[cc-licenses] Share-alike != Copyleft ?
gmaxwell at gmail.com
Mon Feb 12 10:32:34 EST 2007
On 2/12/07, Terry Hancock <hancock at anansispaceworks.com> wrote:
> that a person who puts music under a By-SA license would not be
> concerned if the music is used with a movie released under a different
> (but still "free") license.
> Don't know if the copyright laws would allow that, though.
They would likely be concerned if the different but still free license
was a weaker copyleft than the license they used. There is no point in
having a strong license if by some license slight of hand a downstream
user can switch to a weaker license, since downstream folks who want
to circumvent the stronger terms will do exactly that if the option
This is the conceptual flaw in the compatibility approach currently
taken in the cc-by-sa-3.0 draft: any work protected by a license in
the pool of licenses compatible with cc-by-sa-3.0 receives protection
only as strong as the weakest license in the pool.
This might be acceptable if the most interesting failure mode of a
free content license was to be too restrictive. But because license
restrictions can be fixed after the fact (by issuing new licenses)
while excessive permission can not be fixed except for new
works/derivatives, the too restrictive case is not the one we should
More information about the cc-licenses