The recent move to the Open Database Licence meant that a small number of users chose for their contributions not to continue within OSM. We asked everyone to help remap the affected areas ahead of the redaction process to reduce the impact and help ensure OpenStreetMap remains the best map in the world. This was a somewhat tricky process involving using various tools to locate data elements which were likely to be affected, removing those elements and then replacing them with new, preferably improved, map content.
The redaction process has now been run across the whole world. More than 99% of the data has been retained, and in most places, the difference is barely noticeable. There are, however, some areas of our map where the redaction was concentrated, in particular Poland and Australia. Though we would of course have preferred to retain this data, we do respect the original contributors’ decision, and we thank them for their past involvement in the project.
Fortunately the OSM community’s response in these areas has been magnificent and we believe we will be back to having a high-quality dataset in these areas in a short space of time. If, as an OSM mapper, you would like to help – by using aerial imagery and other sources, or ideally, from personal knowledge and survey – then please do get involved. Essentially we’re left with some new blank spots on the map, and can respond with the process we know and love. Use your favourite mapping techniques, go explore and fill in the blanks. (Note that you must not copy from CC-BY-SA datasets or map views based on the pre-redaction data; please treat this like you would any other incompatibly copyrighted map data.)
Simon Poole has set up a tool to help coordinate remapping in some particularly large areas: