Talk:Share-alike

Latest comment: 9 years ago by KTucker in topic Merge into copyleft
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Merge into Viral license edit

Viral license is just a perjorative term for a share-alike license, so it makes sense to me that they should be merged. --Sanglorian (talk) 06:41, 26 October 2012 (UTC)Reply

Merge into copyleft? edit

Should this article be merged with Copyleft? 80.177.208.41 21:25, 14 October 2005 (UTC)Reply

I think it should be. I've never heard "share-alike" used outside of CC licenses and it seems just to be a synonym for copyleft. I'm putting a merge tag on the article. Nathan J. Yoder 22:49, 22 October 2005 (UTC)Reply
I disagree. Someone asked me to make some maps I created, and liscences under {gfdl} up on the creative commons. So I tagged them with the creative commons share-alike liscence. Then I did a little looking around. I had assumed that the two liscenses would be sufficiently compatible that they would be no confusion over releasing the images under both. What I found was that it was not that clear. And I am grateful that there is a separate article on share-alike.
What I found is that the debian-legal group recommends debian contributors not use cc-sa liscense, at all. They don't consider those liscenses "free".
My initial understanding is that when I first put the {gfdl} on my images I released a bunch of rights. I don't regret that. And that is a good thing, because, my understanding is, the release of those rights was irrevocable. The rights released under the cc-sa liscenses are also irrevocable.
The articles point to one another, at the appropriate points, correct? So, if there are really significant differences, as the debian-legal people claim, a merge would result in more confusion, and more work for the editors, than leaving them separate. I don't see any benefit in doing so. -- Geo Swan 15:15, 30 October 2005 (UTC)Reply
The term “copyleft” is not applicable on non-free licenses such as the CC-BY-SA-NC. -- Sloyment 08:14, 9 January 2006 (UTC)Reply
How I see it: the term “share-alike” defines a type of license, it is "merely" аn adjective which describes on which terms a work would be shared. Copyleft on the other hand could represent a special mechanism with whom you assure that a work maintains a specific license or copyright. Copyleft is, as its article says, a play on the word, but I would call it a way, a mechanism, maybe even an ideology. I believe that karatekas would use the term "DO" for this. It looks to me that that it can be used as an adjective defining the property of copyright. Anyway, as I understand the terminology: a license could be share-alike, and not conform to the idea of copyleft, and thus not be a copyleft license. If this makes any sense. :-) Biblbroks 01:28, 11 June 2006 (UTC)Reply
I agree this should be merged into copyleft. That copyleft is sometimes called "share-alike" should then be mentioned in the intro of copyleft. --Gronky (talk) 10:01, 1 April 2008 (UTC)Reply

Are Share-alike images legal on Wikipedia? edit

Anyone know for sure? Thanks! - Richfife 23:56, 3 August 2007 (UTC)Reply

Yes and No. But to answer your question, yes. Timeshift 17:11, 12 September 2007 (UTC)Reply

Individual licenses deserve separate articles edit

The license tree makes sense as a way to describe how licenses involve a series of options. However many projects, including Wikipedia, license their work under CC-SA and do not use CC-NC-SA. The current articles available about CC licenses (this one, which talks about 'share-alike' but is largely devoted to the CC notion of it, and Creative Commons licenses) are quite confusing for someone who simply wants to understand what a CC-SA license means.

Each license that is in widespread use deserves its own article to make its description completely clear and free of this confusion. SJ+ 19:06, 18 April 2011 (UTC)Reply

CC SA edit

Don't forget this one: CC SA 1.0 - the abbreviation CC SA is ambiguous - include the BY - K (talk) 00:41, 6 March 2012 (UTC)Reply

Transitioning to include non-Creative Commons licences edit

Hi folks,

I'm going to change this article so that it discusses all public licences with reciprocal licensing terms, not just the two Creative Commons ShareAlike licences. This is consistent with modern usage (see, for example, the Open Data Handbook: http://opendatahandbook.org/en/glossary.html#term-share-alike-license).

