Medco Health Solutions, Inc. was an American Pharmacy Benefits Management (PBM) company which served more than 65 million people, before it was ultimately acquired by Express Scripts in April 2012. Medco provided pharmacy services for private and public employers, health plans, labor unions, government agencies, and individuals served by Medicare Part D Prescription Drug Plans. Medco was a member of the S&P 500 and ranked number 34 on the 2011 Fortune 500 list, with 2011 revenues of more than $70 billion.