CVS Caremark

Early years

CVS Caremark was founded in 1993 as MedPartners, Inc. in Birmingham, Alabama, by several local businessmen as a physician practice management (PPM) company. Larry House, an executive from HealthSouth, was brought on to serve as the company's first CEO.

MedPartners went public in February 1995 and began buying up other PPM business around the country. In August 1995, MedPartners announced the acquisition of Mullikin Medical Enterprises, a PPM company based in California. In December 1995, MedPartners acquired Pacific Physicians Services, a PPM company based in Redlands, California.

The company continued to grow by acquiring physician practice groups, including the Kelsey-Seybold Clinic in Houston, Texas, the Summit Medical Group in Summit, New Jersey, and the Ross–Loos Medical Group in Los Angeles, California. By 1996, MedPartners was the largest PPM company in the United States and became a Fortune 500 company the following year.

Caremark International

Caremark International was founded in 1979 in Newport Beach, California, as a provider of specialized medical services and products to chronically ill patients at home. It also operated the second largest mail-order pharmacy benefit management (PBM) business in the country. Baxter International, then known as Baxter Travenol, acquired Caremark in 1987. Baxter spun off Caremark in 1992 and based it in Northbrook, Illinois, near Baxter's Deerfield headquarters. Included in the spin-off was the at-home intravenous drug business, the mail-order pharmacy business, the physician practice management business, and Baxter's chain of physical therapy and sports medicine clinics. Caremark sold its at-home intravenous drug business to Coram in February 1995 followed by its physical therapy and sports medicine business to HealthSouth later that year in October. MedPartners announced it would acquire Caremark for $2.5 billion in May 1996.

Canceled merger and PPM exit

MedPartners announced in October 1997 it would be acquired by PhyCor, Inc., a much smaller PPM competitor based in Nashville, Tennessee, for $6.8 billion. MedPartners and PhyCor called off the merger in January 1998 after problems were discovered during due diligence with MedPartners' western PPM operations. Larry House resigned as chairman and CEO several weeks later. Richard Scrushy, a MedPartners' board member, stepped in as interim chairman and CEO while continuing to serve as chairman and CEO of HealthSouth. In March, Edwin "Mac" Crawford was selected by the board of directors as MedPartners' new CEO. Scrushy retained the chairman role until December 1998 when he relinquished it to Crawford.

MedPartners' board of directors conducted a review of its businesses after the failed merger and decided to sell the clinics that made up the PPM business and focus on growing the Caremark PBM business, which accounted for $2.3 billion of MedPartners' $6.3 billion total revenue for 1997. MedPartners also sold its hospital-based physician-management unit, Team Health, to Madison Dearborn Partners and Team Health's management team in 1999.

Caremark Rx

In 2000, after completing the sales of its clinics tied to the physician management business, MedPartners changed its name to Caremark Rx, Inc. to reflect the name of its only business unit.

In 2003, it merged with AdvancePCS. That same year, Caremark moved its headquarters from Birmingham, Alabama, to Nashville, Tennessee. Following its merger with AdvancePCS, the company continued to operate a mail-order pharmacy operation in Birmingham that employed 400 people until 2010.