Why? Mainly because a lot of non-free, libre and open licences on Wikipedia are being described as copyleft. However, there is no other article to point them to instead of copyleft, so I'd like to point them here. I would use 'reciprocal licences', but unlike 'share-alike' 'reciprocal' in popular usage refers exclusively to copyleft licences. --Sanglorian (talk) 18:28, 5 March 2012 (UTC)Reply

Is "reciprocal" appropriate under Copyleft? edit

Just wondering? I think it has non-free associations? - Kim Tucker (talk) 10:34, 12 March 2012 (UTC)Reply

Good question, Kim. I think reciprocal in its standard use is libre; Microsoft does have a 'Limited Reciprocal License' but typically 'reciprocal' is synonymous with copyleft. To remove ambiguity, we could use 'reciprocal libre' instead? --Sanglorian (talk) 11:52, 12 March 2012 (UTC)Reply
How about "libre share-alike"? - Kim Tucker (talk) 13:01, 12 March 2012 (UTC)Reply
Done :) --Sanglorian (talk) 15:01, 13 March 2012 (UTC)Reply

History of Creative Commons ShareAlike Versions edit

Missing: ShareAlike 1.0. I think this retired licence is worthy of mention. --Kim Tucker (talk) 08:35, 2 May 2013 (UTC)Reply

Wrong statement edit

I deleted following wrong statement. The link used to verify this is dead.

Although CC Attribution-ShareAlike qualifies as copyleft because it is free content, CC Attribution-NonCommercial-ShareAlike is non-free and therefore not copyleft.[1][2]

Bye. -- 87.151.25.249 (talk) 15:48, 15 November 2012 (UTC)Reply

Merge into copyleft edit

"Share Alike" is the name that Creative Commons uses for their copyleft licences.

Their description of "Share Alike" says [1] that the effect is "that future users are not able to add new restrictions to a derivative of your work".

That's copyleft, just with a different name.

This merge should have been done years ago, but there were three objections which. Rereading that thread (it's the second thread on this page), the objections don't actually contain any reasons not to merge. I'd clarify by noting that:

  • GFDL and CC-by-sa being incompatible has nothing to do with being copyleft or share alike, the problem is caused by differences of implementation details in the legal texts. The unfortunate reality is that almost all copyleft (or "Share Alike") licences are incompatible with each other. It's very difficult to write a new copyleft licence that doesn't contain anything which conflicts with the "no adding restrictions" clause of the existing copyleft licences.
  • CC-BY-SA-NC being judged non-free by Stallman doesn't prevent it from being a copyleft licence. The goal of copyleft is to keep a work free, and the CC folk (and a substantial portion of CC users) view their NC licences as being free. The disagreement is over a separate issue (namely, do non-commercial clauses make an artistic work non-free?).
  • Lastly, someone said that copyleft is a movement as well as a licence style, but that's not accurate. The free software movement and the free culture movement are movements, with philosophies, activists and supporters. A portion of each advocate copyleft, but there is no distinct "copyleft movement" (or "Share Alike movement").

This is why "Share Alike" is only discussed in terms of Creative Commons. It doesn't exist as a concept, it only exists as a local term for what is essentially copyleft. Can we merge this into copyleft? I don't mind doing the work. Gronky (talk) 10:48, 10 May 2013 (UTC)Reply

