Rocketdyne
The Rocketdyne Division was founded by North American Aviation (NAA) in 1955, and was later part of Rockwell International (1967-1996) and Boeing (1996-2005). In 2005, the Rocketdyne Division was sold to United Technologies Corporation, becoming Pratt & Whitney Rocketdyne as part of Pratt & Whitney. In 2013, Pratt & Whitney Rocketdyne was sold to GenCorp, which merged it with Aerojet to form Aerojet Rocketdyne.
Acoustic Research
In 1967, Acoustic Research was bought by Teledyne, Inc., and for the next 22 years it continued development and operations in Cambridge as Teledyne Acoustic Research. Technological breakthroughs in this period included the high-current amplifier. When purchased by Teledyne, AR was the world's second largest supplier of branded loudspeakers. Although Acoustic Research had continued in product development, by 1989 AR had dropped to fifth place worldwide, and Teledyne sold the company to their major competitor, Jensen Electronics. In 1996, Jensen, including AR, was sold to Recoton Audio Corporation.