[OSM-talk] OpenStreetMap Isn't All That Open, Let's Change That and Drop Share-Alike

Robert Whittaker (OSM lists) robert.whittaker+osm at gmail.com
Fri Mar 14 13:37:39 UTC 2014

On 14 March 2014 12:01, Martin Raifer <tyr.asd at gmail.com> wrote:
> OSM having a share-alike licence enabled us to incorporate (and otherwise
> use) all kinds of open data sets, which may be licensed PD/CC0, CC-BY,
> CC-BY-SA or ODbL. (A lot of open government data in the EU is released under
> CC-BY or even share-alike.)
> If OSM would switch to something more "liberal", we would cut us off from
> potential source material: If we were going to "CC-BY" our database, we
> couldn't use CC-BY-SA and ODbL material any more, and if we were going all
> the way to "CC0", anything other than PD/CC0 would be a no-go.

As I understand it, we can't import things under CC-By-SA at the
moment anyway, because the ODbL is incompatible.

But there is a very valid point there, that it's not just a matter of
asking contributors to agree to change the license, we'd need to
review all the imported data to check whether or not the licence it
was imported under is compatible with whatever license we're wanting
to change to. To this end Ithink it's somewhat unfortunate that
OSMF/LWG haven't taken a firmer line on the use of third-party data
(not just classical "imports", but other manual uses of sources) to
ensure that the sources and licences they're used under are properly

A change to anything more liberal than either CC-By or ODC-By (the
attribution-only version of ODbL) would cut out most attribution
requiring imports -- crucially, this would cause vast amounts of
damage in the UK, where mappers have been using "OS OpenData" from the
National Mapping Agency to enhance OSM in various ways.

As for whether share-alike is a good thing, I would note that the
"contribute back" argument probably hasn't helped us all that much so
far -- but I think that's as much down to potential data users being
slow to accept the benefits of open data. Yes, some potential users
are being put off as a result, but I think in time positions may
change, and data owners may well come round to accepting the benefits
of open data. Also, it's not entirely clear whether allowing more
lberal uses would actually benefit the project that much.
(Particularly not if we didn't insist on attribution.) What
"share-alike" certainly does do is to stop companies just ripping off
our data and not giving anything back to the community.
Philosophically and practically, I think this is a very good thing.

Overall, I can see that "share-alike" may be currently holding back
some potential users, but it is also helping us by preventing
"crowd-serfing". Since corporate and government acceptance of opendata
is currently still in its infancy, I think it would be premature to
switch to a more liberal licence at this stage. We should wait to see
how things develop, as the OpenData movement gains further traction,
and the quality of OSM relative to other offerings increases.


Robert Whittaker

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