The US health insurer, WellPoint, is buying its rival Amerigroup for $4.46bn (£2.87bn). The move is a major bet on the expansion of the US government's Medicaid health plans for the country's poor.
The companies unveiled the deal a week and a half after the US Supreme Court upheld President Barack Obama's healthcare law, which will extend health coverage to the more than 30 million uninsured Americans.
Industry analysts expect the deal to kick off a new wave of acquisitions among insurers. Combined, WellPoint and Amerigroup will serve more than 4.5 million beneficiaries of state-sponsored healthcare plans.