What must I do before I enter into a covered transaction with another person at the next lower tier?

When you enter into a covered transaction with another person at the next lower tier, you must verify that the person with whom you intend to do business is not excluded or disqualified. You do this by: (a) Checking SAM.gov Exclusions; or (b) Collecting a certification from that person; or (c) Adding a clause or condition to the covered transaction with that person.