A Twitter user broadcasting "cynical and cranky" opinions and self-described research has lost his claim for journalist privilege to protect a source.
Alan Francis Davison says information from a corporate adviser was the basis of a May 2020 tweet to his 6800 followers about mining investor Tolga Kumova.
To avoid revealing that adviser's identity in defamation proceedings begun by Mr Kumova, Mr Davison claimed journalist privilege.
Mr Davison said the informant messaged him privately on Twitter before saying over the phone "I will be crucified if my name gets out".
"Don't worry. I will leave you right out of it," Mr Davison says he replied.
He also told the Federal Court his Stock Swami account was used to present "honest opinions on shares and shares promoters" and to present his own research on shares and so-called share promoters.
His Twitter bio - stating "Cynical and Cranky take on the ASX professional company manipulators, I mean operators, making a play on Retail. They can Block but they can't stop the Swamo" - was updated in 2021 to include "citizen journalist".
Mr Kumova challenged the claim, arguing whatever uncertainty there may be about what constituted a journalist, it couldn't be used to describe Mr Davison.
Justice Geoffrey Flick agreed.
"Although he may have complied with some of the standards normally expected of a 'journalist' in one of the publications made via his Twitter account, his conduct in the use of the platform viewed in its entirety strips him of that characterisation," the judge said on Monday.
"As put in oral submissions advanced on behalf of Mr Kumova, albeit now loosely and more generally expressed, Mr Davison 'cannot be a journalist one day but not the next'."
Mr Kumova's lawyer had provided screenshots showing the account's "unbalanced and non-factual tweets", personal attacks, tweets about Mr Davison's personal life or stock trade, and offensive language.
Justice Flick said Twitter feeds could sometimes constitute a "news medium" for the purposes of journalist privilege.
But it couldn't be said Stock Swami met that bar in circumstances where its self-professed purpose was to make known "cynical and cranky opinions", and where the account also published "substantial amounts of material which can in no sense be described as news", the judge said.
Mr Kumova alleges Mr Davison defamed him on six occasions between September 2019 and June 2020.
Mr Davison denies his tweets have the meanings attributed to them by Mr Kumova.
The Twitter user, whose followers numbered 5879 on Monday, also raises justification and contextual truth defences.