Thrifty Rent-a-Car System, Inc. (Thrifty) (plaintiff) commenced operations in 1958. On July 26, 1964, Thrifty obtained federal trademark registration for the mark “Thrifty Rent-a-Car System.” In 1967, Thrifty opened a branch in Massachusetts. Thrifty eventually became the fifth-largest car rental agency in the world, with 23 Massachusetts locations. Thrift Cars, Inc. (Thrift) (defendant) commenced operations in East Taunton, Massachusetts in 1962. Thrift was a local outfit, limited to business in Massachusetts. As of July 26, 1964, Thrift’s business was limited to East Taunton, except for sporadic rentals to other areas of the Commonwealth. In 1970, Thrift began operations in Nantucket. Even after 1970, Thrift maintained an East Taunton address and phone number, and continued to advertise in East Taunton. Thrifty sued Thrift for trademark infringement. The parties stipulated that their names were confusingly similar. The district court (1) enjoined Thrift from operating outside of East Taunton; (2) enjoined Thrift from advertising outside of East Taunton, except in those publications in which it had advertised prior to July 26, 1964; (3) enjoined Thrifty from operating in East Taunton; and (4) enjoined Thrifty from advertising in media targeted to the East Taunton area. Both parties appealed.