The Rule 23 Subcommittee Should Have Taken on Ascertainability

Ascertainability—that is, the question of whether you can identify who is in a proposed class from the definition—occupies a distinctive place in class action doctrine. It has long been considered a vital case management tool. See Abbott v. Lockheed Martin Corp., 725 F.3d 803, 810 (7th Cir. 2013) (Wood, J.) ("The class definition is a tool of case management. It settles the question who the adversaries are, and so it enables the defendant to gauge the extent of its exposure to liability and it alerts excluded parties to consider whether they need to undertake separate actions in order to protect their rights."). While there is no formal mention of the ascertainability requirement in Rule 23, most court consider it an "essential" prerequisite for a class action. See Marcus v. BMW of N. Am., LLC, 687 F.3d 583, 592–93 (3d Cir. 2012) ("[A]n essential prerequisite of a class action, at least with respect to actions under Rule 23(b)(3)), is that the class must be currently and readily ascertainable based on objective criteria."). And many treat it as a threshold inquiry before embarking on the formal Rule 23. See In re Fosamax Prods. Liab. Litig., 248 F.R.D. 389, 395 (S.D.N.Y. 2008) ("Rule 23 contains the additional, implicit requirement that an ascertainable class exists and has been properly defined."). In fact, the leading treatise on civil procedure addresses the question before it begins its discussion of the specific requirements of Rule 23(a). See 7A Charles Alan Wright et al., Federal Practice and Procedure § 1760, at 142–47 (3d ed. 2005) ("Further, the class must not be defined so broadly that it encompasses individuals who have little connection with the claim being litigated; rather it must be restricted to individuals who are raising the same claims or defenses as the representative. The class definition also cannot be too amorphous.") (footnotes omitted).