[OSM-talk] License plan

[Ed Avis]

MP <singularita <at> gmail.com> writes:

>>>As for the people who can't be reached/refused to accept new
>>>license - what about tagging such data with some tag like
>>>"license=cc_by_sa"

>>I don't think that would work.

>Well, if you need the data for personal use - you can use them even
>with mixed license.

If you need personal use only then Google Maps is fine.  Freely
distributable map data is the raison d'etre of OpenStreetMap.

>This would allow the remaining cc-by-sa data to be iteratively
>deleted and then redrawn under "correct" license.

That would have to be a very careful process.  Imagine that you
started with a printout of Google Maps and iteratively rubbed out
small sections and redrew them.  Even when you had redrawn the whole
thing, do you think you'd really be on a firm legal footing?

The purported reason for relicensing is to put the project on an
undeniably sound legal basis.  The only way to do that is to get
explicit permission from some contributors, and remove the
contributions of all the rest (as well as anything that depends on or
was derived from those contributions).

Obviously a flag 'this road was formerly marked as one-way, but that
tag was removed for copyright reasons' would just be a way of copying
the removed data.  So you would have to be careful when removing data
and make sure that whatever is re-added is done from scratch, by
re-tracing the satellite outlines and re-walking the streets, and
without any automatic notice 'something is missing here'.  There would
need to be reasonable checks that nobody is copying data from the
CC-BY-SA licensed set, since doing so would be very tempting.

-- 
Ed Avis <eda at waniasset.com>