Thomas P Mac Mahon

Thomas P. Mac Mahon was elected a director of Express Scripts in March 2001. Mr. Mac Mahon served as President and Chief Executive Officer and a member of the Executive and Management Committees of Laboratory Corporation of America Holdings or "LabCorp", the second largest independent clinical laboratory company in the U.S., from January 1997 until his retirement on December 31, 2006. Following his studies at Saint Peter’s, Mac Mahon went on to become a pioneer in the field of medical diagnostics. During his more than 40-year career in healthcare, he worked at Roche Diagnostics, where he played a leading role in commercializing the use of PCR, a Nobel Prize-winning development that led to the analysis of human DNA. He completed his career as the chairman and chief executive officer of LabCorp, one of the world’s largest operators of clinical laboratories.