If I'm understanding the recent guidance correctly, our primary responsibility is gathering registrations, conducting risk, etc. on the MSBs in our customer database that are registered with FinCEN. Are we required to train staff to be "on the lookout" for customers that we think may be an MSB based on the types of transactions we've seen?
Before this guidance was issued, I had a list of possible MSBs, because of the cash activity I noticed on a report. I completely understand how to handle a registered MSB but what about those unregistered that may simply be unaware of what's required? How far do we take it?

It probbly depends on your regulator but ours (FDIC) recommended we "strongly suggest" to the business that they register. I think that providing the msb.gov address would be a good start and then document what you said to whom and when. It is my opinion that you would be offering legal and or tax advice to do much more than provide the information.

When your financial institution is opening new accounts for business entities, you may want to have the entity complete a commercial account checklist that asks various questions that will help you conduct your risk assessment including determining if a new customer is an MSB.

As for your current customers, if you suspect they are an MSB in accordance with the definition of an MSB (31 CFR 103.11 (uu)), I would have the person responsible for the account (branch manager) contact or visit the customer and ask a few questions. If it appears they would be classified as an MSB, require them to present the materials as stated in the Interagency guidance. Additionally, if they are classified as an MSB and they are not registered, you will need to file a SAR on them.