Beneficial interest is a situation that arises when a document you’re asked to notarize would give you some kind of improper benefit beyond the standard notarization fee. Usually this is financial, but it can be any sort of gain or advantage.
Notarizing a document that would transfer ownership of a car or home to you are obvious cases of beneficial interest. However, notarizing a document that gives your family free tickets to a baseball game would be beneficial interest as well.
Even if not spelled out directly in state law, the NNA recommends that you do not notarize any document that gives you a beneficial interest. That includes potential benefits, including inheritances. Both potential and actual beneficial interest can be used to challenge a document’s validity in court.