More rationale to support “leaked” versus “hacked” here:
The Prison Planet / Small Dead Animals link contains a plausible explanation until he gets to the “procmail” server method of gathering the emails.
He’s right about the file structure though, a point that I’ve made several times - the “mail files” are not really “email files”. They are “text” files that have been processed from “email files”. This article posits the theory that the leaker wrote a procmail script to cull the mail boxes of the five main “players.”
Possible. Not likely. The time frame is too long. They span 13 years.
Much more likely - they were archived via a mail archive system. Organizations that are subject to FOI requests generally keep such a system in order to maintain compliance with the law. These systems are easily searchable if you have access to the system.
Sort of points in the same direction. A leak not a hack. Except that the circle of people with access to the “archive” system is likely to be a much smaller, and raises additional questions about the makeup and intent of what I believe is a painstakingly researched “presentation” not a “hack” and not a random “leak”.