The problem is that it is literally not possible to put anything in the public domain except by waiting tens of years in many countries. CC0 is the license that offers the closest equivalent effect, but its still a license. There's not really any way to fix that except to lobby governments to make an international treaty to allow placing of artefacts into the public domain. I can't really see that ever happening, though.
If I were in the US, I think I would place the code in the public domain and then also offer a CC0 license to anybody not in the US. In that case, personally, I would offer a separate patent grant just to ensure that people can use my code without worry.
For me, I would only do that if I'm trying to make a statement about copyright itself. There are lots of good permissive software licenses around and I think it's much easier to simply pick one of them. However, I can think of a few people who specifically want to unshackle themselves from copyright and this is the closest way I know how to do it. It's a definite shame that you can't do it fully on the international stage.
I live in the USA. I'd like to put my software (https://github.com/bediger4000) in the public domain. What actions do I need to take to do this? I mean, pre-1976 you just didn't put a copyright notice on it. That was enough, it defaulted into public domain. Post-1976, it defaults to copyrighted, notice or not. What otherworldly ritual do I need to perform, or notice to put on my code, to ensure it's in the public domain? I presume it's not as easy as just telling a few people, "all that's in the public domain".
> I live in the USA. I'd like to put my software (https://github.com/bediger4000) in the public domain. What actions do I need to take to do this? [...] I presume it's not as easy as just telling a few people, "all that's in the public domain".
Well, it indeed isn't that easy. You'd have to provide some kind of fallback clause, which allows people to choose CC0 or some very liberal license (ISC, MIT) at their discretion – CC0 isn't OSI-approved and ISC/MIT has an attribution requirement, so there's once more a choice needed.
People could just believe you and use the software despite having no valid permission from the copyright holder if they're willing to take that risk and just act as if the code was in the public domain.
> I mean, pre-1976 you just didn't put a copyright notice on it. That was enough, it defaulted into public domain. Post-1976, it defaults to copyrighted, notice or not. What otherworldly ritual do I need to perform, or notice to put on my code, to ensure it's in the public domain?
You still need to perform an otherworldly ritual even if you have pre-1976 code. This is because even if you've failed to acquire copyright in the U.S., you still have completely valid copyright in states where copyright was already automatic at the time and where international private law refers to the law of the state for which IP protection is sought.
Yes, beefhash is correct (posting underneath to emphasise it :-)) Just one quick clarification if it's not obvious. If you don't care about other people and just want to put your code in the public domain the US (and you are in the US), a statement to that effect is enough. However, people outside the US will not be able to safely use your code. Someday if you change your mind, you can sue them. So if you care about those people you need to choose an appropriate license to offer them.
There is a good example of this that came up recently. Jason Rohrer wrote the game One Hour One Life and put it in the public domain. An unrelated group wanted to offer the game on mobile and in other markets (notably Japan). They specifically asked for his permission to do that. He agreed. As far as I know, that's enough. So it doesn't have to be complicated -- it's just a PITA for others to keep asking for permission if you don't give them a license up front.
If I were in the US, I think I would place the code in the public domain and then also offer a CC0 license to anybody not in the US. In that case, personally, I would offer a separate patent grant just to ensure that people can use my code without worry.
For me, I would only do that if I'm trying to make a statement about copyright itself. There are lots of good permissive software licenses around and I think it's much easier to simply pick one of them. However, I can think of a few people who specifically want to unshackle themselves from copyright and this is the closest way I know how to do it. It's a definite shame that you can't do it fully on the international stage.