The predecessor of the company was founded in 1978 by Samuel J. Tibbitts as a subsidiary of the Lutheran Hospital Society of Southern California.

[3] In 1993, Alan Hoops replaced Terry Hartshorn as president and CEO.

[6] In December 2005, the company was acquired by UnitedHealth Group.

[8] The company continued to market health plans under the PacifiCare and SecureHorizons names until 2011, when it changed to the UnitedHealthcare name.

[9] The company sponsored Newman/Haas Racing for the 2003 CART season, the 2004 Champ Car season, and the 2005 Champ Car season and donated to support The Painted Turtle.