Award annulled after arbitrator found jurisdiction based on invoices sent via WhatsApp

In Decision 4A_237/2026, slated for publication in the official court reporter, the Swiss Supreme Court set aside a domestic award, holding that the sole arbitrator lacked jurisdiction. The dispute concerned art sales agreed via WhatsApp, after which the seller sent PDF invoices via WhatsApp containing an arbitration clause in attached general terms and conditions (GTCs). The court held that messaging services can satisfy the text form requirement, but as there was no reference in the chat to the arbitration clause contained in attached GTCs, an intent to arbitrate could not be established.