Questão jurídica principal
Whether the arbitral proceedings were international under the IPRG or national under the Concordat
Decisão extraída
The arbitration was international because one party was domiciled abroad when the arbitration agreement was concluded, and no valid opting-out of the IPRG was shown.
Fundamentação extraída
For Article 176 IPRG, only circumstances at the time of concluding the arbitration agreement matter. Referring only to the Concordat does not clearly exclude Chapter 12 IPRG; a valid opting-out requires an express written exclusion of the IPRG and exclusive submission to cantonal arbitration rules.