[Commons-l] [Foundation-l] Requirements for a strong copyleft license

[Bryan Tong Minh]

On Dec 3, 2007 8:38 AM, Brianna Laugher <brianna.laugher at gmail.com> wrote:
>
> After rereading the CC-BY legal code it does appear you (and others
> who made this point) are correct, and I was quite mistaken about the
> strength of the CC-BY license.
> http://creativecommons.org/licenses/by/3.0/legalcode
> "You may Distribute or Publicly Perform the Work only under the terms
> of this License."
>
> Indeed it seems CC-BY is already the "weak copyleft" I was thinking
> CC-BY-SA is... CC-BY is much stronger than I realised. I thought CC-BY
> just meant "include a byline with my name".
>
> I am probably not the only one who had this impression, because the
> Wikimedia Commons summary as it stands is deeply misleading.
> http://commons.wikimedia.org/wiki/Template:Cc-by-3.0
>
> How embarrassing.
>
It's not deeply misleading, it's just too short. It should probably
say "In short: you are free to distribute and modify the file as long
as you attribute its author(s) or licensor(s) and add a copy or link
to the license".

I don't think it is copyleft, because derivative works should not be
under the same license: "If You Distribute, or Publicly Perform the
Work or any Adaptations or Collections, You must, unless a request has
been made pursuant to Section 4(a), keep intact all copyright notices
for the Work and provide, reasonable to the medium or means "

Bryan