[OSM-talk] server migration update / license change

[Richard Weait]

On Thu, Apr 5, 2012 at 4:07 PM, Paul Norman <penorman at mac.com> wrote:
> If the tiles are not regenerated then they will contain elements that are
> licensed as cc by-sa only.

"Old tiles", the tiles generated at osm.org right now, are created
from a CC-By-SA data base and are CC-By-SA tiles.  No problem.

> If you mix cc by-sa data with other data, doesn't this mean that the entire
> work is only available as cc by-sa?

No.  You can, and some have, published All Rights Reserved © books
with CC-By-SA OSM map images included.  No problem there.

In the case of osm.org tiles, there is even less of a problem.
1) "Old tiles", the current ones, are ccbysa from a ccbysa data base.
That's fine.
2) "Future tiles", after the license switch is thrown, will be ccbysa
from an ODbL data base.  That's fine.
3) The Collective Work [1] of "old tiles" and "future tiles" in the
OpenLayers frame on osm.org will also be CC-By-SA.

So I don't see where there would be a licensing concern.

There IS a "mapper concern."  We'd like to keep the tiles fresh,
wouldn't we?  So updating cached tiles after any update is something
that we all like to see.  But I don't see a licensing concern here.
:-)

[1] term from CC-By-SA for combining separate works.  In this case,
each tile is a separate work.