendered a final judgment in ALPA, and it is the preclusive effect of that judgment that is before us.
. The plaintiffs take some pains to argue that this lawsuit cannot be barred by "claim preclusion,” as the district court held, as distinct from "issue preclusion.” Even if that were so, "we may affirm the district court’s decision based on any reason finding support in the record,” Welch v. Fritz, 909 F.2d 1330, 1330 (9th Cir.1990), and it is apparent that "issue preclusion” would suffice to preclude the present lawsuit. This is so notwithstanding the plaintiffs' attempt to distinguish the judgment in ALFA as being limited to a disparate impact theory rather than the disparate treatment theory that is at issue in this case. It is an exercise in fruitless abstractions to hypothesize that one could recover under a disparate treatment theory relying on evidence of a pattern or practice after failing to recover under a disparate impact theory. Cf. Watson v. Fort Worth Bank and Trust, 487 U.S. 977, 108 S.Ct. 2777, 101 L.Ed.2d 827 (1988).
The distinguishing features of the factual issues that typically dominate in disparate impact cases do not imply that the ultimate legal issue is different than in cases where disparate treatment analysis is used. Nor do we think it is appropriate to hold a defendant liable for unintentional discrimination on the basis of less evidence than is required to prove intentional discrimination. Rather, the necessary premise of the disparate impact approach is that some employment practices, adopted without a deliberately discriminatory motive, may in operation be functionally equivalent to intentional discrimination.
Id. at 987, 108 S.Ct. 2777 (citation omitted).
Furthermore, plaintiffs' suggestion that the judgment in ALFA disposed of only a disparate impact claim and not a disparate treatment claim is unsupported by anything but a citation to United’s statement that "Judge Pratt conducted what was indisputably a disparate impact analysis.” Judge Pratt may well have recognized that conducting a disparate impact analysis on the type of facial challenge there at issue disposed of any disparate treatment claim as well. This recognition would explain the plaintiff’s apparent contention in this case that Judge Pratt did not effectively distinguish between disparate impact and disparate treatment claims.
. It bears noting at this juncture that whether these protections were appropriately extended does not depend on the experience of any particular member of the class, because the preclusive effect of a class action depends upon the adequacy of the entire notice scheme and not upon a determination of whether the member of the class to be precluded actually received notice. See, e.g., Fontana, 826 F.2d at 732 (" '[A]n absent class member will be bound by any judgment that is entered if appropriate notice is given, even though that individual never actually received notice.’ ”)(quoting 7B Charles Alan Wright, Arthur R. Miller, & Mary Kay Kane, Federal Practice and Procedure § 1789, at 253 (2d ed. 1986)).
. The majority also notes that the preclusive effect of the judgment in ALPA cannot be inferred from the fact that the new weight program was the result of a settlement between United and the plaintiff class in ALPA. See supra at 852 ("Fourth, to the degree that United seeks to rely on the post-judgment settlement in ALPA, we need only point out that the settlement is not incorporated into a judgment and therefore cannot have preclu-sive effect.”). I see no need to address the validity of the majority's observation, for it is irrelevant that United's new weight program was the result of a settlement between the ALPA parties except insofar as it clearly establishes that the changes in United’s weight policy could not possibly provide a distinct basis for suit (as those changes were merely concessions sought by the plaintiff class). As the changes to the weight program were immaterial to a Title VII claim on their face, the fact that they were the result of a settlement is neither here nor there.
. As I would affirm the district court's summary judgment on the class claim under Title VII, I would also affirm the district court's summary judgment on individual claims.
. If there were any lingering skepticism that the plaintiffs have abandoned their disparate impact claims under the ADEA, both the fact that the plaintiffs did not take exception in their reply brief to United's statement to this effect and the fact that the plaintiffs failed to alert us to this court's purportedly disposi-tive — and decidedly helpful — decision in Ar-nett, see Fed. R.App. P. 28(j), should put such skepticism to rest.