Copyright
What a can of worms. This is about the US. I have no idea where you are and even less of an idea how copyright works where you are. I am not a lawyer, not do I play one on TV. If I get some fact wrong, please use the contact me form. If you disagree with me, I don’t care.
Pretty much everything is copyright. Have an original idea of some sort and write it down, that’s copyrighted. Nothing else you have to do.
Nothing is set until the end of the court case. Just cause someone lost a copyright case does not mean they will not sue you. In the US anybody can sue anybody. If they lost a case it might be harder for them, but they can try. For years Warner, I think, claimed they had a copyright on happy birthday. If a restaurant wanted to sing it for a customer Warner said they had to pay. Lots of places either paid Warner or used a different song. Then someone said I’m going to use it, sue me. Warner did. The court case decided that Warner did not own the copyright to the song. Now everybody can sing the song. Warner could still sue, but you could point to the court case and say they don’t even own the song.
You need to get a license from the copyright holder. In the license it will specify what you can do. You could get a license to print one for yourself, but if you print a bunch and sell them you could be in violation. If the only license available is for personal use, contact the seller and they may have a commercial one. On the other hand it is their property and they may not want you selling them.
Read the license. It lays out what you can and can not do. If the license does not say you can use it commercially, you can’t. There is no there a big company and they do not let anybody use the character so I should be able to use it. The IP is theres and they can do what they wish with it.
So, you have this pokemon game and you rip the pikachu asset and print it. That’s a violation. You look at the game and design your own pikachu and print it. That’s probably a violation. Nintendo has the Intellectual Property of pikachu. Just cause you did your own drawing you still stole the idea of pikachu. At trial you could try to convince the court that your yellow character with a lightning bolt for a tail is not pikachu and Nintendo could say it is. The court will decide.
That’s the law. Nintendo is probably not going to sue you if you print 3 pikachus to sell at the farmers market. Even if they do sue you it will probably start with a cease and desist letter from their lawyers. Obey what the order says and they will probably leave you alone. But, for 3 pikachus you will probably never get the letter.
Disney did send a cease and desist to a daycare center who had painted disney characters on the wall. The center took the characters down and it did not go to trial.
Yeah, but mickey is out of copyright. Not so fast. The original steamboat willie is out. The mickey we all know and bow down to has white gloves, willie does not. So the mickey you know is still in copyright. He is also a trademark of Disney and tracemarks can last forever.
On websites I see characters that are probably the IP of someone. The STL is pretty much a theft of the IP. The license on the object says you can’t copy it. I stole this and you can’t steal it from me. Just because a pikachu model is on thingaverse and the license says you can use it commercially that would not stop Nintendo from being able to sue you.
That’s the legal part. What about moral.
Moral is up to you. How do you feel about stealing something. Is it OK to steal from a large company? How large does the company have to be to make stealing OK? Does it make a difference how the company behaves? If they will not license a character is it OK to steal it then?
Public Domain
After Copyright a thing goes into the public domain. Once it does that you are free to do whatever you want with it. This can cause even more confusion. You hear that Mickey Mouse is now in the Public Domain, he kind of is. The Mickey from the original cartoon is, no white gloves and other minor stuff. Mickey from later cartoons is not. Mickey is also a trademark of the Disney company and trademarks can last forever.
Original things are automatically copyrighted when they are created. There is no way for this not to happen. The copyright owner can allow free use, but the object is still copyright. With all the extensions, you have to apply for some of these, copyright can last 70 years plus the life of the creator.
So, if is not really old it probably is not in the public domain.