Thanks to their filings under the False Claims Act, the Justice Department recovered $3.3 billion in the past year.
The False Claims Act pertains to cases of fraud against the government.
A provision allows citizens to file lawsuits on the government's behalf and keep a portion of any penalties or fines collected.
In the previous fiscal year, which ended September 30th, $3 billion was collected from health care fraud cases, and more than $900 million came from mortgage companies as part of a multi-billion dollar foreclosure settlement.
The largest, single payout came from GlaxoSmithKline.
The company paid one-and-a-half billion dollars to settle allegations that included promoting drugs for uses other than those approved by the Food and Drug Administration.
In that particular case, the whistleblowers who uncovered the fraud collected awards totaling $131 million.