[OSM-legal-talk] Exception in Open DataLicense/Community Guidelines for temporary file

[Tobias Knerr]

Rob Myers wrote:
> On 01/07/11 09:43, Tobias Knerr wrote:
>>
>> The only motivation for data SA I can somewhat understand is to open up
>> data that can be contributed back to OSM.
> 
> Sharealike is meant to guarantee that the individual users of the
> produced work have the same freedom to work with the data as the person
> who produced it did.

I suppose you mean that they get access to the producers own, up-to-then
proprietary, data?

If no data except publicly available databases under ODbL (such as OSM)
or an ODbL-compatible license (such as SRTM) was used to create the
derivative database, and subsequently the product, then individual users
already *have* the same freedom as the producer. They, like the
producer, can use these original, publicly available databases.

And this will likely be the case for a vast majority of OSM-based
products, if current uses of OSM are any indication. ODbL would be a lot
less cumbersome if we could limit the share alike requirement to those
derivative databases that contain unique data, i.e. are *not* calculated
from public, ODbL compatible, data sources.

> Any gifts to the *project* that result from this freedom are a side-effect.

You are right, share alike can work well even if no data ever flows back
to the project. I shouldn't have neglected that aspect. But like the OSM
community, other data users benefit primarily when they gain access to
unique data that was not publicly available before.

-- Tobias Knerr