Tether has frozen more than $544 million in crypto holdings after being asked to assist Turkish authorities investigating an alleged illegal online betting and money‑laundering network. Istanbul prosecutors announced last week they had seized roughly €460 million (about $544 million) tied to Veysel Sahin, accused of operating unlawful betting platforms and laundering proceeds. Tether Holdings SA, issuer of the USDT stablecoin, was later identified by CEO Paolo Ardoino, who told Bloomberg law enforcement provided information and the company complied with Turkish law. Ardoino said Tether follows equivalent procedures when cooperating with agencies such as the U.S. Department of Justice and the FBI.
The freeze is part of a broader probe into underground gambling and payment networks in Turkey; Bloomberg reported related investigations have resulted in Turkish authorities seizing more than $1 billion in assets. Analysts say stablecoin issuers have increasingly been asked to block addresses tied to illicit activity as regulators and law enforcement step up efforts.
Blockchain analytics firm Elliptic reported that Tether and Circle had blacklisted about 5,700 wallets holding roughly $2.5 billion by late 2025, with roughly three‑quarters of those addresses containing USDT at the time of freezing. Tether told Bloomberg it has assisted law enforcement in over 1,800 investigations across 62 countries, which the company says has led to about $3.4 billion in frozen USDT linked to alleged criminal activity.
Despite such compliance steps, USDT remains under scrutiny. U.S. prosecutors recently charged a Venezuelan national accused of laundering about $1 billion largely using USDT, and blockchain researchers have traced significant USDT flows to potential sanctions‑evasion channels. Forensic firms map how suspected proceeds move from individuals through exchanges, mixers and other services to trace illicit finance chains.
Previous industry analyses underscore the scale of the issue: blockchain analytics firm Bitrace reported that $649 billion in stablecoins — about 5.14% of total stablecoin transaction volume in 2024 — passed through addresses it labeled high‑risk, with Tron‑based USDT accounting for more than 70% of that activity.
Meanwhile, USDT’s market footprint has continued to expand. Cointelegraph reported USDT reached a record market capitalization of $187.3 billion in Q4 2025, up about $12.4 billion for the quarter despite broader market volatility tied to an October liquidation cascade. Competing coins fared worse: Circle’s USDC was largely flat in the quarter, and Ethena’s USDe lost roughly 57% of its value. Network usage metrics also rose: monthly active USDT wallets climbed to 24.8 million — roughly 70% of all stablecoin‑holding addresses — while quarterly transfer volume hit about $4.4 trillion across 2.2 billion transactions, setting new on‑chain records.
The reporting reflects Cointelegraph’s coverage; readers are encouraged to verify details independently and consult original sources and official statements for the latest developments.