James P. Mitchell displayed a working prototype of a digital outgoing message with a taped incoming system at an Iowa State University VEISHEA engineering openhouse in April 1982. This system won a gold award from the Engineering department. In 1983, Kazuo Hashimoto received a patent for a "digital answering machine" architecture with US Patent 4,616,110. The first digital answering machine brought to the market was AT&T's Model 1337; an activity led by Trey Weaver. Mr. Hashimoto sued AT&T but quickly dropped the suit because the AT&T architecture was significantly different from his patent.