A Maryland appellate court ruled that an insurer is obligated to defend an additional insured for claims arising, in whole or in part, for the actions of the named insured. The case is James G. Davis Constr. Corp. v. Erie Ins. Exch., 126 A.3d 753 (Md. App. 2015). 

James G. Davis Construction (Davis) worked as the general contractor on a residential construction project in the District of Columbia. Davis hired Tricon Construction (Tricon) as a subcontractor to work on the HVAC in the house. The subcontract between Davis and Tricon, required Tricon to purchase an insurance policy that would also insure Davis for claims arising from Tricon's negligence. 

The Certificate and the Policy