From Maldonado v. Municipality of Barceloneta, No. 2007cv01992 (JAG) (JA) (D.P.R. Mar. 11, 2009):
On January 30, 2009, Diaz sent a ‘Facebook message’ to Febus. …
There also appears to be confusion as to the classification of the message in question. Defendants incorrectly claim the message constitutes a “blog.” Plaintiffs incorrectly claim the message constitutes an e-mail. This type of communication, a message sent on Facebook, a “social networking website,” which has not been considered by this circuit or in any other circuit to the court’s knowledge, is likely a hybrid of the two. The message in question is clearly in the latter category: messages sent to a user’s Facebook inbox are not publicly viewable. Thus, they are not in the “public domain,” where First Amendment rights might attach.