A federal judge has sanctioned one of the nation’s largest health care corporations for “unacceptable” conduct in a whistleblower lawsuit that he said spoiled its required disclosure of information with false testimony—a decision that could force the company to reimburse whistleblower attorneys as much as $2 million.

U.S. District Senior Judge Charles Pannell Jr. ruled that DaVita Inc., which operates more than 2,000 kidney dialysis clinics, demonstrated “enough of a showing of bad faith” to warrant reopening discovery in the seven-year-old case. The suit, filed by two former employees who worked at DaVita clinics in Georgia, accuses the company of defrauding the federal government of hundreds of millions of dollars.