Most savvy internet users should be familiar with at least a few HTTP status codes. 404, for example, is a common code that informs users when a page can’t be found, and you’ve probably come across others before, such as 403 (forbidden), 500 (internal server error), and 301 (moved permanently).
The Internet Engineering Task Force (IETF) has now come up with a new status code that will inform users when a page has been taken down or removed for legal reasons. The code, 451, will be accompanied by an error message stating that the web page is “unavailable for legal reasons.”
Any pages that display status code 451 should also include an explanation of why the page was removed for legal reasons, including who made the claim, what legislation allows them to make the claim, and who it applies to. The code can also be used by ISPs and DNS providers to identify who blocked the page, if the page wasn’t blocked by the website host itself.
