This dataset merges Google's V3 Open Buildings, Microsoft's GlobalMLFootprints, and OpenStreetMap building footprints. It contains 2,705,459,584 footprints and is divided into 200 partitions. Each footprint is labelled with its respective source, either Google, Microsoft, or OpenStreetMap. It can be accessed in cloud-native geospatial formats such as GeoParquet, FlatGeobuf and PMTiles.