Today’s 7th U.S. Circuit Court of Appeals case discusses the duty of a subcontractor’s insurer under an additional insured endorsement to provide a defense to a property owner and general contractor who hired the subcontractor and who were sued for negligence in failing to supervise the subcontractor’s work.The opinion addresses the rule that an insurer owes a duty to defend if the underlying complaint discloses potential coverage and does not otherwise foreclose coverage.In Scottsdale Insurance Co. v. Columbia Insurance …