Felt like picking your brains with this question. Imagine the scenario: An author is browsing through fanfictions of his/her work for fun when he/she stumbles upon a fanfiction that he/she really likes. The plot is compelling enough that, by God, he/she could take it and write a complete novel about it as either a sequel or a spin-off of the existing series. He/she could take it and develop it, make it stronger. Question: Even though the characters, the setting, the lore, etc. all belong to the author, the plot he/she is reading about kind of...doesn't. It was created by a fan. Would the author have legal right to take that plot created by the fan and use it for his/her own without permission? And to set the control on this scenario, the author found this on FanFiction.Net and the fan who wrote it put up the obligatory disclaimer saying he/she doesn't own any of the author's works, etc. The fan isn't trying to pass any of it as his/her own original piece. That was a thought that just occurred to me now. We've all heard of plagiarism when the fan rips off of the author's work, can the reverse also be true? If so, is there a way for said fan/writer of fanfiction to 'fight back' as it were? Thoughts?