Fresenius Medical Care (NYSE:FMS; ETR:FRE) agreed to pay more than $5 million to resolve allegations that its dialysis clinic business over-billed Medicare for hepatitis B tests.

The country’s largest dialysis clinic operator, Fresenius Medical Care North America agreed to pay $5.2 million to settle federal prosecutors’ allegations that it billed Medicare for tests of dialysis patients it knew to be immune to the liver disease. In many cases Fresenius billed for the tests against physician’s orders and without documenting the tests’ necessity, according to prosecutors in the Massachusetts U.S. attorney’s office in Boston.

A former Fresenius employee, Christopher Drennen, who filed a qui tam whistleblower lawsuit is slated to receive 27.5%, or $1.4 million, of the settlement.

“Providers are expected to closely follow Medicare rules and bill properly – nothing more, nothing less,” U.S. attorney Andrew Lelling said in prepared remarks. “When that obligation is violated, government health care programs – and American taxpayers – pay the price. This settlement is an example of how whistleblowers and government can work together to recoup and deter over-billing practices.”

FMS shares closed up 1.8% at $32.67 yesterday and gained another 0.2% to $32.74 in pre-market trading today.