Yes, the foundation of all software licensing is copyright law and as such all such licensing becomes null and void once it is in the public domain. However, g

Yes, the foundation of all software licensing is copyright law and as such all such licensing becomes null and void once it is in the public domain. However, given that the copyright horizon is only up to 1928 in the US, you've got a ways to go before that is even theoretically a concern. There was a window of time in which works had to be registered to have a copyright, which is where some of the later surprisingly-public-domain works come from, when the registration wasn't done or wasn't renewed properly. It's possible that some software in that era could be unregistered. However, I'm having a bit of trouble finding a good term for that era and so I can't quite look it up to see if it overlaps a period of time in which software might exist. Any help appreciated from respondants. Of course, for that to even matter, someone has to have a copy of the software to actually put into the public, and software utility without hardware to run it is pretty limited.