[OSM-legal-talk] Licensing implications when extending POI with external metadata

[Anthony]

On Fri, Jan 21, 2011 at 3:58 AM, Joao Neto <joao.p.neto at gmail.com> wrote:
> If the OSM POI data is displayed together (i.e. in the same page or same
> screen or same map, etc.) with data and POIs from other sources, does the
> "share-alike" apply?

The question is whether the OSM POI data and the proprietary POI data
constitute "separate and independent works in themselves".  I'd say
being on the same page or same screen, in itself, is fine, but if you
mix the sources together into a single map (regardless of the
technical process used to create that map), then you must make the
map, including the underlying data, CC-BY-SA.  Until that point, I
think you're fine, so long as you keep the data in separate tables,
and probably even if you keep it in the same table with a column that
distinguishes the two.

Some people disagree with this, and feel that if the works are
combined by the end user, for instance in javascript, that everything
is okay.  Personally I think the *intent* of CC-BY-SA is not to
include such a loophole, as there is effectively no difference between
a mashup made on the server and a mashup made on the client.

Another thing to consider is that making the mashup on the client side
requires sending the data to the client in a form that is easily
copied.  And if your map is publicly available, that means it's highly
likely that someone is going to come along and extract your supposedly
proprietary data and use a loophole of their own - the fact that
factual data is largely unprotected from copying in most parts of the
world.