Majority decision by an arbitral tribunal: voting and signatures

An arbitral tribunal does not generally have to decide unanimously. Section 604 ZPO provides for a majority of all members of a tribunal, unless the parties agreed otherwise. The vote, the chair’s role, an unjustified failure to participate and the signatures on the award can nevertheless affect the formal assessment.

Anyone receiving or preparing an award should therefore look beyond the result. The composition of the tribunal, the recorded vote and the explanation for any missing signature may matter when the award is reviewed.

This article separates a majority decision from a purely procedural order. It explains the practical checks under sections 604 and 606 ZPO and the separate costs decision under section 609 ZPO.

How section 604 ZPO determines the tribunal majority

Unless the parties agreed otherwise, every decision of a tribunal with more than one arbitrator is made by a majority of all members under section 604 ZPO. The reference point is therefore normally the full tribunal, not merely those who happen to vote.

The chair may decide alone on procedural matters if the parties or all members authorised the chair to do so. That specific power cannot automatically be extended to the merits award. The arbitration agreement and applicable rules must be read carefully.

What an unjustified failure to participate means

If one or more arbitrators fail to participate in a vote without a justified reason, the remaining arbitrators may decide without them. The required majority is still calculated from the total number of participating and non-participating members. A smaller group cannot simply replace the statutory majority.

For a vote on an award, the parties must be informed in advance that this approach is intended. For other decisions, notice of the non-participation is given afterwards. Invitations, notices, minutes and the reason for the absence should therefore be reviewed together.

What the chair may decide alone

The chair manages the tribunal but does not automatically receive an additional vote. For the merits decision, the majority of all members remains decisive unless the parties agreed otherwise. Under section 604(1) ZPO, a sole decision by the chair is possible for procedural matters only where the required authorisation exists.

The documents should show whether the issue was procedural or concerned the relief sought. This distinction prevents an organisational order from being confused with the award on the dispute.

Which signatures the arbitral award requires

Section 606(1) ZPO requires a written award signed by the arbitrator or arbitrators. Unless the parties agreed otherwise, the signatures of a majority of all tribunal members are sufficient. The chair or another arbitrator must record in the award the obstacle preventing the remaining signatures.

The signature question is separate from the voting question. An award may have the required votes but still require review if the signatures or the obstacle are not documented. Conversely, enough signatures do not cure a missing voting majority.

How a dissenting view can be documented

Section 606 ZPO addresses the written form, signatures, reasons, date, seat and service of the award. It does not create a general duty to issue a separate dissenting opinion. Whether and how an arbitrator records a separate view may depend on the parties’ agreement and the applicable rules.

The formal starting point is whether the majority decision and the award are clearly identifiable. A separate text should not be confused with a second or contradictory award. The agreed rules, minutes and served award should be read together.

Why the separate costs decision matters

When the arbitration ends, section 609 ZPO generally requires the tribunal to decide on reimbursement of costs unless the parties agreed otherwise. The tribunal exercises discretion in light of the circumstances, particularly the outcome. Reasonable costs of properly pursuing or defending the case may be included.

The costs decision is not the same as the formal question whether the voting majority and signatures satisfy sections 604 and 606 ZPO. If costs are decided in a separate award, that award must again meet the requirements of section 606.

Documents needed for a formal review

Collect the arbitration agreement, the appointment and composition of the tribunal, applicable rules, invitations, notices of votes and minutes. Add the complete award, all pages bearing signatures and proof of service.

Arrange the chronology: when was the vote held, who participated, what notice was given and when was the award served? The guide on the seat of arbitration in Austria helps identify the Austrian statutory framework. The page on preparing arbitration proceedings addresses claims and evidence.

Common questions about majority decisions in arbitration

Must an arbitral tribunal decide unanimously?

No. Under section 604 ZPO, a tribunal generally decides by a majority of all members unless the parties agreed otherwise.

Are the signatures of a majority of arbitrators enough?

Under section 606(1) ZPO they are generally sufficient unless the parties agreed otherwise, provided the award records the obstacle preventing the missing signatures.

May the chair decide the award alone?

Section 604(1) ZPO permits the chair to decide alone on procedural matters if authorised. The merits award generally requires the tribunal majority.

Next step

Contract, arbitration clause, correspondence and deadlines should be collected. It can then be assessed whether negotiation, preservation or arbitration is central.