Not everything JK pulled from is out of copyright. But generally Authors are allowed to reuse all sorts of things. Compare say Battle Royale to the Hunger Games

Not everything JK pulled from is out of copyright. But generally Authors are allowed to reuse all sorts of things. Compare say Battle Royale to the Hunger Games. Writing a story about Kids fighting to the death doesn't give you a monopoly on that storyline. See this link, lots of recent works in there. https://en.wikipedia.org/wiki/Harry_Potter_influences_and_analogues https://en.wikipedia.org/wiki/Harry_Potter_influences_and_an...