U.S. Senator Richard Blumenthal has launched a formal Senate inquiry into Binance, the world's largest cryptocurrency exchange. The investigation follows reports alleging the exchange facilitated approximately $1.7 billion in transactions linked to sanctioned Iranian entities and Russia's "shadow fleet" of oil tankers.
Blumenthal, ranking member of the Senate Permanent Subcommittee on Investigations, sent a letter to Binance CEO Richard Teng demanding documents related to these alleged illegal transfers. The inquiry also seeks information on why compliance personnel who reportedly flagged this activity were suspended or dismissed.
Binance has denied intentionally facilitating sanctions evasion or punishing staff for raising concerns. The exchange stated that flagged accounts were separated and that it cooperates with regulators.
This investigation occurs as Binance claims to have significantly reduced its exposure to sanctioned bodies, reporting a 96% drop in related activity between early 2024 and mid-2025. However, internal investigators reportedly found over 1,500 accounts linked to Iran and funds channeled through intermediaries to entities associated with Iran's Islamic Revolutionary Guard Corps and Russian ships evading sanctions.
The senator's letter also accuses Binance of ignoring clear warning signs and allowing potentially illegal accounts to operate, despite a 2023 settlement with U.S. authorities requiring enhanced anti-money-laundering controls.