a ` rel="blocked-by" ` relation identifying the entity
implementing the blockage, not any other entity mandating it.

Any attempt to identify the entity ultimately responsible for the resource
being unavailable belongs in the response body, not in the ` rel="blocked-by"
` link. This includes the name of the person or organization that made a legal
demand resulting in the content's removal.

http

    
    
    HTTP/1.1 451 Unavailable For Legal Reasons
    Link: <https://spqr.example.org/legislatione>; rel="blocked-by"
    Content-Type: text/html
    
    <html>
          <head><title>Unavailable For Legal Reasons</title></head>
          <body>
                <h1>Unavailable For Legal Reasons</h1>
                <p>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.</p>
          </body>
    </html>
    

##  Specifications

Specification  
---  
[ An HTTP Status Code to Report Legal Obstacles  
#  n-451-unavailable-for-legal-reasons
](https://httpwg.org/specs/rfc7725.html#n-451-unavailable-for-legal-reasons)  
  
##  Browser compatibility

BCD tables only load in the browser  with JavaScript enabled. Enable
JavaScript to view data.

##  See also

  * [ Wikipedia: HTTP 451 ](https://en.wikipedia.org/wiki/HTTP_451)
  * [ Wikipedia: Fahrenheit 451 ](https://en.wikipedia.org/wiki/Fahrenheit_451) (which gave this status code its number) 

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