The revamped Stratigraphic Nomenclature of the Netherlands was published in 2020. This new version came with new distribution maps for many of the stratigraphic units contained in the Stratigraphic Nomenclature. Those distribution maps were added to get a general understanding of the distribution of a unit. Since the release of the revamped website, many people have asked for the ArcGIS shapefiles of the polygons in the distribution maps. It even appears that for many stratigraphic units, the maps published here are the only ones available.
Therefore the Geological Survey of the Netherlands, part of TNO, has decided to release the shapefiles of the polygons used for the distribution maps. The files are made available as ZIP-files per stratigraphic group, and can be downloaded here.