[3] In August 1998, the company merged with Principal Health Care and moved its headquarters to Bethesda, Maryland.

[3] In October 2000, the company acquired WellPath, the managed care subsidiary of Duke University Health System, for $20.7 million.

[4] In October 2010, the company acquired MHP (Mercy Health Plans), an insurer with approximately 180,000 members in Missouri and northwest Arkansas.

[5] In January 2012, the company acquired Children's Mercy's Family Health Partners.

[6] In May 2013, the company was acquired by Aetna for $5.7 billion, who then outsourced all IT work and laid off thousands of key personnel[2][7]