[OSM-talk] Survey: How to pay the OSM bill
richard at systemeD.net
Thu Jul 12 22:11:57 BST 2007
Rob Myers wrote:
> From a recent discussion on the cc-licenses list regarding the use of
> photographs as illustrations I believe that using maps as an
> illustration wouldn't require the rest of the book to be licenced
> This is because the book isn't a derivative of the map.
I agree. It's a collective work.
> (For those of you who are familiar with Free Software licences; BY-SA
> works more like the LGPL than the GPL.)
I do disagree with you here, though.
The LGPL is pretty clever because it enforces a separation between
two domains: the "application", and the "library" which the
application makes use of.
CC-SA, in an OSM context, doesn't enforce any separation between the
"map", and the "data" which the map makes use of. Consequently if you
use OSM data, all of your map has to be shared-alike - not just the
Actually the GPL is a fair comparison with CC-SA. CC-SA has the
concept of a collective work. So, to be fair, does the GPL. That's
because the GPL is a software licence, and the equivalent of a
collective work is "different files on the same filesystem". The GPL
doesn't insist that, because you have one GPLed program, all software
on your hard disc has to be GPLed; similarly, CC-SA doesn't insist
that, because one page of your book is a CC-SA map, every other page
has to be CC-SAed.
The main difference is that the GPL (and LGPL) require you to publish
the source, and CC-SA doesn't. But for our purposes as agitators for
free geodata, a "publish the source" requirement wouldn't be a bad
LGPL for (geo)data would be a real step forward.
Follow-ups to the neglected legal-talk list? As its maintainer I feel
some paternal affection for the poor little thing.
(memo to self: do not join in licence debates after 3.5 pints of cider)
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