Talk:Copyleft/Archive 2

BSD license = implicite copyleft?
All BSD licences require not only the attribution to the author(s) but also the list of conditions to be included (this is in contrast to the statement in the article that the BSD licences allow redistributions to be stripped-off some of their conditions; this statement should therefore be questioned as well). This, however, only makes sense if these conditions (i.e. the two to four clauses, depending on the actual BSD licence variant) remain force. To me this sounds like a variant of copyleft, since the requirement of retaining the original conditions is the main criterion of a copyleft license. However, BSD is not viral and does not require the sourcecode to be given away, but it is still comparable to the CC share-alike licences (which require the same conditions for copies and derivative work, but not for collections, and also does not require free access to source or master files etc.). So why isn't BSD officially considered copyleft? Where is the big difference?-- — Preceding unsigned comment added by SiriusB (talk • contribs) 13:45, 13 March 2012 (UTC)
 * You seem to be mis-interpreting the concept of "copyleft". Straight from the FSF: "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.", in other words, it means "copylefted" code can't be used in closed-source programs. If you modify a copylefted program and distribute copies of that, the you MUST distribute the source (among other requirements), otherwise you are violating the original license. --SF007 (talk) 14:48, 13 March 2012 (UTC)
 * Copyleft licenses require that derivative works be placed under the same license. BSD does not require that derivative works be under the same license, it is therefore not a copyleft license. CC SA requires that derivatives be placed under SA, it is therefore a copyleft license. The fact that SA does not require that collections (which are not derivatives) be placed under the same license does not prevent it being a copyleft license; the GPL doesn't cover collections either. Rob Myers (talk) 15:30, 13 March 2012 (UTC)


 * You seem to misunderstand me: As far as I interpret both the English and the German WP article, copyleft does not necessarily require the sourcecodes to be made available as well. However, Open Source is the only useful way to implement a Copyleft license to software in my opinion, but e.q. CC-BY-SA is also said to be copyleft, although it covers types of works where nothing like a "source code" does exist. I further disagree with your statement that BSD doesn't require the same license to be used for derivative work. The first two clauses require the copyright notice and the list of conditions to be retained for redistribution of copies and modified versions.
 * In my opinion, this is equivalent to a weak, non-open-souce Copyleft, because this requirement does only make sense if these conditions are still in force and not just citations. In other words, retaining the list of conditions for any redistributed modification just means that the same license has actually to be used for it (but binaries may be distributed alone). Please explain: When I retrieve a BSD-licensed code, how could I put it under a different license without violating the BSD license?


 * Additional note: The GPL does not explicitely cover collections, but as far as I understand, collections of e.g. pictures may be something like a website (e.g. Wikimedia Commons), a PowerPoint presentation or any other arrangement, where CC-BY-SA-licensed pictures are contained in a larger document, while software libraries might be an analog to such a collection in terms of the GPL, where its viral effect indeed requires even the linked software to be released under the GPL. I.e. if the content is linked by some piece of software (a HTML page, PPT or LaTeX document in case of CC pictures, or the links to a software library in case of the GPL). Therefore, the GPL appears to be much stronger than CC-BY-SA which seems to be a "light" copyleft just like the implicite copyleft I see in the BSD licenses, i.e. only relevant for the work itself but not to any "linked" content.--SiriusB (talk) 16:23, 13 March 2012 (UTC)


 * BSD licenses do not require the modifications in a modified work to be under the same license as the original work. What this mean is if you have a work A under one of the 3 BSD licenses, and then add some modifications lets call it B, then B can be under a second license (like a proprietary software license). When you distributive the new work AB, the A part will be under BSD, and the B part will be under the second license. If A had been under a copyleft license, then the combined work AB would had to be under the same license. As for copyleft, licenses like the GPL require source code to be released if you distributive the software. CC-BY-SA do not have any requirements for the release of source code which is why I suspect the author of Creative Commons (Lawrence Lessig) has officially recommended GPL for software and not CC-BY-SA. Belorn (talk) 21:51, 13 March 2012 (UTC)


 * I am thinking of the case that the modification B is not a complete additional program routine or something like that, but that it is rather a modified version of A. I.e. it contains large parts of the original A and differs from it in some parts. This is the meaning of "modification". What you mean is an additional software unit (e.g. a separate routine) or a separate patch that contains the changes. Only these can be distributed without the original BSD license, since they do not contain anything the author of A has written. But this is not what I am talking about. I think, we should make clear whether "retain the list of conditions" means mere citation of the original license term without any lawful meaning, of whether it means that the original license conditions are still in force. I think that only the latter case makes sense. But then it means, that the license actually does require the derivative work to be under the same license unless you are distributing them as separate patches, which, however, would still require the original code (to get a working new code) which is under the original license anyway. In other words, unless you completely rewrite the whole code there is no way to get out of touch of the original license of code A. And that, in my opinion, is at least a weak form of copyleft.--SiriusB (talk) 23:17, 13 March 2012 (UTC)


