I suspect that they may be using their GPS trace database. It would be hard to prove. Traditionally, as some may know, mapping companies added "trap streets" -

I suspect that they may be using their GPS trace database. It would be hard to prove. Traditionally, as some may know, mapping companies added "trap streets" - intentional mistakes. With OpenStreetMap they should have to look at unintentional mistakes. Mistakes where the map is wrong compared with aerial imagery and with GPS traces.