On Tue, Sep 15, 2009 at 2:19 PM, wiki-lists@phizz.demon.co.uk wrote:
You can't combine a CC-BY work with a CC-BY-SA work without either imposing a SA limitation on the CC-BY work,
Which anyone can do when combining CC-By and CC-By-SA works by others.
(If you don't want people adding random limitations to your works; don't use CC-By)
or removing the SA limitation on the CC-BY-SA work.
Which only the copyright holder(s) of the BY-SA work can do.
Which is no different to that of someone combining CC-BY-NC-SA license with a CC-BY-SA license.
Not so, see above. I can't combine the NC-SA and SA works of third parties without negotiating alternative license terms; the licenses are mutually incompatible.
The limitation of BY-SA keeps the work and it's derivatives freely licensed. True— it's a limitation, but it's one that merely contravenes some of frequently anti-cooperative aspect of copyright protection.
You can look at SA works as existing in a parallel copyright universe where restrictive copyright controls do not exist. This is categorically different from the (often vague) nature of use restrictions connected with non-commercial licensing.