Sanctions programs prohibit dealings with designated persons and, for comprehensive programs, with entire jurisdictions. Civil liability is generally strict — intent is not required.

Blocking versus rejecting. Property of a blocked person must be frozen and reported; transactions merely prohibited must be rejected. Reporting deadlines apply to both, and misclassifying one as the other is a common failure.

The fifty percent rule. Entities owned fifty percent or more, directly or indirectly, individually or in the aggregate, by blocked persons are themselves blocked though they may not appear on any list. Screening names alone does not catch these; ownership data does.

Screening design. Fuzzy matching tolerances, transliteration handling, and the frequency of rescreening the existing customer base against list updates. Tuning that suppresses matches to reduce alert volume is a recognized enforcement theme.

Voluntary self-disclosure is a substantial mitigating factor and is the single most consequential decision after a violation is found. It requires speed, completeness, and a remediation plan.

Facilitation by a domestic institution of a transaction it could not conduct itself is prohibited, which catches referrals and advisory activity, not only payments.

Licenses. General and specific licenses authorize otherwise prohibited activity, and their conditions are narrow. Reliance on a general license should be documented at the time.