PGP key revocation reasons
Reason
Description
Unknown
The revocation reason does not match any of the predefined reasons.
Superseded
A new PGP key is replacing an existing PGP key.
Key Compromise
A person who is not the key subject might have discovered the private key value.
Key Retired
The PGP key is no longer used.
User ID Invalid
The user information for the PGP key is not valid.