I'm not a copyright expert and if you told me that Harry Potter was common domain then I'd probably be a bit surprised but wouldn't think it's crazy. The first book came out 30 years ago after all. On further research the copyright laws are way more aggressive than that (a bit too much if you ask me) but 30 years doesn't seem quick. Patents expire after 20 years.
I'm not a copyright expert and if you told me that Harry Potter was common domain then I'd probably be a bit surprised but wouldn't think it's crazy. The first book came out 30 years ago after all. On further research the copyright laws are way more aggressive than that (a bit too much if you ask me) but 30 years doesn't seem quick. Patents expire after 20 years.