Condition subsequent

A condition subsequent gives immediate effect to a contract or obligation, but provides that it will cease or be reversed if an uncertain future event occurs. Swiss obligations law allows such conditions within the limits of legality, possibility and compatibility with the transaction. Until the event, the obligation is effective and must be performed. If the condition occurs, the agreed consequences follow, which may include termination, restitution or loss of a right. It differs from a fixed end date because the event may never happen.