[OSM-legal-talk] CC-BY-SA for source data, other license for rendered derivatives

Richard Fairhurst richard at systemeD.net
Wed Feb 28 11:24:54 GMT 2007


Etienne wrote:

> On 2/28/07, Richard Fairhurst <richard at systemed.net> wrote:
>> What I'd say is that it is certainly possible to come up with a
>> licence where the _illustration_ needn't be copyleft, but the source
>> code would still be copyleft.
>
> I think this idea is worth investigating.  I think what you are saying
> is that we need some way of making the rendered version publishable
> under some other license but requiring the corresponding source data
> of that rendering to be CC-BY-SA.
>
> I can see some interesting issues with this, but it seems to better
> describe how most people would like to see the data licensed.  It
> would maximize the use of OSM data while still protecting the source.

Yes, spot on. It would also mean that additions to the data could be  
fed back into OSM, which CC-SA doesn't require.

The key, I think, is that we require that the geodata in the "map"  
(rendered version, derived work, call it what you will) is still  
licensed under our terms. So:

> 2) What would be the status of data that is digitised from a rendered
> image?  Especially if the quality of the resulting data was a near
> match to the original source data.

The geodata is copyright OSM Contributors, and licensed according to  
our terms - no matter how you extract it.

> 4) What form of license would be appropriate for the rendered
> versions?  What restrictions would necessarily be required.

You would be required to impose the same licence requirements on the  
geodata. So you could sell (say) a proprietary cycle map as long as  
the underlying geodata was still available under OSM's terms.

> 1) What constitutes a rendered version?  Is an SVG file a rendered
> version or just a transformation of the source data?  How would this
> be defined in a license?

That's actually defined by local law, not by our licence. In the UK,  
CDPA 1988 I.I.1.9.3 refers ("in the case of a work which is  
computer-generated...").

> 3) When OSM source data is combined with other data to create a
> rendered version,  if the  rendered version is then published, should
> there be a requirement to publish the other data under CC-BY-SA, or
> can it remain unpublished?

This is the crux, I think.

What I'm suggesting here, as a way forward, is a "data copyleft"  
licence. That would require that the other data were published as  
ShareAlike/copyleft.

Allowing it to remain unpublished is little different from full PD (or  
PD-with-attribution). Personally I'd prefer this, but other  
contributors such as Oliver disagree strongly. I think more OSM  
contributors, on balance, might be satisfied with a "data copyleft"  
licence than with any of the alternatives.

cheers
Richard





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