A Tolkien scholar writes about how he fought off a lawsuit from the Tolkien Estate:
I decided to stop feeling sorry for myself and put my research skills to work on my defense. Unfortunately, the case law was sparse. The only similar case I found was The Estate of S. Morgenstern v. William Goldman over the latter’s abridged version of The Princess Bride. It was settled out of court. There was also Lemony Snicket’s lawsuit against Daniel Handler over Lemony Snicket: The Unauthorized Autobiography, though the court ruled that a pseudonym may not sue his own author, no matter how delightfully wicked and meta that would be.