I believe your first link is still version 20. Here is version 21: https://tools.ietf.org/html/draft-ietf-websec-key-pinning-21 https://tools.ietf.org/html/draf

I believe your first link is still version 20. Here is version 21: https://tools.ietf.org/html/draft-ietf-websec-key-pinning-21 https://tools.ietf.org/html/draft-ietf-websec-key-pinning-21 . Also, your second link point to a 404. There is a 'g' missing in the link to Mozilla Wiki: https://wiki.mozilla.org/SecurityEngineering/Public_Key_Pinning https://wiki.mozilla.org/SecurityEngineering/Public_Key_Pinn... . And https://tack.io https://tack.io doesn't respond for me whereas http://tack.io http://tack.io does.