It was recognized by the panel and appellate body that unforeseen developments must be demonstrated as a matter of fact though they are not independent conditions for the application of a safeguard measure Wto的专家组和上诉机构多次确认了这一点，即“不可预见的发展”虽然不是采取保障措施的独立条件，但其必须要作为一个事实问题得到证明。
