What is Class Certification? (And Why It Matters to You)
By Timo Bakker · July 3, 2026 · 5 min read
Class certification is the courtroom milestone that decides whether a case can proceed as a class action or has to be broken back into individual lawsuits. Most class actions live or die here. Here is what it means for you.
The four legal requirements (Rule 23)
Federal Rule of Civil Procedure 23 requires the court to find:
- Numerosity: the class has enough members that individual joinder is impractical (usually 40+ people).
- Commonality: the class members share common legal or factual questions.
- Typicality: the named plaintiff's claims are typical of the class.
- Adequacy: the named plaintiff and class counsel will adequately represent the class.
Plus one of: (b)(1) risk of inconsistent judgments, (b)(2) declaratory relief, or (b)(3) common issues predominate over individual ones (the most common consumer class action ground).
Why certification is where most cases die
Corporate defendants spend the most legal effort here. If they can convince the judge that the class members' situations vary too much (breaks commonality/typicality), the case gets decertified — and the plaintiffs are back to individual lawsuits, which almost never make economic sense at consumer harm levels.
Once certified, what happens
The court sends notice to all class members. If you are a class member, you have three options: file a claim eventually (when the settlement comes), opt out, or object (if you think the eventual settlement is bad). See what happens if you do nothing for the fourth (default) option.