An insurer’s decision whether to defend a lawsuit against its insured can be a critical issue involving tens of thousands, if not millions, of dollars for Wisconsin companies who are sued. The Wisconsin Supreme Court recently refused to join the national trend that allows insureds to use information not contained in the plaintiff’s complaint to prove that their insurer owes them a defense. Wisconsin thus remains one of the minority of states in which courts are to look only at the “four corners” of the plaintiff’s complaint when deciding whether the lawsuit raises a claim that the insurer must defend.