451 is a great status code, right up there with 418.
[1] https://en.wikipedia.org/wiki/Fahrenheit_451_(disambiguation...
It's legitimate in the same way that '451: we want to load up our site with so much javascript your computer catches fire and burns your house down, but that's illegal in your jurisdiction so this site is Unavailable for Legal Reasons' is.
To me 451 is like 404 (nothing here) and 410 (was something here but now there isn't) - it's a further progression/specificity to 'was/sort of is something here but it's not presently available for legal reasons'.
Common obvious one is DMCA takedown notices, but it might also be an injunction, or even accidentally published while still under embargo - or deliberately to prime SEO (not advice) - or NDA, etc.
Project Guttenberg in Germany (and The Pirate Bay in the USA, I think) would be 451.
It’s not something to be proud of, but it is something I am sympathetic about. Modern laws (not just GDPR) are long and the language is often hard to understand.
I believe that laws must be simple enough to comprehend, or else they will not be comprehended and thus will be violated even by people who want to follow them — the phrase would be better if it was “ignorance of the law cannot be an excuse”, because that works both ways.
It's an approximate and somewhat mythical value, popularised by Ray Bradbury's novel. Actual ignition point varies bu 100+ °F. Experience this past year with sourdough baking --- on parchment paper at 290°C (550°F) --- shows that though the paper browns, it does not combust. (Possibly affected by thermal mass / moisture of bread loaf.)
https://slate.com/technology/2012/06/ray-bradbury-death-does...
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