Last week, in United States v. U.S. Cellular Corp., No. 23-7041 (D.C. Cir. 2025), the D.C. Circuit side-stepped the applicability of the “public disclosure bar” when it revived two whistleblower suits under the False Claims Act (FCA). The court’s opinion offers important new guidance to entities and individuals considering voluntary disclosure: even where a company discloses prior conduct, it may still face FCA liability if a whistleblower can “materially add” to the previously-disclosed facts.

The FCA prohibits the submission of false or fraudulent claims for payment to the Government and provides for treble compensatory damages and statutory penalties. It is among the Government’s most popular enforcement tools, particularly because it provides that private individuals or entities (relators) can bring qui tam actions on behalf of the Government and share in any recovery. Claims filed by relators remain under seal to provide the United States with an opportunity to investigate the claims and determine whether to intervene.

One defense to qui tam actions is the public-disclosure bar, which prohibits FCA claims based on fraud that has already been publicly disclosed. There is, however, an exception to this bar for a relator who is an original source of the information. A relator is an original source if they:

1. voluntarily disclosed to the Government the information on which the claim is based, or
2. have knowledge that is independent of and materially adds to the publicly-disclosed allegations.

Courts have wrestled with what information a relator must provide in order to materially add to publicly disclosed allegations.

The “original source” exception was central to the D.C. Circuit’s decision in U.S. Cellular Corp. There, two relators brought a lawsuit under the FCA, alleging that U.S. Cellular concealed their controlling position in Advantage Spectrum, L.P. (Advantage) to fraudulently obtain nearly $113 million in bidding credits for license auctions conducted by the FCC. The district court dismissed the claims, applying the public-disclosure bar and finding that FCC filings had disclosed U.S. Cellular’s position in Advantage.

The D.C. Circuit reversed, applying the original source exception. The court emphasized that even if a complaint alleges a fraud that is “substantially the same” as fraud previously disclosed under the first prong, the allegations may still materially add to the publicly available information under the second prong. The court concluded that Advantage’s prior disclosures were not substantially the same as the fraud alleged in the complaints, and that, in any event, the relators qualified as an original source. The court noted that the relators alleged Advantage never functioned as an independent business and that Advantage and U.S. Cellular entered into an agreement for Advantage to transfer its licenses, all allegations that could not have been inferred from Advantage’s FCC filings. As the relators’ allegations materially added to the publicly available information, the D.C. Circuit reversed and allowed the suits to proceed.

The U.S. Cellular decision underscores the central role of relators and public disclosures in FCA litigation. Because qui tam claims are filed under seal, defendants face a lengthy period of uncertainty about the relator’s identity—and the availability of affirmative defenses—while the Government investigates and, sometimes, attempts to settle such claims. Even where a company is confident it has previously disclosed the material facts being investigated, U.S. Cellular Corp. illustrates that it may still face liability if the relators’ claims materially add to publicly available information. Companies should consider U.S. Cellular Corp. when making voluntary disclosures of fraudulent activity and when assessing the strength of defenses to sealed qui tam actions.