Mid Atlantic Medical Services

Mid Atlantic Medical Services, Inc. (MAMSI) was a prominent managed healthcare company that provided health insurance products and services primarily in the Mid-Atlantic region of the United States. The company operated several health maintenance organizations (HMOs) and preferred provider organizations (PPOs), including MD-Individual Practice Association and Optimum Choice. MAMSI served a broad customer base including individuals, small businesses, and large employer groups across Maryland, Virginia, Washington, D.C., and Delaware. In 2004, the company was acquired by UnitedHealth Group for approximately $3 billion, leading to its integration into the UnitedHealthcare business segment.