FDIC, which insures every deposit account to begin with, has a legitimate right to know each insured account.  I find no reason why banks would not be willing to provide to FDIC an electronic upload of every account and accountholder information.  This mega database would be available to OFAC and FINCEN to scan for any account they desire.  This would relieve Banks to scan twice a month for FINCEN and every time there is a change to the OFAC list.  This would be a more effective method to search for accounts.  All hits would be referred back to the Bank for follow up.