Well, the "decision" was actually the consent decree in the AT&T antitrust case, which said that AT&T couldn't go into the software business. (Note well that AT&T did not have any kind of a monopoly on computer operating systems - not then, and not ever.)
The result, though, was that Unix became available for the cost of distribution plus porting, and it was portable. It was the easy path for a ready-for-real-work non-toy operating system on new hardware.
The result, though, was that Unix became available for the cost of distribution plus porting, and it was portable. It was the easy path for a ready-for-real-work non-toy operating system on new hardware.