Is the polygon pictured below compliant with the OGC Simple Feature standard?
There are two interior boundaries that share a segment so intuitively I would say it is not but I have not been able to find any confirmation in the documentation (in the 1.2.1 version, polygon is described on pages 26-28).
There are "rules that define a valid polygon" and I don't see there anything that would exclude polygons whose interior boundaries touch, but I also don't understand why, based on those rules, are some of the example polygons in Figure 12 invalid so I must be missing something.