On the merits - meaning

The parties shall maintain the confidential nature of the arbitration proceedings and the arbitration award, including the hearing, except as may be necessary, to prepare for or conduct the arbitration hearing on the merits, or except as may be necessary in connection with a court application for a preliminary remedy, a judicial challenge to an award or its enforcement, or unless otherwise required by law or judicial decision. Each party agrees that it shall use its reasonable best efforts to cause its directors, officers, partners, associates, employees, affiliates and agents to abide by this confidentiality agreement.

Hi. This is part of an engagement contract. What does the bold "on the merits" mean?

Thank you.