A method of integrated circuit (IC) design, an IC design system and computer program product therefore, e.g., for L3GO designs. Special case cells are cells that represent specialized, process dependent components and are provided as dual representation cells with an internal view and external view. The external view is high level abstract representation that includes access pins, boundary and possible blocking shapes/layers and optionally, parameterizations. Each external view includes cell to cell spacing rules and connecting and blocking/keepout rules for placement and routing. The internal representation or, internal view includes regular shapes forming cell components and defining cell construction details and are ground rule clean by construction or verified by simulation or hardware.