When the US Treasury moved against Tornado Cash in 2022, it sent shockwaves through crypto. For a period, smart-contract addresses appeared on the OFAC SDN list before Treasury later removed those addresses on March 21, 2025. Understanding that full arc—and how sanctions interact with stablecoin blacklists—is essential for anyone operating in crypto.
Sanctions overview
International sanctions are economic restrictions imposed by governments to achieve foreign policy goals. They can target countries, organizations, or individuals, and they restrict what financial dealings are permitted.
OFAC (US)
Office of Foreign Assets Control
Part of the US Treasury. Administers the SDN (Specially Designated Nationals) list.
Has extraterritorial reach—affects anyone using USD or US financial system.
Source
EU Sanctions
European Union
Maintained by the Council of the European Union. Binding on all EU member states
and their residents. Often aligns with but is distinct from OFAC.
Source
UN Sanctions
United Nations Security Council
Binding on all UN member states. Generally focused on terrorism, nuclear
proliferation, and human rights. Often the baseline for national sanctions.
Source
Multiple jurisdictions apply
You may be subject to sanctions from multiple jurisdictions simultaneously. A European exchange using USD-denominated stablecoins must comply with both EU sanctions AND OFAC requirements.
OFAC and the SDN list
OFAC maintains the SDN (Specially Designated Nationals) list—a database of individuals, entities, and now cryptocurrency addresses that US persons are prohibited from transacting with.
What's on the SDN list?
Individuals
Named persons associated with sanctioned regimes, terrorism, or organized crime.
Entities
Companies, organizations, government bodies that are sanctioned.
Vessels & Aircraft
Ships and planes used for sanctions evasion or by sanctioned parties.
Crypto Addresses
Since 2018, OFAC has included cryptocurrency wallet addresses directly on the SDN list. Source
Who must comply?
OFAC sanctions apply to:
- US persons - Citizens, residents, and anyone physically in the US
- US companies - Including foreign subsidiaries in many cases
- Transactions in USD - Even between non-US parties, if cleared through US banks
- US-origin goods/services - Including software and technology
The Tornado Cash precedent
In August 2022, OFAC designated Tornado Cash, an Ethereum mixing protocol. At the time, the move was unprecedented: smart-contract addresses themselves appeared on the SDN list, and the market treated interaction with those addresses as a serious sanctions issue.
OFAC designates Tornado Cash
Treasury adds Tornado Cash addresses to the SDN list and cites laundering tied to North Korean actors, including funds from the Axie Infinity / Ronin hack. Source
Immediate market reaction
Circle blacklists USDC already held in Tornado-related addresses, GitHub removes repositories, and many DeFi front ends and service providers block associated wallets.
Fifth Circuit narrows OFAC's theory
The court holds that OFAC exceeded its authority as to immutable Tornado Cash smart contracts, reshaping the legal analysis around code-based sanctions. Source
Treasury removes Tornado Cash addresses
Treasury delists the Tornado Cash addresses. That means Tornado Cash is not accurately described today as an active SDN designation, even though the episode still matters historically. Source
What Tornado Cash means for you
The operational impact from 2022 through 2025 was immediate and lasting, even though the designation itself was later unwound:
Addresses interacting with Tornado were heavily scrutinized
Even legitimate privacy use cases resulted in addresses being flagged by compliance tools, and many users found access to exchanges or DeFi interfaces restricted.
Stablecoin issuers took visible action
Circle blacklisted USDC already sitting in Tornado-related addresses in 2022, demonstrating how quickly issuer controls can be used during sanctions events.
Mixer proximity became a long-term compliance signal
Even after delisting, many compliance teams still treat recent or repeated mixer exposure as high risk and subject it to enhanced review.
EU and UN sanctions
While OFAC gets the most attention in crypto, EU and UN sanctions also matter:
EU Sanctions
The EU maintains its own consolidated sanctions list, which often—but not always— aligns with US sanctions. Key differences:
The EU's Markets in Crypto-Assets Regulation (MiCA), in effect for stablecoins since June 2024, requires EU-regulated issuers of asset-referenced tokens and e-money tokens to maintain compliance programs that include sanctions screening. This creates an explicit regulatory link between stablecoin issuance and sanctions enforcement in EU law.
