[cc-licenses] [Foundation-l] [Commons-l] Requirements for a strong copyleft license
james at grimmelmann.net
Mon Dec 3 17:34:06 EST 2007
On Dec 3, 2007, at 3:32 PM, Terry Hancock wrote:
> This may or may not be included in the concept of copyleft as used by
> the GPL, but I think the argument that the definition of
> "derivative" or
> "copy" under copyright law constrains the extent of copyleft is false.
> Copyleft is presented not as an alternative to copyright, but rather
> an alternative to *financial compensation*. Instead of charging a fee
> for the license to use the copyrighted material, we insist on
> of use. Thus the limits are on what kind of fee can be charged for a
> copyrighted work, not what works can be copyrighted.
> So long as the use is not something which is otherwise allowed under
> "fair use" or "fair dealing" provisions of copyright law, then, you
> a license to use the work. In principle, just about any
> legally-admissible contract requirement can demanded as a condition of
> that use (you are always free not to use the work -- too harsh a set
> requirements is like charging too much money for a work).
This is right, and it provides a chance for a quick interjection on
terminology I've been meaning to make for a few days.
I would say that "weak" and "strong" copyleft are misleading terms
because there's a continuum of strength. A completely non-copyleft
license is at the weakest end. The strongest end (call it CC-SA-to-
infinity) would be something like a requirement that the licensee
agree to license everything she copyrightable she creates under the CC-
SA-to-infinity license. If she doesn't so agree, she can't use the
original CC-SA-to-infinity licensed work at all.
This conversation started out of a belief that the current version of
CC-BY-SA, as generally interpreted, is too weak, and that a strong-er
copyleft version of it is needed for Wikipedia integration. That's
led to an interesting and important discussion about what that strong-
er copyleft license would look like. We should be careful about
calling that strong-er version "the" strong copyleft version CC-BY-SA,
because there are a lot of different degrees of strength it could
take. I'm not sure there'll only ever be one possible "strong"
version of CC-BY-SA worth talking about, and I wouldn't like to end up
in a situation where we need to talk about the "strong strong
copyleft" or the "double-strong copyleft" or "beyond strong copyleft"
or "PowerThirst copyleft" or the "less strong copyleft." Especially
if something like Erik's final goal -- you can embed a CC-BY-SA+ item
in some kinds of larger works that are under free but non-copyleft
licenses -- is part of it, "strong" by itself is going to be a bit of
a misleading description.
> Of course, courts have in the past invalidated contracts on the basis
> that they make "unreasonable" or "unexpected" demands that were not
> understood by the party agreeing to the contract, and so invalidated
> contracts. So, there's probably *some* limit on copyleft. But I'm
> reasonably certain that "what could be considered a derivative under
> copyright law" is not it.
This is also true; there's a limit on how strong a strong copyleft
will be enforceable. I'd guess that sometime before that point, the
stronger copyleft actually becomes counterproductive because it deters
too many people from using it at all.
More information about the cc-licenses