Headquartered in Irvine California, Arta Health Network and Arta Western Medical Group (collectively known as Arta) were established in 1995 as Independent Practice Associations (IPAs). Each contracts with more than 800 primary care and specialist physicians to provide the entire spectrum of medical and ancillary services to health plan members. Both of Arta’s physician networks cover most areas within Orange County, California. In September 2012, Arta was acquired by HealthCare Partners, a subsidiary of DaVita HealthCare Partners.
Arta Western is contracted with CalOptima, the County's Organized Health System, to serve Medi-Cal members. Arta Health Network serves commercial HMO and senior members under several health plans, including Aetna, Anthem Blue Cross, Blue Shield of California, Care 1st Health Plan, Cigna, Easy Choice, Health Net, Humana, and SCAN.