Trade Secret is one of the big reasons there was a preliminary ruling in the UCB/ATT lawsuit that 32V had lost its copyright protection. It had been distributed outside of AT&T to a large degree without the Trade Secret warning. It's why all the 4BSD releases are publicly available now.

Absolutely true, but there was a bit more work needed than just the preliminary ruling. In parallel, the TUHS folk were petitioning old SCO (not TSG) to release the ancient Unixes under a BSD-style license: https://www.tuhs.org/PUPS/petition.html. Eventually old SCO agreed to a BSD-style hobbyist license which cost US$100: https://web.archive.org/web/20010603053221/http://www.sco.com/offers/ancient.html. Some details of the process are here: https://www.tuhs.org/PUPS/pstatus.html.

Then a while later, Caldera (who had bought the Unix licensing from old SCO) offered their $0 license: https://www.tuhs.org/Archive/Caldera-license.pdf.

I want to give a shout out to Dion Johnson who was the driving force at old SCO that finally got them to agree to putting the ancient Unixes under a BSD-style license.

Cheers, Warren