A Customer Filed a Class Action Against My Missouri Business

That is the most important thing to understand. The dramatic damages figure in the complaint assumes certification. Knock out certification, and the case usually shrinks back to a single customer's modest claim. So the goal from day one is to act calmly, preserve everything, and build toward defeating certification — while checking whether a contract clause or a federal statute can resolve the whole thing early.

First, understand that one plaintiff is not a class

The complaint names a person — sometimes called the "class representative" — who claims that what happened to them happened to many others. But until a court rules on a motion for class certification, that plaintiff speaks only for themselves. The other customers are not yet parties, and the court has not found that their situations are alike enough to be tried together.

• The case has two phases. First the parties litigate whether a class can be certified; only if it is do you face true classwide exposure.
• Certification is not about who is right. It is about whether the dispute can fairly be resolved as a group. You can lose the certification fight on the merits later and still win it now by showing the claims are too individual to group.
• Most of the leverage is here. A denial of certification frequently ends the practical threat, because pursuing one person's small claim alone rarely makes economic sense for the other side.

The certification test under Missouri Rule 52.08

In Missouri state court, class actions proceed under Missouri Supreme Court Rule 52.08, which closely mirrors Federal Rule of Civil Procedure 23. To certify a class, the plaintiff must first clear four threshold requirements:

• Numerosity. The group is so large that suing individually is impractical.
• Commonality. There are questions of law or fact common to the group.
• Typicality. The named plaintiff's claim is typical of the group's claims.
• Adequacy. The named plaintiff and their counsel will fairly and adequately protect the group's interests.

For a class seeking money damages, the plaintiff must also satisfy two more demanding requirements: that common questions predominate over individual ones, and that a class action is the superior way to resolve the dispute. These last two are where most damages classes succeed or fail.

Why "predominance" is often your strongest defense

Predominance asks whether the case can really be tried as one. If proving each customer's claim would require its own mini-trial, common questions do not predominate, and certification should fail. That is frequently the case, and it is your most powerful anti-certification argument.

This bites especially hard in a Missouri Merchandising Practices Act claim. The MMPA's private remedy lives in RSMo § 407.025, and the 2020 reforms (Senate Bill 591) reshaped it. A private plaintiff now generally must prove they acted as a reasonable consumer, that the practice would cause a reasonable person to enter the transaction, and — critically — an ascertainable loss established through individualized proof, not a group-wide formula.

• Reliance and loss vary by customer. Each person may have seen different ads, relied on different things, and suffered a different loss — or none at all.
• Individualized proof defeats grouping. When the statute itself demands customer-by-customer evidence of reliance and loss, it becomes far harder to show that common questions predominate.
• The 2020 reforms were built for this fight. SB 591 deliberately tightened class certification toward federal-style rigor and individualized proof, which is exactly the leverage a defendant business now has.

Two early defenses that can end the case fast

Before settling into a long certification fight, have counsel check whether either of these can short-circuit the whole thing.

• An arbitration clause with a class-action waiver. Look at the contract your customers signed — terms of service, a purchase agreement, an account application. If it contains an arbitration clause with a class-action waiver, the Federal Arbitration Act (9 U.S.C. § 1 et seq.) generally enforces it. That can compel the named plaintiff into individual arbitration and knock the dispute out of court entirely, eliminating the class threat.
• Removal to federal court under CAFA. The Class Action Fairness Act (28 U.S.C. § 1332(d)) lets you remove many class actions from state to federal court when the proposed class is large enough and the amount in controversy and minimal-diversity thresholds are met. Federal court applies Rule 23 directly and is often a more favorable forum for the certification fight. Removal has a tight deadline, so this must be assessed immediately.

Neither is guaranteed — both turn on your specific contracts and the numbers — but either can change the entire trajectory of the case, so they are the first things to evaluate.

What to do in the first days

The early steps are about protecting yourself and your options. Do them in parallel, with counsel, right away.

• Issue a litigation hold immediately. The moment you are sued, you have a duty to preserve evidence. Send a written hold instructing your team to stop deleting emails, records, and data that could relate to the claim. Destroying records — even routinely — can expose you to sanctions.
• Preserve all records. Pull and protect the relevant contracts, customer communications, ads, and transaction data. These same records often supply the individualized facts that defeat predominance.
• Notify your insurer today. Many liability policies cover defense costs and sometimes settlement. Tender the claim promptly; late notice can jeopardize coverage.
• Calendar every deadline. The deadline to answer or move, and the CAFA removal window, are unforgiving. Miss one and you lose options regardless of the merits.
• Have counsel check your customer agreements. Specifically for an arbitration/class-waiver clause and to assess CAFA removal.
• Build the anti-certification strategy. Frame the case early around the lack of predominance and the individualized proof the claims require.
• Weigh settlement exposure carefully. A classwide settlement can be efficient, but it also defines and binds the whole group; size it against the realistic odds of certification, not the headline number in the complaint.

Frequently Asked Questions