If V10 was formally released, then yes - I would make that argument and feel free to say it to the judge.

That said, did Caldera (and/or Nokia) officially release it or are they just 'not noticing' that it is available in the wild?

I was under the impression that the only thing official is through V7.  But all the other versions have 'leaked' and are widely available, and whoever owns that IP at this point, is not pursuing protection.   I am aware that Caldera ended up with rights of 'UNIX' - certainly through SVR5 -- and they released V1-V7 and 32V under their license (pointed too in the earlier message).  However, I am ownsnot aware of who formally owns V8-V10 (I would assume Caldera also but that IP might have stayed with Lucent then Nokia as part of that BTL IP transfer].  Also, did Nokia 'formally' release Plan9 or Inferno -- is there a document like the Caldera one?