What is the OFAC SDN List?
The Specially Designated Nationals and Blocked Persons List is the US Treasury's Office of Foreign Assets Control's master list of individuals, entities, vessels and aircraft whose assets are blocked and with whom US persons are generally prohibited from dealing. US persons (citizens, permanent residents, US-incorporated entities, and anyone physically in the US) must block property and reject transactions involving SDN parties. The list is updated as needed — sometimes daily.