[OSM-legal-talk] ODBL enforcement: contract law and remedies

[Matt Amos]

On 10/28/09, Ed Avis <eda at waniasset.com> wrote:
> Matt Amos <zerebubuth at ...> writes:
>
>>let's assume some data are taken and modified and used to generate
>>tiles. the ODbL would require that the modified data are made
>>available, regardless of the license of the tiles. if the data were
>>effectively-PD then there would be no requirement to make the modified
>>data available (although i guess it would be allowable to trace the
>>tiles, subject to the ToS of the site). likewise, CC BY-SA requires
>>that the tiles are CC BY-SA, but requires nothing regarding the
>>redistribution of the data.
>
> You're right.  In a way this is like the source code requirement of
> copyleft licences for computer software.  So it's one case where
> the ODBL gives a stronger share-alike than CC-BY-SA.  (I would check,
> however, that this isn't going to slow the uptake of OSM by sites which
> want to draw their own maps showing houses for sale, etc.  They would
> not be happy having to publish that additional data because it could
> be considered a Derived Database under the ODBL.)

we had a long thread on this a couple of weeks ago (ODbL "virality"
questions) from which i think the consensus was that linking OSM data
with data from independent sources creates a collective database,
rather than a single derivative database. this is permissive enough to
allow 3rd parties to use OSM data in their sites whilst still
protecting the OSM data. in this respect it's like the LGPL more than
the GPL.

cheers,

matt