451 Unavailable For Legal Reasons

The server is denying access to the resource as a consequence of a legal demand.

The server in question may not be an origin server. This sort of legal demand typically affects the operations of ISPs and search engines more directly.

Responses using this status code SHOULD include an explanation, in the response body, of the details of the legal demand: the party making it, the applicable legislation or regulation, and what classes of person and resources it applies to. For example:

HTTP/1.1 451 Unavailable For Legal Reasons
Link: ; rel="blocked-by"
Content-Type: text/html


 Unavailable For Legal Reasons


 Unavailable For Legal Reasons
 This request may not be serviced in the Roman Province of Judea due to the Lex Julia Majestatis, which disallows access to resources hosted on servers deemed to be operated by the People's Front of Judea.

Use of the 451 status code implies neither the existence nor the nonexistence of the resource named in the request. That is to say, it is possible that if the legal demands were lifted, a request for the resource still might not be successful.

Note that in many cases clients can still access the denied resource using technical countermeasures such as a VPN or the Tor network.

A 451 response is cacheable by default; that is, unless otherwise indicated by the method definition or explicit cache controls; see RFC7234.