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RFC · WebStandard explained

RFC 7725: HTTP 451: Unavailable for legal reasons

Summary

RFC 7725 defines status code 451 for resources to which access is denied because of legal demands. Error codes can make social causes technically visible. Transparency about blocking is itself part of an open network infrastructure.

Ideas

  • 451 distinguishes legal blocks from technical errors.
  • Responses can name the responsible party.
  • Transparency information may link to additional sources.

Remarks

  • RFC 7725 has the status “Proposed Standard”; current errata and successor documents should also be checked.

Recommendations

  • Use 451 only for actual legal restrictions.
  • Document the legal reason and the responsible party as far as permitted.

References

Read the RFC at the RFC Editor

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