>How is it possible that they can sell licenses to the code that was put into the public domain by other contributors?
"Public domain" does not mean: this has to be free, nobody can ask for money.
"Public domain" means: noone has the right to stop anyone else from doing what they want.
The same is true for things like the Mona Lisa. You can snap a photo of it (that photo may or may not be copyrightable, depends on the country, meaning you may also "steal" someone elses photo if applicable), print posters and sell them. This is possible because the intellectual property is in the public domain. It doesn't mean you have to give your posters away for free. You can even charge people to look at your photo -- disregarding the fact that noone probably would pay.
My question was the assertion of the ability of granting licenses in a place which doesn't recognize public domain. If the place doesn't recognize public domain, then in that place, the copyright of the code contributed by a user is still the users. So where does the company get the authority to license it?
Couldn't the person who put in into public domain go to the country and sue them saying the company is licensing their code? How can the company defend itself? We all know how it should go but that might not be what actually might happen.
>So where does the company get the authority to license it?
The company doesn't need any authority because anyone can "license" public domain software, just like I can sell you a star in the sky. It's a worthless piece of paper, its a gimmick and a way of making a donation to a cause you appreciate.
>Couldn't the person who put in into public domain go to the country and sue them saying the company is licensing their code?
Again, you're misunderstanding what public domain means. "The person" you mention has no right to sue anyone because the thing being discussed has been released into the public domain. Nobody owns it.
To illustrate: when you say (paraphrased); "The author could sue you for misusing what he/she put in the public domain" the logic doesn't hold, because if the author could to that it wouldn't be released into the public domain.
"Public domain" does not mean: this has to be free, nobody can ask for money.
"Public domain" means: noone has the right to stop anyone else from doing what they want.
The same is true for things like the Mona Lisa. You can snap a photo of it (that photo may or may not be copyrightable, depends on the country, meaning you may also "steal" someone elses photo if applicable), print posters and sell them. This is possible because the intellectual property is in the public domain. It doesn't mean you have to give your posters away for free. You can even charge people to look at your photo -- disregarding the fact that noone probably would pay.