Sen. Richard Blumenthal, the top Democrat on the Permanent Subcommittee on Investigations, asked for revenue figures, custody records and Lutnick family communications. As a minority member he cannot compel answers before the midterms.
The firm that holds most of Tether's reserves in the United States has been asked to explain the relationship in writing.
Sen. Richard Blumenthal of Connecticut, ranking member of the Senate Permanent Subcommittee on Investigations, sent a letter on Thursday to Brandon Lutnick, chairman of Cantor Fitzgerald. He asked the firm to preserve all records related to Tether and to answer 13 sets of questions by Oct 23, 2026.
"While Tether claims to operate out of El Salvador, the vast majority of its assets reside in the United States under your custodianship," Blumenthal wrote.
What the letter asks for
The requests include the annual revenue Cantor has received from its Tether partnership, the amount the Lutnick family has made from it, and whether Cantor requires regular independent audits of Tether's assets. Blumenthal also asked what Cantor does to monitor Tether's compliance with sanctions and anti-money-laundering rules, under what circumstances Cantor would end the relationship, and for records of its custody arrangement.
The letter seeks records of Cantor's ownership stake in Tether, the terms under which Howard Lutnick, Cantor's former chairman and now commerce secretary, gave up his stake in the firm, and any loan from Tether that enabled him to transfer it to his children. It also asks for communications between Cantor and Tether about compliance, Tether's reserves, fundraising and the family's ownership interests. Most requests cover the period from Jan 1, 2023.
The figures in the letter
Blumenthal estimated that Cantor's 5% stake in Tether, worth $600 million when President Trump returned to office, is now worth about $10 billion, on top of "the tens of millions of dollars the company collects every year from the assets it holds for Tether." That would be an increase of roughly 16-fold. He also wrote that Howard Lutnick has made more than $250 million over the same period, including a $192 million distribution from Cantor.
Those are the senator's figures. Neither Cantor nor Tether commented immediately.
The letter follows a Sep 28, 2026 report by the subcommittee's minority staff that it says found Tether props up Iran's shadow banking system.
The limits
Blumenthal sent the letter as the ranking member of a subcommittee his party does not control. A minority letter is a request, not a subpoena, and Cantor is not obliged to answer. Republican Sen. Ron Johnson, the subcommittee's chairman, was copied.
The letter lands the same week that Europe's securities regulator told licensed crypto platforms to stop serving stablecoins that lack European authorization, a group that includes Tether's USDT.
Opposing readings
One reading is that political risk to Tether's U.S. custody arrangement is rising. Congressional scrutiny of its main reserve custodian, European restrictions and sanctions allegations are arriving together, and a change in Senate control after Nov 3, 2026 would give Democrats subpoena power.
A second reading is that this is a partisan letter with no enforcement force. It carries no compulsory process, makes no finding of wrongdoing by Cantor or Tether, and Tether has said in the past that it freezes tokens linked to illicit activity.
The dates
Oct 23, 2026 is the response deadline. The Nov 3, 2026 elections will determine whether the subcommittee's minority becomes its majority. Any response from Cantor or Tether, and any shift in USDT's share of stablecoin trading against regulated rivals, are the next markers.