The aviation regulator has agreed procedures with Aer Rianta for the transfer of commercial data to his office.
The regulator, Mr Bill Prasifka, reached a deal with the State airports authority before the hearing on information it had previously refused to release to his office.
Aer Rianta's previous refusal prompted Mr Prasifka's action in March, one month after his office was formally established.
The deal marks something of an about-turn by Aer Rianta, which previously said it had given Mr Prasifka all the information to which he was entitled. Mr Prasifka regretted the legal action was necessary but said he had no option because legislation required him to make a ruling by August 31st on the fees Aer Rianta charges to airlines which use its airports.
The determination of such fees is sensitive. Disagreement over appropriate fee levels has often prompted rows between Aer Rianta and airlines, most publicly with Ryanair.
In its submission to Mr Prasifka on charges, Ryanair said: "Costs at the Irish airports controlled by Aer Rianta have been escalating, whereas the level of service provided is unacceptably low."
Aer Lingus made similar remarks.
In its submission, Aer Rianta said its three airports - at Dublin, Cork and Shannon - should be regulated as a unit.
It added: "The determination specifying the maximum airport charges . . . should be measured in the form of the revenue yield per passenger and the determination should set an overall limit on the amount which may be levied by the airport operator by way of all airport charges at the airport."
The company also said: "The price cap level may need to be adjusted within the regulatory period to take account of the capital investment profile of the airport authority."
Recent investment programmes by Aer Rianta were criticised by Aer Lingus, which said its views were ignored when the airport company decided on such schemes.
When he took the High Court action, Mr Prasifka sought copies of Aer Rianta's general ledger accounts for 1995-2000, detailing each expense category per cost and profit centre, among several other commercial records.
