OFAC SDN sanctions screening — checks whether a person, company, vessel, or aircraft appears on the US Treasury Specially Designated Nationals list. Returns match score, sanctions program(s), and entity type. Covers ~19,000 entries including RUSSIA-EO14024, SDGT, IRAN, DPRK, TCO, and 30+ programs. Use for payment compliance, KYB/KYC, AML checks, and counterparty due diligence.