The suit, filed in L.A. Superior Court, seeks to force a unit of Tenet Healthcare Corp. to give up ownership and control of USC University Hospital. The school claims that various lawsuits and investigations have impacted Tenet's ability to operate the hospital. The suit comes two months after the Dallas-based company (formerly based in Santa Barbara) resolved a four-year-long U.S. Department of Justice probe into Medicare and other billing disputes for about $900 million. Tenet spokesman Steve Campanini said that the suit "appears to be an unfortunate negotiating tactic." Prominent L.A. attorney Marshall Grossman, who is representing USC, said the university ended up with more than $100 million less than it sought for capital improvements.