My understanding is that "copyleft" imples freedom in the sense of the Free/Libre software definition[3], and that the concept is generalisable beyond software (e.g. free cultural works, libre knowledge, ...). The ShareAlike in CC BY-SA is copyleft because it is freedom that is perpetuated via this licence. The ShareAlike in CC BY-NC-SA would not be copyleft as it perpetuates a restriction on use. So, it is not true to say that Share Alike is "copyleft, just with a different name.". - Kim Tucker (talk) 23:31, 11 May 2013 (UTC).Reply
Copyleft implies a general idea of freedom for users and redistribution, but it isn't tied tightly to any particular definition. For software, even FSF doesn't say it's tied to their definition. For libre knowledge, what definition would it be tied to? And for culture, who says the Definition of Free Cultural Works is the definition, and what body authoritatively rules on whether something fits the definition? Indeed, Richard Stallman even endorsed commercial restrictions on cultural works: "I'm proposing that there should be copyright covering commercial distribution and permitting only verbatim redistribution non-commercially".
So my first point would be that although CC by-sa-nc fails FSF's freedom tests for software, that doesn't give a definitive result. CC by-sa-nc contains a general intent on allowing redistribution and giving freedoms to users, and it fits Stallman's freedom test for cultural goods.
An example is the GNU GFDL. Some people (notably Debian) disagree that it's free, but I haven't seen anyone claiming it isn't copyleft. (On this page, a group of Debian developers argue that GFDL is non-free but they say "As a copyleft license...".)
My second point would be that the topics "copyleft" and "copyleft licences" are not the same thing. The former is a concept, the latter is a judgement on a licence as a whole.
In this respect, the Share-alike issue is similar to that of the NASA Open Source Agreement. It has a copyleft clause (section A of OBLIGATIONS) which is very similar to GPLv2, and the licence would be free except that a later section contains a half sentence (possibly a drafting error) which only allows adding modifications that are your "original creation", so you can't merge this code with free code written by others. Now, if someone showed you just the section A of OBLIGATIONS, you would say it's a copyleft clause. Does it stop being a copyleft clause when you put it into a licence which has a freedom problem?
So it would be hard to decide if CC by-sa-nc and NASA OSA would have a place in List of copyleft licences, but that doesn't change that both contain copyleft clauses: they use copyleft.
If merged, Share-alike should be used an an example for a section about the interaction of free and copyleft. Gronky (talk) 01:32, 13 May 2013 (UTC)Reply
Strong agreement that this should be merged, for all the reasons you stated, Gronky. Would be happy to help with drafting/editing as necessary.
KTucker, I disagree that copyleft implies freedom in the FSF sense. FSF conflates the two, but the common usage does not. See, e.g., Black's Law Dictionary ("software license that allows users to modify or incorporate open-source code into larger programs on the condition that the software containing the source code is publicly distributed without restrictions") or the common substitution of "reciprocal" for "copyleft", neither of which contain connotations of freedom. LuisVilla (talk) 18:10, 7 July 2013 (UTC)Reply
I'm reminded today also that the Open Source Initiative's FAQ entry on copyleft also does not refer to or make the distinction Kim is trying to make; it says "'Copyleft' refers to licenses that allow derivative works but require them to use the same license as the original work" and then goes on to an extended answer in the same vein. LuisVilla (talk) 04:55, 9 July 2013 (UTC)Reply
As a final note on the topic, I note that the FSF itself refers to share-alike as a copyleft, both in GFDL 1.3 Sec. 11 ("'CC-BY-SA' means the Creative Commons Attribution-Share Alike 3.0 license ... as well as future copyleft versions of that license") and in the licenses FAQ. LuisVilla (talk) 21:16, 10 July 2013 (UTC)Reply

Do (merge or not) whatever you think serves users of Wikipedia best in terms of clarity. "Share-alike" (brought to prominence by the Creative Commons) was inspired by copyleft which is deemed as one of Richard Stallman's cleverest ideas in the world of free software.

Perhaps one thing to mention (or just think about :-) is that the Creative Commons community tends to describe ShareAlike in terms of not adding restrictions (the community includes many lawyers concerned with "property"), e.g.

The advantage of this license [BY-SA] is that future users are not able to add new restrictions to a derivative of your work ...[4]

while the FSF describes copyleft in terms of perpetuating the core freedoms.

Copyleft is a general method for making a program (or other work) free, and requiring all modified and extended versions of the program to be free as well.[5]

This distinction in emphasis of perspective (owner vs user) is what permits the Creative Commons to use ShareAlike to qualify both libre (BY-SA) and non-libre (BY NC-SA) licences.

Certainly within the free software and certain free culture communities one will see or hear the term "copyleft licence" as implicitly meaning a libre copyleft licence. --K (talk) 17:01, 24 December 2014 (UTC)Reply


  1. ^ "NonCommercial Sharealike is not Copyleft".
  2. ^ Archived version.
  3. ^ External references: free software and copyleft
  4. ^ https://wiki.creativecommons.org/Share_Alike
  5. ^ https://www.gnu.org/copyleft/

Let's go with the merge? edit

So there was one negative reply (Kim Tucker), and I hope the replies address the points raised. The points raised by Kim should also be kept in mind so that we can clarify them in the merged article.

Given the above replies, do any objections remain? Any other questions or things to discuss, or should we roll up our sleaves and get it done? Gronky (talk) 07:59, 9 December 2014 (UTC)Reply

Happy to help out however I can, but have never done a merge before, so would be grateful to watch/learn from someone who has. —Luis (talk) 17:02, 9 December 2014 (UTC)Reply
Oh, and, while we're at it, do we nuke viral license? —Luis (talk) 18:10, 9 December 2014 (UTC)Reply