On April 3, 2020, the Federal Communications Commission and the Federal Trade Commission sent warning letters to three gateway providers, demanding that they stop allowing robocalls conveying COVID-19 scams on their networks. The FCC and FTC gave the providers 48 hours to comply with the request, and threatened to order all traffic on these carriers blocked.
Concurrently, the FCC and FTC issued a letter to USTelecom, a trade association representing providers of wireless, internet, and voice services in the United States, authorizing its member companies to begin blocking calls from the three providers if, after 48 hours, the scam robocalls had not stopped.
FCC press release | USTelecom letter | Connexium letter | SIPJoin letter | VoIP Terminator letter