# Specially Designated Nationals List The **Specially Designated Nationals and Blocked Persons List** is the master roster maintained by the [[Office of Foreign Assets Control]] of individuals, entities, vessels, aircraft and digital-currency addresses whose property is blocked and with whom U.S. persons are generally prohibited from dealing. An entry takes effect the moment it is posted on OFAC's website; the Federal Register notice follows days later. The list runs to many thousands of entries across every active program. Two features make the list smaller than the universe it governs. The **50 percent rule** (guidance revised August 13, 2014) blocks any entity owned half or more in the aggregate by listed persons without ever listing it, and the dollar-clearing system extends the freeze through correspondent banking to parties who were never designated. The list is the visible surface of the sanctions system, not its boundary. The full designation and delisting machinery is mapped in [[Sanctions Designation Pipeline]]. This is a stub — expand with the non-SDN lists (SSI, FSE, CAPTA, NS-MBS), the consolidated-list architecture, and the entry-count series. ## See Also - [[Sanctions Designation Pipeline]] · [[Office of Foreign Assets Control]] - [[International Emergency Economic Powers Act]] · [[Secondary Sanctions]]