[Commons-l] Requirements for a strong copyleft license

[Erik Moeller]

(This is a posting to multiple lists.)

As you've probably read, the Wikimedia Foundation has agreed in
principle to support an update of Wikipedia content from the GFDL to
CC-BY-SA, pending a community approval of such a migration. The FSF
and Creative Commons are supporting us to make this transition
possible.

One open issue is the way both the GFDL and CC-BY-SA deal with
embedded media files like images, sounds, and videos. The FSF
interprets the GFDL so that e.g. a photograph embedded into an article
would require the article to be "copyleft" under the GFDL; Creative
Commons does not interpret CC-BY-SA in this fashion (at least
according to some public statements).

The actual clauses are very similar, however, and I believe what is
really needed is a license that gives authors the choice of "strong
copyleft" for embedded media: the work into which the media are
embedded (whether either work is text, sound, film, a rich media mix,
or whatever) should be licensed under a copyleft license.

Wikimedia could then allow contributors of multimedia to choose this
license, and to change files under the GFDL (as opposed to text) to
it.