Curbs on business-method claims would be a dramatic about-face, because it was the Federal Circuit itself that introduced such patents with its 1998 decision in the so-called State Street Bank case, approving a patent on a way of pooling mutual-fund assets.
对商业方法权利要求的限制将是一个戏剧性的转变,因为正是联邦巡回法院本身在1998年所谓的道富银行案的裁决中引入了此类专利,批准了一项关于汇集共同基金资产的方法的专利。
该分句由 "because" 引导,整体解释主句中 "would be a dramatic about-face" 的原因:正是联邦巡回上诉法院自己在 1998 年的判决中引入了这类专利。本层是标准原因状语从句,内部采用了强调句 "it was...that..." 结构来突出 "the Federal Circuit itself",但强调句本身是一种修辞手法而非独立从句类型,因此整体仍归类为原因状语从句。