The Commercial Court is expected to rule later this morning on whether Apple's €850 million data centre project in Athenry Co Galway can proceed.
Three objectors asked the court to review the decision by An Bord Pleanála in August of last year to grant permission for the project.
Apple first announced plans to construct the data centre on a greenfield site at Derrydonnell Woods near Athenry in February 2015.
Construction of the first phase promised to generate 300 temporary jobs, with 100 permanent staff required to run it.
The following September, Galway County Council gave permission for it to proceed subject to conditions, but that decision was subsequently appealed to An Bord Pleanála.
Following oral hearings the planning authority confirmed the permission in August of last year.
However, three objectors subsequently asked the fast-track Commercial Court division of the High Court to review the decision.
Among their arguments was that the planning permission was invalid because the board failed to carry out a proper environmental impact assessment of the proposed development.
Later this morning Mr Justice McDermott will give his decision in the case.