Denis O'Brien obtained the injunction to stop RTÉ from reporting details of his personal finances and relationship with former Anglo Irish Bank.
Last week, a judge granted permission for the media to report details about Mr O'Brien's finances made under privilege in the Dáil (parliament).
RTÉ lawyers said as a result there was no need for the injunction to remain.
The media mogul's fortune is estimated to be around £5bn.
Following the granting of the injunction, the purchase of one of Mr O'Brien's companies was discussed in the Dáil.
The comments were made by TD Catherine Murphy under privilege.
She said Mr O'Brien owed the former Anglo Irish Bank, now the nationalised Irish Bank Resolution Corporation (IBRC), upwards of 500m euro (£362m).
Ms Murphy, an independent left-wing TD, said Mr O'Brien was attempting to pay loans back at an interest rate of just over 1%, when it was arguable that the correct rate should be over 7%.
In response to her comments, lawyers for RTÉ and the Irish Times returned to the high court to seek clarity over whether her remarks could be reported in light of the injunction.
A judge told the media organisations that he never intended nor could he order any interference with what a TD may say under privilege in the Dáil.
The application by RTÉ to have the injunction discharged relates to a planned broadcast regarding certain information regarding Mr O'Brien's relationship with IBRC.
Lawyers for Mr O'Brien said they accepted that following comments made by the Sinn Féin TD Pearse Doherty in the Dáil on Tuesday evening, there was nothing in the proposed RTÉ script that had been injuncted that warranted further restraint.
The lawyer added that as far as he was concerned, the script in its entirety could be published, as a result of events that had happened outside the courtroom.
On Tuesday, Mr Doherty gave details of what he said were documents related to Mr O'Brien's IBRC loans during a debate in the Dáil.
The Sinn Féin finance spokesman said he had documents which led to questions about the way IBRC was run in the public interest.
Irish state broadcaster RTÉ is trying to get an injunction granted to Ireland's richest man discharged.