UN Sanctions
UN Security Council sanctions are binding on all UN member states and often form the foundation for national sanctions programs:
How stablecoin issuers respond
Stablecoin issuers have adopted different approaches to sanctions compliance:
- Has frozen addresses tied to sanctions, law-enforcement investigations, and sanctioned jurisdictions
- Cooperates with law enforcement agencies on sanctions evasion investigations
- Can permanently burn frozen USDT balances using the destroyBlackFunds contract function
- Less comprehensive formal policy documentation than licensed issuers
- Publicly documents sanctions compliance policies and blacklist procedures
- Promptly froze USDC held in Tornado-related addresses in August 2022
- Regulated as a US money transmitter; authorized as an electronic money institution in the EU under MiCA
- Publishes transparency reports on reserve composition and compliance controls
No stablecoin is sanctions-neutral
All major USD stablecoins have connections to the US financial system that make OFAC compliance effectively mandatory. Even DAI, a decentralized stablecoin, is backed partly by USDC and thus inherits some sanctions exposure. Circle's USDC terms and MiCA USDC whitepaper are useful primary references for Circle's stated control structure and compliance posture.
Protecting yourself
Whether you're an individual user or running a business, here's how to manage sanctions exposure:
Screen counterparties
Before large transactions, check addresses against OFAC SDN list and stablecoin blacklists. Tools like Eagle Virtual aggregate this data.
Avoid mixing services
Even though Tornado Cash was delisted on March 21, 2025, mixer use still creates significant compliance and counterparty risk. The privacy benefit often is not worth the scrutiny that follows.
Document transactions
Keep records of counterparty information, transaction purposes, and any screening you performed. This helps if questions arise later.
Monitor ongoing exposure
Sanctions designations happen without warning. Set up monitoring for addresses you've transacted with in case they become sanctioned later.
Understand your jurisdiction
Different sanctions apply in different places. Know which sanctions regimes apply to you based on your citizenship, residence, and business operations.
Seek legal advice
For business operations, consult with lawyers who understand both crypto and sanctions law. This area is complex and evolving rapidly.
Key takeaways
Frequently asked questions
Do OFAC sanctions apply to non-US crypto users?
OFAC sanctions primarily bind US persons, but their reach extends further. Any transaction touching USD, cleared through a US correspondent bank, or involving US-origin technology can fall within OFAC jurisdiction. Non-US firms should evaluate correspondent-banking relationships, counterparty exposure, and secondary sanctions risk.
Can stablecoin issuers freeze my wallet without notice?
Yes. Both Tether and Circle can blacklist addresses at the smart-contract level, freezing all tokens held at that address. These actions can occur without advance notice, typically in response to sanctions designations, law enforcement requests, or internal compliance decisions.
Is Tornado Cash still sanctioned?
No. Treasury removed Tornado Cash addresses from the SDN list on March 21, 2025, following the Fifth Circuit's November 2024 ruling that OFAC exceeded its authority regarding immutable smart contracts. However, many compliance programs still treat historical Tornado Cash interaction as elevated risk, and mixer exposure broadly remains a compliance concern.
How does MiCA affect stablecoin sanctions screening in the EU?
MiCA requires EU-regulated issuers of asset-referenced tokens and e-money tokens to maintain compliance programs that include sanctions screening against EU consolidated lists. This creates an explicit regulatory link between stablecoin issuance and sanctions enforcement in EU law.
Primary sources
- OFAC Sanctions Compliance Guidance for the Virtual Currency Industry
- Treasury announcement of the first SDN-listed crypto addresses
- Treasury designation of Tornado Cash
- Fifth Circuit Tornado Cash opinion
- Treasury delisting of Tornado Cash addresses
- EU sanctions overview
- UN Security Council sanctions overview
- Circle USDC terms
- Circle MiCA USDC whitepaper