The OpenStreetMap project is preparing to delete data from its database on 1 April if data contributors have not agreed to licence their data under the Open Database Licence (ODbL) or assign it to the public domain. The move is the culmination of a near two-year long process to switch the licensing for the data behind the popular mapping project.

Map data was originally collected and distributed by the project under a Creative Commons CC-BY-SA licence. But the CC-BY-SA licence had a number of problems: for example it only used copyright law, leaving its data unprotected in the US, was not written for data or databases, and made mixing OpenStreetMap data with other sources difficult.

The project set about selecting a replacement licence starting discussions in 2005 and in 2009 voted to change the licence to the Open Database Licence. Since May 2010 the OpenStreetMap project has been engaged in a process to move from a Creative Commons CC-BY-SA licence to the ODbL. The final stage of the process will see the final export of the data licensed under CC-BY-SA; this will be frozen and kept available for the forseeable future, and the live database will then be exclusively licensed under ODbL.

From May 2010, submissions to the open map database have been made under the CC-BY-SA and ODbL licences, allowing the final change over to be made much more easily. 97 per cent of users have already approved the new licence. For people who use the rendered OpenStreetMap tiles, virtually nothing will change. Those tiles will still be published under the Creative Commons licence which requires that the OpenStreetMap project be credited as the source.

(djwm)