The companies did not provide financial information regarding the transaction in their joint statement.
David Dacquino, CEO at VT, said his company will continue to provide life-cycle support to its customers.
VT provides engineering and logistics provider to Defense Department customers and was a wholly-owned subsidiary of British engineering services firm Babcock International Group Plc.
Jonathan F. Boucher, a managing principal at The Jordan Company, said VT holds a base of prime contracts with the U.S. Army and Navy.
In March, Quest Software Inc. (NASDAQ: QSFT) announced it agreed to a $2 billion buyout offer from affiliates of a private equity firm.