We run it weekly, and whenever the SDN is updated. We also do OFAC on account opening (Loans-Transunion;Deposits-FIS) so anything new is covered.
We used to do it nightly, but given the fact that we've never had a true positive the risk didn't seem to be there to have to run/check it daily, which I viewed as overkill.
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I hear and I forget. I see and I remember. I do and I understand.--Confucius