U.S. Senator Richard Blumenthal, the ranking Democrat on the Senate Permanent Subcommittee on Investigations, has formally requested extensive records from Cantor Fitzgerald regarding its business relationship with Tether, the issuer of the world’s largest stablecoin. In a letter dated October 8 addressed to Cantor Chairman Brandon Lutnick, Blumenthal sought documentation covering revenue, custody arrangements, sanctions compliance and any financial ties involving the Lutnick family.

The request covers the period from January 1, 2023, onward and sets a response deadline of October 23. It intensifies scrutiny of the partnership between the New York-based investment bank and the company behind the USDT stablecoin, following a September report by Democratic subcommittee staff that alleged widespread use of USDT in Iran’s shadow banking networks.

Scope of the Records Request

Blumenthal asked Cantor to describe its monitoring of Tether’s compliance with U.S. banking and sanctions laws. He specifically inquired about steps taken to examine allegations that USDT has facilitated Iranian shadow banking and efforts to evade sanctions on Russia. The letter also seeks all communications involving Commerce Secretary Howard Lutnick related to Tether, including those occurring after he left the firm.

Additional questions focus on the terms of Howard Lutnick’s divestiture of Cantor ownership to his children and whether Tether provided any loans or other financing connected to that transfer. Blumenthal further requested information on whether Cantor requires independent audits of Tether, whether the bank has ever considered ending the relationship, and what revenue Cantor has earned from its Tether-related activities.

In a related statement within the letter, Blumenthal added that just as Tether has generated substantial returns from stablecoin activity linked to alleged illicit uses, Cantor has also profited from the partnership.

Cantor’s Stake and Custody Role

Cantor Fitzgerald’s relationship with Tether began in 2021, when the bank started serving as a custodian for a portion of the U.S. Treasury securities that back the stablecoin’s reserves. The arrangement later expanded. In 2024, while Howard Lutnick served as Cantor’s chairman and chief executive, the firm acquired rights to a reported 5 percent stake in Tether.

Blumenthal alleged that the estimated value of that stake rose from $600 million to $10 billion after President Donald Trump returned to office. He further stated that Howard Lutnick received more than $250 million during the same period, including a $192 million distribution from Cantor Fitzgerald. The letter notes that Cantor reportedly continues to custody tens of billions of dollars in Tether’s U.S. Treasury bill reserves.

Howard Lutnick stepped down from Cantor after the Senate confirmed him as commerce secretary in February 2025. His son Brandon was named chairman, and another son was appointed vice chairman. A separate Senate document previously recorded Howard Lutnick denying that Cantor held a Tether investment.

Background on Iran-Linked Allegations

The latest letter follows a September investigation by Democratic staff on the Permanent Subcommittee on Investigations. That report examined 846 digital-asset wallets sanctioned or targeted for suspected links to Iran and related organizations. Investigators found that 84 percent of those wallets had conducted transactions exclusively or almost exclusively in USDT.

Blumenthal has called on the Treasury Department and Justice Department to investigate potential sanctions violations. Tether has disputed characterizations that it fails to act against illicit activity. The company stated that it has worked with law enforcement for years and helped freeze nearly $550 million in Iran-linked USDT during 2026. Tether CEO Paolo Ardoino said the firm has supported more than 2,900 investigations worldwide and assisted in freezing over $4.9 billion in assets overall, including more than $2.4 billion in cooperation with U.S. authorities.

As of June 30, Tether reported $187.75 billion in assets, $183.64 billion in liabilities and a $4.11 billion excess over liabilities.

Next Steps and Political Context

Cantor Fitzgerald and Tether did not immediately respond to requests for comment in connection with the letter. Blumenthal issued the request in his capacity as ranking minority member. Democrats currently hold minority status on the subcommittee and possess limited formal investigative tools. A shift in Senate control after the November midterm elections could expand their authority, including the potential use of subpoena power.

The inquiry centers on transparency around compliance practices, governance of the ownership transfer and the financial outcomes of a multiyear commercial relationship between a major Wall Street firm and the dominant dollar-pegged stablecoin issuer.