Hanover Insurance v. American Engineering Co.

KRUPANSKY, Senior Circuit Judge.

This diversity action concerned the scope of insurance coverage afforded by commercial general liability policy no. ZDL 278 88 76 (“the CGLP”) issued by appellee Hanover Insurance Company (“Hanover”) to appellant American Engineering Company (“American”). Hanover sought judicial reformation of the CGLP policy to incorporate an allegedly erroneously omitted rider (ISO Form CG 22 43 11 85) (“the rider” or “the endorsement”) which would purportedly exclude coverage for any professional negligence claim made against American. Appellant Security Insurance Company of…