reporting fraud

you report it to the perp and ask for some kickback, or else.

Propably the same for any other professional accountant. All licenced accountants have an ethical responsibility to their client/employer.

If there is no documentation, then you can either let the person know that you are aware of their fraudulant activities or you can report it to their immediate supervisor. Just make sure you have documentation to support your suspicions of fraud. Make notes as to who, when and what information was passed on and any action taken, if any. After reporting it to the proper level of management, it is technically out of your hands. Or you can wait for several weeks and see if any activity was taken. If none, then discuss it with the next level of management.