The HTTP 451 Error Code for Censorship Is Now an Internet Standard

The 451 HTTP status code is now official in the eyes of the Internet Engineering Task Force (IETF), the independent organization responsible for many of the internet’s operating standards. Now, when an internet user hits a web page that has been blocked for legal reasons (read: censorship), they may be presented with a 451 error instead of the more generic 403 “forbidden” error. This is a win for transparency. The 451 code has been on the table for two years now, having been first been put forth by software engineer Tim Bray in 2013, who was in turn inspired by a blog post by security thinker Terence Eden.