Presidential candidate Seán Gallagher received €130,000 last year in a legal settlement arising from the RTÉ Frontline programme during the 2011 presidential election campaign.
RTÉ also agreed to make a contribution to Mr Gallagher’s costs, believed to be a similar amount.
Mr Gallagher sued RTÉ because of the televised presidential debate in October 2011, when he was confronted with allegations about his fundraising activities for Fianna Fáil in the past.
The debate took place just three days before the election, and with opinion polls showing he was leading in the race. His support subsequently collapsed, and he was beaten into second place by Michael D Higgins.
The terms of the settlement between RTÉ and Mr Gallagher, reached late last year in advance of a High Court hearing of the case, were never revealed, with the broadcaster stating publicly only that it had paid the businessman "substantial damages".
Mr Gallagher’s complaint centred on the use of a tweet mentioned during the programme which purported to come from an official Twitter account of Martin McGuinness, the late Sinn Féin politician who was also running for the presidency. The tweet said that a businessman from whom Mr Gallagher had sought funds for Fianna Fáil would be coming forward.
Although the account that the tweet came from was not an official Sinn Féin account, the businessman – Hugh Morgan – did come forward subsequently.
The programme and the subsequent appearance of the businessman undermined Mr Gallagher’s attempts to distance himself from Fianna Fáil during the campaign.
As part of the settlement, RTÉ also apologised to Mr Gallagher, acknowledging that the production of the Frontline debate “fell significantly short of the standards expected by the public and required by law”.
In a statement afterwards, Mr Gallagher said his motivation in taking the case was “not just about the unfairness shown to him but also about protecting the integrity of the democratic process and ensuring that what happened to him will not be allowed to happen again”.
Revelations of the relatively modest size of Mr Gallagher’s settlement will come as a surprise in political and media circles where much larger sums were thought to have changed hands.