Checking counterparties and addresses against government sanctions lists, such as the US Treasury’s Specially Designated Nationals list.
Why it matters
Sanctions authorities designate blockchain addresses as well as people and entities. The Ronin theft is an example: OFAC added an address associated with it to the SDN list, which is also the basis on which the attribution is reported.
What you can check
Designations are published. The OFAC SDN list names sanctioned parties and, increasingly, specific addresses; other jurisdictions maintain their own. Screening is the service’s obligation, but the underlying lists are public and can be read directly.
Not advice. Definitions are for understanding, not instruction. Nothing here is financial, legal, tax or security advice.