Approvato lo status code HTTP 451: non disponibile per motivi legali

451 Unavailable For Legal Reasons This status code indicates that the server is denying access to the resource as a consequence of a legal demand. The server in question might not be an origin server. This type of legal demand typically most directly affects the operations of ISPs and search engines.

via datatracker.ietf.org

Da parte dell'Internet Engineering Steering Group.