Detect Overlap Across Layer

• The tool has no dialog. It acts on the layers selected in the Contents pane, so select every layer to be compared before clicking.
• Overlaps found between the layers are written to an error layer named Overlap Across Layer Errors.
• Cross-layer overlap is usually a different question from within-layer overlap. A parcel layer must not overlap itself, but a building layer legitimately sits inside a parcel layer. Use this tool where two layers describe the same kind of thing — two communes' parcel sets meeting at a shared border, or a new survey against the existing cadastre.
• For faults within a single layer, use Detect Overlap/Gap, which also finds gaps.
• No geodatabase topology is created, so this works on shapefiles and on data outside a feature dataset. The trade-off is that there is no error inspector and no way to mark an overlap as an accepted exception — for that, use Boundary Overlap.

1. In the Contents pane, select the polygon layers to compare — hold Ctrl to select more than one.
2. On the KGA Toolbox tab, in the Data Management group, open the Feature menu and click Detect Overlap Across Layer.
3. Wait for the run to finish. The Overlap Across Layer Errors layer is added to the map.
4. Work through the reported overlaps, deciding in each case which layer holds the correct geometry.

Requires an active KGA Toolbox license. The tool validates the license before running.