New York-based Veritas Capital and investment management firm Elliott Management (Mgt) have agreed to acquire healthcare software company Athenahealth Inc for $5.5 billion in cash.

The acquisition values Athenahealth at around $135 per share.

In its third-quarter, Athenahealth said its revenue was $331.4 million, an increase of 9 percent compared to the same period last year.

Athnahealth shares ended trading on Friday at $120.35. The transaction is expected to be announced on Monday.