(a) A civil action under section 3504 may not be filed more than three years after the date of discovery by the Attorney General or, in any event, not more than 10 years after the date on which the violation of section 3503 was committed.
(b) In any action brought under section 3504, the Government, or the qui tam plaintiff is required to prove all essential elements of the cause of action, including damages, by a preponderance of the evidence.
(c) Notwithstanding any other law, a guilty verdict rendered in a criminal proceeding charging false statements or fraud, whether upon a verdict after trial or upon a plea of guilty or nolo contendere, estops the defendant from denying the essential elements of the offense in any action that involves the same transaction as in the criminal proceeding and which is brought under section 3504.