The nature of the key: not “person or persons unknown”
In an attempt to escape the consequences of his inability to sign a message using Satoshi’s public PGP key Dr Wright made two separate assertions regarding the technical capability of the key:
First, he suggested that “the PGP key is not specific to any individual but to a server at Vistomail” (Wright4 [105] {E/4/35}).
Second, he said that the key was “not a signing key” (Wright11 [242] {CSW/1/46}) and “Only for encrypting, never for signing” ({Day7/143:10}).
However, as the Developers submitted, the content of the key itself shows both assertions are wrong:
The key expressly identifies the user ID as “Satoshi Nakamoto <satoshin@gmx.com>” {G/6/50}.
The sigclass of the primary key is clearly identified as “0x13” {G/6/50}. That sigclass is defined in the OpenPGP Message Format as follows “Positive certification of a User ID and Public-Key packet. The issuer of this certification has done substantial verification of the claim of identity” {L2/202.1/20}. It ties the key directly to the satoshin@gmx.com address, not to “a server at Vistomail” or “person or persons unknown”. Dr Wright had to admit this association: {Day8/167:8}.
The algorithm used in the generation of the primary key is clearly identified as “algo 17” {{G/6/50} – see next to “signature packet”}. Algo 17 is a DSA (i.e. a Digital Signature Algorithm) {L2/202.1/62}, that is to say an algorithm for digital signatures. It is not an encryption algorithm. So the primary key was not an encryption key: it was specifically for signing. Again, Dr Wright had to admit this at {Day8/166:10-11}.
The key flags for the primary key (noted against the reference “hashed subpkt 27 len 1” at {G/6/50}) are shown as “03”. Key flags are binary flags {see OpenPGP Message Format at {L2/202.1/33} at [5.2.3.21]}. 03 corresponds to 11 in binary and marks the key as being “used to certify other keys” (0x01, or 01 in binary) and “to sign data” (0x02, or 10 in binary) {see OpenPGP Message Format at {L2/202.1/34} top of page}.
In short, I am satisfied that every element of Dr Wright’s factual and technical explanation of Satoshi’s PGP key was wrong. The Developers submitted that one inference to be drawn from that shortcoming in his evidence, and from the sharp change in that evidence following disclosure of Mr Malmi’s emails, is that Dr Wright was telling these lies to avoid the inference to be drawn from his failure to sign a message using Satoshi’s PGP key. I agree. However, Dr Wright’s erroneous understanding of Satoshi’s PGP key is yet a further indicator that he cannot be Satoshi Nakamoto.