Re:20 years ago, Apple bought NeXT
by flomo on Wednesday December 21, 2016 @12:05AM
(#13226914)
UNIX is an open standard with a certification program, and Linux certainly tries to follow the standard.
The only real reason that a Linux distribution hasn't been UNIX-certified is because RedHat and IBM found there was very little marketing value in calling it UNIX, that is, Linux is a stronger brand.
And I suspect the only reason MacOS is UNIX-certified is because they advertised it as "UNIX" and were sued by The Open Group, who owns the trademark. [1]
The only real reason that a Linux distribution hasn't been UNIX-certified is because RedHat and IBM found there was very little marketing value in calling it UNIX, that is, Linux is a stronger brand.
And I suspect the only reason MacOS is UNIX-certified is because they advertised it as "UNIX" and were sued by The Open Group, who owns the trademark. [1]
[1] https://www.cnet.com/news/apple-in-court-dispute-over-unix/