Marsh & McLennan Agency L.L.C. has acquired Trion Group Inc., a large, privately held employee benefits firm.

Marsh & McLennan Agency, a unit of a brokerage subsidiary of Marsh & McLennan Companies Inc., New York (NYSE:MMC), says it bought Trion, Conshohocken, Pa., to implement a strategy that calls for using acquisitions to build a national benefits and property-casualty insurance operation.

The Trion deal is the sixth Marsh & McLennan Agency has made since November 2009, and the Trion deal has made the agency the 12th largest in the United States, the agency says.

Trion was founded in 1999 and now generates about $74 million in annual revenue from the sale of group life and disability insurance, absence management services, consulting services, benefits administration services, and related products and services, Marsh & McLennan Agency says.

The agency is not saying how much it is paying for Trion, but it says it expects Trion’s four principals — Ed Garno Jr., Ed Garno III, Dave Oberkircher and Chris Veno – and all of Trion’s employees to stay on.

- Allison Bell