Key legal question
Whether the earlier cantonal judgment in another case created res judicata on the settlement's validity against A.
Extracted holding
No. The earlier judgment bound only its parties and did not have third-party res judicata effect against A, who was not a party there.
Extracted reasoning
Material res judicata generally binds only parties and their successors. The earlier dispositive part did not decide the settlement vis-à-vis A, and the reasons alone had no binding effect in a different dispute.