A technique for checking a layout design of an integrated circuit is disclosed. The technique has application to converting the design of a circuit from schematic to layout form. Instances where multiple pwell isolation tanks are coupled to the same node and where one or more pwell isolation tanks are shorted to a substrate are detected. Node breakers are inserted in the layout between pwell isolation tanks coupled to the same node and between the substrate and isolated pwell tanks coupled to the substrate. The node breakers are inserted in the circuit schematic as well to satisfy a layout versus schematic comparison. Inserting the node breakers highlights circuit component groupings as well as which tanks contain certain elements, if any. This allows designers to make a conscious decision as to the location and groupings of elements in a layout design.