A recent decision denying certification of a securities-fraud class action underscores that plaintiffs must prove with evidence that they satisfy the requirements of Federal Rule of Civil Procedure 23, not merely allege that they do so or promise that they can.

The decision in In re Kosmos Energy Limited Securities Litigation arose from a class action filed in the Northern District of Texas by plaintiffs challenging certain statements made in connection with the defendant’s initial public offering (“IPO”). The court denied the plaintiff’s motion to certify a putative class of stock purchasers.

In its opinion, the court provided a useful overview of class-certification law, explaining that courts have moved “away from the presumptively pro-plaintiff view” of class actions that had prevailed decades ago. The court explained that “[g]oing forward, the clear directive to plaintiffs seeking class certification—in any type of case—is that they will face a rigorous analysis by the federal courts, will not be afforded favorable presumptions from the pleadings or otherwise and must be prepared to prove with facts—and by a preponderance of the evidence—their compliance with the requirements of Rule 23” (emphases added)

The court concluded that the plaintiff had failed to provide evidence establishing that it would be an adequate class representative or that common issues of law or fact would predominate over individualized ones. The plaintiff had attempted to rest in large part on allegations in the complaint and broad statements in dicta in past decisions. The court didn’t buy it.

The court first explained that “adequacy is the plaintiff’s burden to prove—not the defendant’s burden to disprove.” The court also criticized the plaintiff’s declaration attesting in impossibly vague terms that she had “reviewed” the pleadings and “supervised” her lawyers. As the court put it, “this type of generic detail is really no detail at all, for it provides naught by which to assess [the plaintiff’s] credibility, her knowledge about the underlying facts of the case, or how much of what she has stated may have been prompted by counsel. Indeed, any potential class representative in any securities case could make almost identical assertions.”

With respect to predominance, the court concluded that the plaintiffs were effectively asking for an assumption that securities class actions are certifiable. That “assumption,” the court explained, was “ill-founded.” The court also emphasized that “[w]hile Defendants offered a 107-page Expert Report demonstrating the need for individual inquiries into investor knowledge, Lead Plaintiff offered no proof from which to draw an inference that individual inquiries may not be required if the Court were to certify this putative class . . . .”

This decision is good news for businesses—and not just in the context of securities-fraud class actions. True, those suits are subject to heightened pleading requirements set forth in the Private Securities Litigation Reform Act (“PSLRA”). But the court’s denial of class certification rested on fundamental principles arising from Rule 23 itself, which applies to all class actions in federal court.