In Lindsay Transmission, LLC v. Office Depot, Inc., No. 12-0221 (E.D. Mo. Jan. 24, 2013), the plaintiff corporation brought an action under the Telephone Consumer Protection Act, complaining of the receipt of unsolicited faxes. Plaintiff proposed a class consisting of any person to whom an unsolicited fax was sent if the defendant could not provide evidence of prior authorization or an established business relationship. Defendant moved to strike class allegations and argued the class was a “fail-safe class,” which is “defined so that whether a person qualifies as a member depends on whether the person has a valid claim.” The court found such a class definition improper – the class member either wins or, by virtue of losing, is defined out of the class. The court emphasized that the class definition must define an ascertainable class. It cannot leave the individual determinations of whether class members can state claims or are subject to defenses to separate proceedings. As defined, the proposed class could not be ascertained with reference to objective criteria, and was thus improper.