I presume that the question relates to (verbose) index requests on the keyservers, as a standard get request for the key will not provide any data calculated by the keyserver. In this index the keyserver displays the 32 bit keyid, but uses 64 bit keyid for internal reference (including hyperlinks from the vindex). The reason for the latter and not using full fingerprint is that this is what is used as reference for OpenPGP packets in RFC4880 (i.e the full fingerprint isn't available without calculating it). In the RFC4880bis IETF working group (for the V5 key format), it is being discussed an amendment to use full fingerprint also for the internal protocol references. For the keyservers the question of the returned value is mostly moot to begin with; the reason for this is that keyservers are themselves not trusted entitites in the ecosystem, and for this reason does not verify cryptographic material to begin with. The key material in OpenPGP is based on an object based security model and needs to be verified by the client. The client will also need to verify the identity information of the key, at which point one of (i) fingerprint of the key will be used for a direct out of band validation; or (ii) a Certificate Authority already trusted (ownertrust) by the client has signed the key. If you want to meet to discuss this, i'll be at OpenPGP.conf i Cologne this September, I will hold a session there Friday 9th. Alternatively I'm available as K_F on FreeNode (in e.g #sks) or by email on UIDs in 94CB AFDD 3034 5109 5618 35AA 0B7F 8B60 E3ED FAE3