At the time it’s purchased, Nashville-based Envoy Corp. processes more than one billion health care claims for doctors, hospitals and insurance companies annually. Quintiles, the nation’s largest provider of drug trials and market research for drug manufacturers, pays $1.7 billion in stocks.

Less than two years later, Healtheon/WebMD will buy the Envoy unit away from Quintiles for stock and cash totaling $2.68 billion. This acquisition creates the largest electronic processor of medical claims in the world.