Companies that work with each other share insurance through adding the other company as an “additional insured” in connection with their work together. Sometimes it is not clear that the claim falls within the scope of additional-insured coverage. The New York Appellate Division recently confronted whether an insurer had a duty to defend in those circumstances, answering the question that it does. BP A.C. Corp. v. One Beacon Ins. Group, 2006 NY Slip Op. 05297 (N.Y. App. Div., 1st Dept. July 6, 2006).