In Comcast, an antitrust case, a district court certified a 23(b)(3) class on the unusual premise that predominance of common questions over individual questions can only be shown if damages could be proven on a classwide basis. It held that one of the plaintiffs' four theories of antitrust impact could prove damages on a classwide basis, held that a particular damages model was up to that task, and certified the class, limiting proof of damages to the one theory. The plaintiffs were happy to get a class certified at all, and therefore didn't appeal the dubious aspects, from their perspective, of the certification order. Comcast did appeal, and the Third Circuit affirmed. The Court, taking the case on the premise that classwide proof of damages was needed for 23(b)(3) certification, and on the factual background of a certification order that made no attempt to bifurcate liability and damages, held that because the damages model really couldn't measure damages on a classwide basis, individual damages questions predominated over common questions. A Ginsburg/Breyer joint dissent, joined by Sotomayor and Kagan, argued that the Court had taken the case on odd premises, contrary to settled class-action law, and that the Court's assumption of those premises broke no new ground on predominance.
Comcast caused a great deal of confusion, with many courts, including some circuits, agreeing with the dissent that Comcast changed nothing, and others taking Comcast literally when it said that the plaintiffs "could not show 23(b)(3) predominance . . . [because] [q]uestions of individual damage calculations will inevitably overwhelm questions common to the class," and concluding that any class with time-consuming individual damage issues couldn't satisfy 23(b)(3). (For a very capable and more nuanced account of post-Comcast confusion, see this excellent Chicago Law Review student comment.) While Comcast's more careful readers generally agreed with the dissent - after all, the Comcast Court was pretty explicit about having taken the case on the premise that the class-defense bar wanted to take for a holding - it was difficult to escape the impression that Comcast's author (Justice Scalia), at least, agreed with that premise. Otherwise, the Court's emphatic statements about the plaintiffs' inability to show predominance given the overwhelming individual damage calculations would probably have been couched in terms of concessions and unpreserved arguments. And, given the collapse of the question presented (a Daubert-at-class-certification question that Comcast turned out to have failed to preserve), the Court probably wouldn't have gone ahead to decide a different issue in the petitioner's favor if there wasn't some zeal among the majority for its holding.
Tyson inters the broad reading of Comcast, which is to say, the only meaningful reading of Comcast (apart from the interesting antitrust-specific reading offered in the comment linked to above). Writing on predominance, Justice Kennedy says this for the Court, quoting from several treatises:
The predominance inquiry “asks whether the common, aggregation-enabling, issues in the case are more prevalent or important than the non-common, aggregation-defeating, individual issues.” When “one or more of the central issues in the action are common to the class and can be said to predominate, the action may be considered proper under Rule 23(b)(3) even though other important matters will have to be tried separately, such as damages or some affirmative defenses peculiar to some individual class members.”And so goes the broad reading of Comcast, in an opinion that doesn't even bother to mention Comcast. Individual damages questions are not an obstacle to 23(b)(3) certification. In dissent, Justice Thomas points out, for only himself and Justice Alito, that this is contrary to what the Court recently "held" in Comcast, quoting the passage of Comcast quoted above while not grappling with the fact that the substance of what he quotes was uncontested by the Comcast plaintiffs and not briefed or argued in Comcast. For good measure, he claims that the Court's "treatise citations" were the same ones relied on by the Comcast dissent to argue the Court's assumed premise was wrong. (The majority has no response to this, or to any of Justice Thomas's dissent, as is usually the case when Justice Kennedy writes for the Court.) It would be very funny if it were true, but as it turns out, the Court cited the same unexceptionable treatises as the Comcast dissent (Newberg on Class Actions, Wright and Miller), as the Court often does when writing on Rule 23, but not the same sections.
Finally, class-action buffs who've read the late, great Richard Nagareda's brilliant and influential "Class Certification in the Age of Aggregate Proof" in its entirety,* and not just the anti-certification snippets that Wal-Mart v. Dukes made justly famous, will be very happy to see this elegant line from Nagareda, which could have been intended by Nagareda as a corrective to some of the broad misreadings of Wal-Mart had it been written after Wal-Mart was decided (and clearly is intended that way by the Court):
When, as here, “the concern about the proposed class is not that it exhibits some fatal dissimilarity but, rather, a fatal similarity—[an alleged] failure of proof as to an element of the plaintiffs' cause of action—courts should engage that question as a matter of summary judgment, not class certification.”* See also his masterful "Common Answers for Class Certification," a pithier article covering much of the same ground that features a remarkably prescient take on Wal-Mart.