Last week, I made mention of the infamous Marion Zimmer Bradley Darkover case. I'm proud to say that my quick recitation of the popular understanding of the facts didn't really come down on one side or the other. I'm also proud to say that I have since tried to delve deeper into the matter after seeing a few "um, that's not really relevant" comments elsewhere. And when I say "elsewhere", I mean in Anna Genoese's recent posting about fanfiction, which led me to the monstrous Making Light thread (!!!750+ comments!!!), and to various legal-type links from there.
In those many, many comments, after the MZB incident got bandied about and was met with less-than-universal acceptance, Mercedes Lackey (apparently as close to the cat's mouth as we can get now that MZB has passed) provided the details of the situation. Meanwhile, Teresa Nielsen Hayden was crafting this analysis of the MZB affair. So there you have it: what really happened in the MZB case, and a good analysis of why it's representative of other things for authors to watch for rather than of how fanfiction causes problems for authors.