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

[Ed Avis]

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.)

-- 
Ed Avis <eda at waniasset.com>