OCP

Owners and contractors protective liability (OCP) coverage was designed (1) to protect an owner who could be drawn into a suit because a contractor, hired by the owner, causes a third party's injury or damage, or (2) to protect a general contractor in similar circumstances when a third party's injury or damage is caused by a subcontractor.

This coverage is usually included in a General Liability policy and in this case provide the contractor with coverage in the event that one of his subcontractors acts gets the contractor into a lawsuit.  

This coverage can be purchased as a monoline coverage by a project owner. In this case it provides premises liability coverage for the owner on an excess basis  for the particualar contract only but the owner must hire a general contractor to perform the work. The general contractors liability policy is the primary coverage. OCP coverage is considered excess.