This case relates to a lawsuit against the Wikimedia Foundation (amonsgt others) for defamation due to users' comments on the Foundation's projects. It was dismissed under citing Section 230 of the Communications Decency Act, which states that operators of "interactive computer services" (such as Wikipedia) cannot be held liable for users' comments.
See other related documents at https://www.eff.org/cases/bauer-v-glatzer
