Dialysis giant DaVita has reached a tentative settlement with federal investigators to pay $389 million to settle charges that it negotiated agreements with nephrology practices in the Denver area to steer patients to company clinics.

The settlement, still subject to negotiation of specific terms, will resolve the 2010 and 2011 U.S. attorney physician relationship investigations, the company said in an earnings release. A Denver federal grand jury has been investigating the relationship between DaVita and Denver Nephrology, and whether the dialysis company paid kickbacks to the nephrologists in exchange for customers.

Chief Financial Officer Garry E. Menzel said during a call with investors that DaVita would have to buy out or sell to its joint venture partners at fair market value. “In most cases, we would anticipate being the purchaser.” Most likely, he said, that would involve 11 transactions containing 28 dialysis centers.