Exactly one year ago, the late Caldera company made most of its pre-1979 Unix code Open Source, see
http://www.tuhs.org/Archive/Caldera-license.pdf. This means that even large parts of the AT&T Unix
code are free today - explicitly made free by them. Thus they can (and will) hardly claim that anybody violates their rights concerning basic Unix concepts now.
See http://shop.sco.com/caldera/ancient.html to see the license on their own web server. But that's not really interesting because they've released all of this stuff except for System III under a BSD-style license (including advertising clause) in the meantime, as you can see at http://www.tuhs.org/Archive/Caldera-license.pdf. Another interesting link is http://unixtools.sourceforge.net/, pointing to some System V userland code released by Caldera in 2001.
Exactly one year ago, the late Caldera company made most of its pre-1979 Unix code Open Source, see http://www.tuhs.org/Archive/Caldera-license.pdf. This means that even large parts of the AT&T Unix code are free today - explicitly made free by them. Thus they can (and will) hardly claim that anybody violates their rights concerning basic Unix concepts now.