In September 1983, Hayes purchased a license from BizComp for $2 million, which included both a circuit design as well as a description of an escape sequence to trigger it. Although the concept was generally similar to their own, the Bizcomp patent differed in two key ways; one was that the escape sequence was not pre-defined and was set by the user during the startup, and the other was that it lacked the delay that was key to the way Hetherington's design worked.