Shares of IPC The Hospitalist Co. hit a 52-week low Wednesday after disclosing that the U.S Justice Department wants to examine several years’ worth of claims that the company submitted to Medicare and Medicaid.

The North Hollywood operator of in-hospital physician practices said it received a civil investigative demand from the U.S. Attorney’s Office for the Northern District of Illinois seeking documents dating as far back as 2003.

In the letter received on Monday, the attorney’s office demanded “production of a wide range of documents relating to the company’s Medicare and Medicaid participation, physician arrangements, operations and compliance programs,” said IPC in its the Securities and Exchange Commission filing on Wednesday.

“The company has a strong compliance focus, and believes that it operates with appropriate billing policies, procedures, provider training and compliance programs,” IPC said. “The company intends to meet with representatives of the government to discuss the scope of the CID and the production of responsive documents.”

The SEC disclosure comes on the eve of the company’s investor day in New York on Thursday morning.

IPC, which went public in early 2008, has been buying up hospital and nursing facility physician practices nationwide, announcing a trio of acquisitions in the last two weeks alone. It’s doctors, known as “hospitalists,” work at more than 500 hospitals, assisted-living facilities and nursing centers in 21 states.

Shares closed down $4.87, or 17 percent, to $23.17 on the Nasdaq.