In the case of Mathias v. WorldCom Technologies, 2001, plaintiffs filed a class action lawsuit against WorldCom Technologies for alleged violations of the Telephone Consumer Protection Act (TCPA). The TCPA prohibits unsolicited fax advertisements and provides statutory damages for each violation. The main issue in this case was whether or not these damages could be aggregated to meet the $75,000 amount-in-controversy requirement for federal diversity jurisdiction. The U.S. Supreme Court held that they could not be aggregated because claims by multiple plaintiffs cannot generally be combined to satisfy this requirement unless they are seeking "to enforce a single title or right in which they have a common and undivided interest." Since each plaintiff's claim arose from separate occurrences (i.e., receiving different faxes), their interests were distinct and independent rather than common and undivided.

The dissenting opinion in the case of Mathias v. WorldCom Technologies, 2001 argued that the majority's ruling was inconsistent with previous decisions and interpretations of federal law. The dissenters believed that the Federal Communications Act did not preempt state-law claims related to billing disputes between telecommunications companies and their customers. They contended that allowing such preemption would undermine states' rights to regulate consumer protection within their borders, which could lead to a lack of accountability for corporations like WorldCom. Furthermore, they disagreed with the majority's interpretation of "rates" under federal law, arguing it should not include late fees or other charges beyond basic service rates. This broader interpretation by the majority could potentially shield telecoms from liability for unfair business practices at a state level.