I'm no lawyer, but I expect this means that EY is on record acknowledging his creative debt to JKR, and doing so because he thought he was legally obligated to. It seems like it would be hard to argue that MoR is fair use. This shows that the intent of the work was something the author thought was in range of her copyright, and thus not something like parody.
This makes no sense to me.
EDIT: and specifically, acknowledging the debt is more of a good thing; from one discussion:
Whether the infringer copied the original in good faith or for a commercial interest may contribute to the court's understanding of the context of the infringement.72 Any aspect of the infringer's conduct, including whether the infringer acknowledged the copyright owner or whether the infringer sought permission, can be considered.73 Acknowledgment of a source, however, does not excuse infringement when other § 107 factors are present. 74 Additionally when the second work is a parody, the parodist is neither expected to seek nor obtain the copyright holder's permission.75 Understandably, few authors would grant permission to have their character or their work mocked.76
I just looked up JKR's statements on fan fiction, and I got the impression that she would sue in case something were published for profit, or just published in some print medium (I suppose a book or magazine).
I don't think you could defend MoR as a parody with JKR's original books as the target. Some MoR chapters point out absurdities in JKR's work, but EY doesn't make it his business to lampoon the original series. Judging from the wiki page on fair use, this makes MoR a 'satire', and these fare much worse in fair use cases.
The point about acknowledging...
The new discussion thread (part 15) is here.
This is a new thread to discuss Eliezer Yudkowsky’s Harry Potter and the Methods of Rationality and anything related to it. This thread is intended for discussing chapter 82. The previous thread passed 1000 comments as of the time of this writing, and so has long passed 500. Comment in the 13th thread until you read chapter 82.
There is now a site dedicated to the story at hpmor.com, which is now the place to go to find the authors notes and all sorts of other goodies. AdeleneDawner has kept an archive of Author’s Notes. (This goes up to the notes for chapter 76, and is now not updating. The authors notes from chapter 77 onwards are on hpmor.com.)
The first 5 discussion threads are on the main page under the harry_potter tag. Threads 6 and on (including this one) are in the discussion section using its separate tag system. Also: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13.
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