There have been Linux distributions certified as Unix in the past.
When people say “Unix”, they usually could care less about certification.
I’d still say that BSDs are Unix and Linux isn’t due to, say, kernels of Solaris and FreeBSD having some traces of similar architecture, while Linux is a completely different thing.
Linux distros aren’t unix. Common misconception. Mac OS is certified in fact.
There have been Linux distributions certified as Unix in the past.
When people say “Unix”, they usually could care less about certification.
I’d still say that BSDs are Unix and Linux isn’t due to, say, kernels of Solaris and FreeBSD having some traces of similar architecture, while Linux is a completely different thing.