Qui Tam

A provision of the False Claims Act which allows private
citizens who have knowledge of fraud committed against the federal government
to file a lawsuit on behalf of the government.

The Latin term “qui tam” is shorthand for the longer
phrase, “qui tam pro domino rege quam pro
se ipso in hoc parte sequitur
,” which translates as “he who [sues] for the
king as well as for himself.”