 * You're missing the point entirely. In order for a license to be considered "copyleft" it must require that the entirety of a derivative work be released under the same license. BSD-type licenses only require that the original work (not any derivative works) remain available under that license. Some people that choose to distribute under BSD-style licenses would actually take some offense to their works being identified as being "copyleft" (seeing as the intention of these licenses is to not impose additional restrictions on derivative works, only to maintain to openness of the source code as it was received). You can distribute a software Y under a closed-source license that is based on software X that was under a BSD-style license and the distributor of software Y is only liable under the BSD license that the original source for software X remain available (this could be as simple as providing a link to the initial source that they used in their software), not their derivative versions of that software, and that attribution in the license remain in place. The only license that I'm aware of the you could possibly refer to as a "weak copyleft" license is the LGPL as this allows for dynamic linking and inclusion into other software projects (which themselves may be closed source) but still does not allow for modified versions of that specific code to be distributed under anything but the LGPL and requires that the LPGL code remain open to copy, modify, and be redistributable under the LGPL. Similarly, you could distribute software under the GPL that included LGPL code but the LGPL would still apply to that specific bit of software (or any derivations thereof) while the entirety of the software project would be covered under the GPL (as they are compatible in that arrangement) and would require that distribution fall under those licenses respectively depending on exactly what parts of the software you were redistributing (either just the LGPL or the GPL or both). MerlinYoda (talk) 18:16, 10 September 2015 (UTC)

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Questionable annotation in section "Applying copyleft"
it states "(Note that the list begins from 0 as a reference to computer programming, where zero-based numbering is prevalent.)". IMHO it rather is that Freedom 0 (use the work) isn't specific to Copyleft licenses but common to all license models. Thus it's a zero'th freedom WRT Free Software/Copyleft and only mentioned for completeness. Furthermore there doesn't seem to be a citation backing the annotation as it is. BerlinSight (talk) 15:09, 26 February 2018 (UTC)

Tualha's changes
Just rewrote the beginning. The article as a whole is still rather a mess - disorganized, perticularly regarding the history, and containing plenty of redundant material. But I want to see how my new intro flies before tackling the rest.

I took out the specific examples of the "similar licenses" because one of them was the BSD License, which is not a copyleft license at all (as the article itself notes elsewhere).

Tualha 01:11, 18 Mar 2004 (UTC)

I've reworked the rework, in part because you wrote that you can't use copyrighted works without a license, which isn't a very complete summary of the situation, in part because copylefted works are copyrighted. Took the opportunity to put some of the history nearer the top so it explains the origins and intent better.

BSD isn't a copyleft license but it is a similar license, with similar objectives: making better tools available to all. It just doesn't use copyleft as one of the tools, so it's more suitable for some purposes and less suitable for others. Jamesday 21:26, 18 Apr 2004 (UTC)

copyleft characterizes free software
Copyleft is one of the key features in free software/open source licences, and is the licenses' legal framework to ensure that derivatives of the licensed work stay free/open.

Why include open source here? I think of copyleft as the key distinction between free and non-free open source, so these lines should drop the "open" references. Can an Open Source licence include copyleft features and not be free software? Even if it can, that is not typical in my experience. --NealMcB 22:48, 2004 May 24 (UTC)

copyleft anniversary in 2004?
It sounds like the 20th anniversary of copyleft is in 2004. Anyone know the date? More of the history? Commerative events? NealMcB 23:03, 2004 May 24 (UTC)

Reworking of inititial definition --Francis Schonken 07:12, 17 Aug 2004 (UTC)
I reworked the initial paragraphs of the article which define what copyleft is. While the reworking was rather intrusive (e.g. putting most of it in a new "methods for copylefting" section), I keep the original initial paragraphs here:

Copyleft is an additional (and irrevocable) provision in a copyright license that otherwise already grants certain freedoms to the licensee. These preconditional freedoms are, generally, the free unlimited use, modification and redistribution of copies of the original work. The distinctive condition to that license for being also "copyleft" is that any modified version of the work, if redistributed (thus being a derivative work), must carry the same permissions (i.e. license terms), and must be made available in a form which facilitates modification. For software, this facilitating form is considered to be a synonym to source code, pre-supposing that all necessary compilation software is also freely available.

In normal speech copyleft is also used as a pars pro toto to indicate license conditions that include all the preconditional freedoms mentioned above (often also including freedom regarding sale of media and/or of auxiliary materials, e.g. documentation, which may carry a different copyright license), together with the actual copyleft condition.

Note that copyleft generally needs to hinge to copyright law for implementing an enforcable system for derivative works to be also released with a copyleft license (so "copyleft" pre-supposes at least some framework of "copyright" law, contrary to the popular belief that copyleft wants "to do away" with copyright as a whole). Also generally copyleft implies that the names of all contributors to a work keep attached to that work. These contributors are - for reasons of protecting the copyleft mechanism by copyright law - the (pro forma) copyright holders.

So long as all of those wanting to modify the work accept the terms, one of the net effects aimed at by copyleft is to facilitate successive improvement by a wide range of contributors. Those who are unwilling or unable to accept the terms are prohibited from creating derivative works.

