Bill Gates, DOS and CP/M

Bob Zeidman asks and answers … Did Bill Gates Steal the Heart of DOS?:

Zeidman's analysis is a really good read – I won't spoil it for you.

The history of the computer industry is filled with fascinating tales of riches that appear to practically fall from the sky.

Along with stories of riches won, there are stories of opportunities missed. Take that of Ronald Wayne, who cofounded Apple Computer with Steve Wozniak and Steve Jobs but sold his shares for just US $2300. And John Atanasoff, who proudly showed his digital computer design to John Mauchly—who later codesigned the Eniac, often defined as the first electronic computer, without credit to Atanasoff.

But by far the most famous story of missed fame and fortune is that of Gary Kildall. A pioneer in computer operating systems, Kildall wrote Control Program for Microcomputers (CP/M), the operating system used on many of the early hobbyist personal computers, such as the MITS Altair 8800, the IMSAI 8080, and the Osborne 1, before IBM introduced its own machine, the PC. Kildall could have virtually owned the personal computer operating system business, had he sold that system to IBM. He didn’t. Why is a matter of speculation, mundane gossip, and urban legend. We’ll get to that.

Bill Gates at Microsoft, however, did sell an operating system to IBM—and reaped then-unimaginable rewards. A cloud of speculation has hung over that part of the story as well. The big question: Was the operating system Gates sold to IBM his to sell? Or was a key part of it stolen from Kildall?

Microsoft has stated that its hands were clean. Kildall maintained that QDOS, and subsequently MS-DOS, had been directly copied from CP/M and thus infringed on his copyright. But until now there’s been no way to conduct a reliable examination of the software itself, to look inside MS-DOS for the fingerprints of CP/M, and settle the issue once and for all.