[TUHS] Were any of the commercial unixes source-available?

[Ron Natalie]

Note that most UNIX was protected by Trade Secret rather than copyright 
so there’s no statutory expiration date.

We were contractors for IBM so we had XENIX and AIX sources in our 
facility under NDAs, so I don’t believe IBM dealt with it other than 
OCO.
I did have a license for the source code for Interactive Systems IS/1 
but that was a fairly straight forward System V kernel.