Senator Richard Blumenthal demanded that Binance, Tether, and crypto companies linked to Donald Trump provide documents as part of investigations.
The recipients were given a deadline of January 4, 2027, after which lawmakers may resort to coercive measures.
The inquiries concern possible conflicts of interest, illegal crypto transactions, and compliance with American law.
US Senator Richard Blumenthal sent a warning to a number of companies and government agencies which, according to him, did not provide the requested information as part of ongoing investigations. Among the recipients were the crypto exchange Binance, the issuer of the USDT stablecoin Tether, as well as World Liberty Financial (WLFI) and Fight Fight Fight LLC, linked to President Donald Trump.
Blumenthal, who is set to head the US Senate Permanent Subcommittee on Investigations (PSI), demanded that the documents be provided by January 4, 2027. Otherwise, lawmakers will consider alternative ways of obtaining information, including the possible use of compulsory powers.
"Please note that refusal to voluntarily provide the requested documents and information by January 4, 2027 will leave the subcommittee no choice but to consider alternative measures to ensure compliance with the requirements," the letters say.
Which companies came under the senator's scrutiny
Regarding World Liberty Financial and Fight Fight Fight LLC, the investigation is related to possible conflicts of interest and the financial activities of the Trump family's crypto projects.
Blumenthal began the review in May 2025 amid reports that companies linked to the president could have violated government ethics requirements, conducted transactions with foreign nationals under federal criminal prosecution, and attracted investment from foreign governments.
In July 2026, the senator also organized public hearings devoted to the Trump family's crypto business. In particular, participants reviewed testimony from investors in the TRUMP memecoin who reported financial losses.
A separate area concerns Binance and Tether. Blumenthal is examining the possible use of digital assets in illegal financial operations, as well as the crypto companies' ties to representatives of the US administration.
In September 2026, the Democratic minority of the PSI published a report on the role of USDT in Iran's shadow banking system. Researchers examined 846 crypto wallets linked to Tehran and regional groups. According to the document, 84% of these addresses used USDT primarily or exclusively.
Based on the data obtained, Blumenthal called on the US Treasury and Justice Department to review Tether's activities for compliance with sanctions legislation and anti-money laundering requirements.
The company itself rejected claims that USDT is a safe tool for sanctioned entities. Tether representatives emphasized that they cooperate with law enforcement agencies and help block assets linked to illegal activity.
Claims against Binance had also arisen earlier. In April 2026, Blumenthal requested information from American agencies on the status of the exchange's independent monitors amid reports of crypto transactions worth more than $1.7 billion linked to Iran.
Additional attention from lawmakers to Binance and World Liberty Financial is due to their alleged financial ties to the Trump administration. Earlier, a group of senators, including Blumenthal, demanded an investigation into the circumstances of the presidential pardon of Binance founder Changpeng Zhao.
The authors of the letter allowed for a possible conflict of interest amid the exchange's cooperation with WLFI. At the same time, the lawmakers' suspicions themselves are not proof of violations.
Other areas of investigation
In addition to crypto companies, Blumenthal sent warnings to representatives of federal agencies and the technology sector.
In particular, the letters were received by:
US Secretary of Homeland Security Markwayne Mullin — in connection with the investigation of alleged abuses by immigration services;
technology companies and other publicly known sponsors of the construction of the White House ballroom — amid suspicions of possible receipt of government preferences for donations;
Chairman of the Federal Communications Commission (FCC) Brendan Carr — over questions regarding the agency's use of its powers and possible pressure on the media.
The senator expects that after the leadership of the PSI passes to the Democrats, the subcommittee will be able to more actively pursue the provision of documents, including through coercion.