(3Com Corporation, Marlborough, MA, www.3com.com) Founded in 1979 by Ethernet pioneer Bob Metcalfe, 3Com was acquired by HP in 2010, and its products were fully merged into HP's product lines. Offering a wide variety of network adapters, hubs and related products, 3Com was a leading networking and communications hardware vendor deriving its name from "Computer, Communication and Compatibility." In 1997, 3Com and U.S. Robotics merged. Retaining the 3Com name, it created a USD $5 billion dollar company with more than 12,000 employees and was the largest merger in the history of the data networking industry. In 2000, 3Com spun off U.S. Robotics as an independent, privately held company. 3Com used to develop and support a line of network operating systems, which it discontinued in 1993. 3+Share was a DOS-based network operating system for PC and Mac clients. 3+Open was OS/2 based and supported DOS, OS/2 and Mac clients. See U.S. Robotics.