The High Court has ordered the disclosure of certain documents which businessman Denis O'Brien says he needs for his defamation and conspiracy action against the Red Flag Consulting public relations company.
Ms Justice Mirian O'Regan also made orders for discovery of certain documents by Mr O'Brien to Red Flag.
Mr O'Brien is suing Red Flag and a number of people who worked for it over the contents of a dossier which he says Red Flag prepared on him in an effort to injure his commercial and business interests.
He is also suing businessman Declan Ganley who Mr O'Brien believes commissioned Red Flag to prepare the dossier. The defendants deny the claims.
Mr O'Brien received the dossier on a USB stick which was delivered anonymously to office in Dublin in 2015.
Pending the trial, the O'Brien side sought information in the possession of Red Flag which he says shows hostility and ill-feeling by the defendants towards him. They also show there was a campaign of briefing politicians and journalists with material adverse to his (O'Brien's) interests, he claims.
The Red Flag defendants said the documentation sought was too vague and subjective and opposed the application.
Michael Cush SC, for Mr O'Brien argued there was evidence to show hostility in texts which went between one of the Red Flag defendants, Karl Brophy, and former TD Colm Keaveney.
These texts related to asking Mr Keaveney to set up an allegedly clandestine meeting between former assistant secretary in the Department of Finance, Neil Ryan, and then leader of the opposition, now Taoiseach Micheál Martin.
It is claimed this meeting was to discuss Mr O'Brien's private banking affairs in particular in relation to his loans and the sale to him of utility services company Siteserv by IRBC which Mr O'Brien says was overseen by Mr Ryan before it went into special liquidation.
Mr Cush said these texts show the allegation of hostility towards his client was more than just a bare assertion.
Michael Collins SC, for the Red Flag defendants, said the principle on which the O'Brien side relied was that a plaintiff cannot make a bare assertion of wrongdoing and then seek to build a case on it on the basis of discovery of documents.
Merely "pointing to a load of texts" which refer to Mr O'Brien's affairs in general terms did not amount to particularisation of an assertion of wrongdoing, he said.
In her ruling, Ms Justice O'Regan said the main issue in contention was the discovery sought by Mr O'Brien in relation to certain categories of documents.
In relation to documents which showed ill feeling and hostility towards Mr O'Brien, she said they were within the gift of the O'Brien side to produce and did not require discovery.
In relation to documents connected to the alleged encouraging of disclosure of information by Mr Ryan, on the basis of communications between Mr Keaveny and Mr Brophy, the judge believed Mr O'Brien had made out a stateable claim and she granted discovery of that category.
In relation to documents showing the briefing of politicians and journalists, she believed to be overly broad in the extreme and was not appropriate for discovery.
She also ordered discovery of all documents in relation to allegations concerning Mr O'Brien's confidential banking information.
She limited the time period during which the discovery orders relate to from October 2014 to December 2015.
She granted a stay on her orders pending a possible appeal.
The judge also dealt with the Red Flag discovery application concerning documents from the O'Brien side which he says showed hostility and ill-feeling towards him and documents evidencing Red Flag's alleged briefing of politicians.
Following agreement between the sides about reformulating the wording in relation to certain documents sought, she also granted the Red Flag application.