These files are the last experimental history files produced under the CC BY-SA license. More recent data under the ODbL license is available here.
The full-planet-120401-final.osm.bz2 file is the last dump of data before redactions were run to remove data which could not be released under ODbL. The full-planet-120601-1150.osm.bz2 is the last dump of data available under CC BY-SA, but after the redactions were run. This means it may have less data in some areas, although many redactions were quickly re-mapped.
Licensed under the CC BY-SA 2.0
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