Key legal question
Whether refusal of the third-party joinder request was arbitrary under cantonal procedural law
Extracted holding
The cantonal court's refusal of joinder was defensible because the buyers' warranty claim and the seller's prospective claim against the architect did not arise from the same legal basis or same damaging event.
Extracted reasoning
The buyers sued for reduction of the sale price based on an alleged defect in the sold property; the seller's intended action against the architect would be for faulty performance of a personal service. A factual link was not enough to establish the perfect connexity required by cantonal law.