A hospitalist company that works with thousands of post-acute care facilities is officially facing federal charges that its clinicians routinely overbilled Medicare and Medicaid, authorities announced Tuesday.

In 2009, a whistleblower alleged that California-based IPC The Hospitalist Company pressured its clinicians to “upcode” — that is, bill government health plans for more expensive services than were provided. The federal government has the option to join whistleblower cases, and it opted to do so in this matter, filing a legal complaint Monday in U.S. District Court in Illinois. The government had announced its intention to file a complaint in December.

“As a result of corporate/management pressure, and/or in keeping with IPC corporate culture and expectations to maximize billings, IPC hospitalists have routinely and systematically submitted upcoded claims for payment to the United States,” the complaint states.

Total overpayments to IPC have totaled millions, according to a statement from the U.S. Attorney for the Northern District of Illinois. Under the False Claims Act, the government can recover three times its damages and up to $11,000 for each false claim submitted.

Hospitalists are physicians who specialize in caring for patients in the hospital or long-term care settings. IPC employs about 2,500 hospitalists who provide services to about 400 acute and 1,100 post-acute facilities in 28 states, according to court papers.

In December, an IPC spokesman told McKnight’s that the company could not comment on an ongoing legal matter. The company has engaged in preliminary settlement talks, according to a Securities and Exchange Commission filing.