In 1980, a company called Franklin Computer produced a clone of the Apple II called the Franklin Ace, designed to run the same software. They copied almost every detail of the Apple II, including all of its ROM based software and all the documentation, and sold it at a lower price than Apple. We even found a place in the manual where they forgot to change “Apple” to “Ace”. Apple was infuriated, and sued Franklin. They eventually won, and forced Franklin to withdraw the Ace from the market.

Even though Apple won the case, it was pretty scary for a while, and it wasn’t clear until the end that the judge would rule in Apple’s favor – Franklin argued that they had a right to copy the Apple II ROMs, since it was just a “functional mechanism” necessary for software compatibility. We anticipated that someone might try a similar trick with the Macintosh someday. If they were clever enough (which Franklin wasn’t), they could disguise the code (say by systematically permuting some registers) so it wouldn’t look that similar at the binary level. We thought that we better take some precautions.


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All you had to do to invoke it is enter the debugger and type a 6 digit hexadecimal address followed by a “G”, which meant execute the routine at that address. We demoed it for Steve and he liked it. We were kind of hoping someone would copy the ROM just so we could show off our foresight.
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