[cc-licenses] [Foundation-l] Requirements for a strong copyleft license

Platonides Platonides at gmail.com
Wed Dec 5 16:32:51 EST 2007

Daniel Kinzler wrote:
> Brianna Laugher 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".
> No it isn't, there is one important difference: derivative work, i.e. modified
> versions. Again, compare to the LGPL: modified versions must be distributed
> under the same license (though larger works which use/incorporate clearly
> demarked LGPL components do not). This is not true for CC-BY: if i make a
> derivative of a CC-BY work, I have to attribute the author, but i can license my
> version under whatever conditions i like. That's not weak copyleft, that's no
> copyleft at all.

I like that concaption. However, as simple it is to differenciate when 
it's a text/image issue, what happens when the modified version is also 
an image, but breader. Eg. the virgin case. Is that a composition of 
your photo with the text and background (it would have been composed in 
layers) or simply a derivative work?

The LGPL doesn't either define the difference.

Daniel Kinzler wrote:
> something like "CC-BY-SA/commons-mod".
Don't call it so. People would start confusing it with Cc-by-sa. Maybe 
CC-BY-LSA (Less Share-Alike) following LGPL sample?

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