While what is said above somehow ties the definition of copyleft to its first recorded implementation (i.e. the GNU GPL license), a more universal and abstract definition of copyleft would be:


 * Copyleft is that property of a human creation that aims at preventing that the use, the propagation and the modification of that creation would be hindered by Intellectual Rights

In defense of the rework: the "abstract" definition is in effect more understandable than the circumstantial one with which this article used to start; I used more human-understandable words in describing how copyleft works in practice, instead of propping all that in a rather intelligible first paragraph;

First sentence (Copyleft short definition, before the start of the article)
It doesn't make any sense as it stands now. Can someone fix this?! - Ta bu shi da yu 01:15, 18 Sep 2004 (UTC)


 * It makes sense to me, but it is very heavy. Maybe it would be better to start on a lighter note, like telling it is a pun on copyright?  Per Abrahamsen 08:21, 2004 Sep 18 (UTC)


 * (Francis Schonken 09:18, 24 Sep 2004 (UTC):) I intend to make a few minor adjustments to the initial definition of copyleft. Also I will insert an unvisible HTML comment in the "edit" mode of the article inviting people to come here to discuss the definition, before changing it for the nth time. The copyleft definition of the initial paragraph looks pretty good to me as it is now, I propose only following minor adjustments:
 * "...copyleft is a pun": I think today copyleft is so much more than a pun: I propose to change to: "...copyleft started out as a pun..."
 * second sentence of first paragraph should be in my view still be a bit more neutral. I refer to the perfect article, where it is advised to make the initial definition as short and neutral as possible, while all different approaches to the initial concept can be treated further in the article (applying "space and balance" as explained in the NPOV tutorial). Well,  copyright law in general exists in order to restrict the right to make copies of a particular work IS ideological. In the case of Paganini copyright law was an IMPROVEMENT while it extended the right to make copies of a particular work. I could elaborate that as one example out of many (just ask me!), the only thing I want to say is that the use of the word restrict in the initial paragraph as it is now is tendentious (POV if you like), which makes it perfectly eligible to be treated in the "ideological debate" section, but not in the initial definition. Don't know yet exactly how to work around this in the short definition, but I'll try (and return here if it doesn't work).
 * copyleft is not a neutral term, and cannot in itself be described in the neutral pov. The best you can do is to make the pov explicit.  "The proponents of copyleft see copyright primarily as a mean to restrict copying, thus" Per Abrahamsen


 * (Francis Schonken 10:01, 24 Sep 2004 (UTC)): had to perform another adjustment: the definition was not correct, while it was a definition of "open source" (software) in general, not the definition of what is specifically added to that by copyleft (so it appeared not to be a definition of copyleft at all). Sorry guys, copyleft is a non-trivial concept: for me all the other "importance" of Wikipedia (however important!) is minor compared to producing a definition of copyleft that is as well understandable by any non-specialised person, as that it is neutral and short, and of course: undebatably correct.

I removed the reference to other kinds of IPR from the initial paragraph, it was premature (the origin of the term was certainly only about copyright, even if other people have extended it later) and slightly provocative, given that RMS does not recognise IP as a useful concept (it includes too diverse concept for his taste). I also reorganized the difinition so we only have one user. I believe copyleft is a very trivial concept, and if the first paragraph does not give that impression, it is not formulated good enough. Oh, and I made the pov on copyright explicit as FC pointed out. Per Abrahamsen 09:04, 2004 Sep 27 (UTC)

(more ideas added by Francis Schonken 10:43, 29 Sep 2004 (UTC):)
 * I corrected a small typo in the initial paragraph as it stands now ("way restrict" -> "way to restrict").
 * "copyleft (...) cannot in itself be described in the neutral pov": Well, if that were true it should not be in Wikipedia at all according to present importance guidelines. The whole Wikipedia philosophy somewhere hinges on the idea that however "POV" an idea is, it can be described in a NPOV way. Also: my point was not that a completely, and forever "Amen", NPOV short definition of copyleft is possible, only that I want to co-operate to come as near as possible to a NPOV definition of copyleft that is suitable (and relatively stable) for the present day.
 * "...given that RMS does not recognise IP as a useful concept": Richard M. Stallman deserves all possible credits for putting the idea of copyleft on the world map, but nonetheless he does not own the concept of copyleft: even if he and/or FSF would own URL's like copyleft.org or whatever, it would be entirely against Stallman's own philosophy to say he owned the concept. And even if he owned the concept, there is a distinct Wikipedia guideline telling to avoid controversy over content of wikipedia articles by considering that no faction owns the content of a wikipedia article: so even if Stallman would own the copyleft concept, he is in no way the exclusive owner of the wikipedia article describing that concept. Or, to put the same thing otherwise, using an analogy: Richard Stallman's baby has grown up, and it proves to be a rebellious teenager by now. In wikipedia the abbreviation of "Richard M. Stallman's point of view" becomes "RMS's POV", i.e., according to the NPOV tutorial, a POV that has every right to be in wikipedia, be it in balance with other POV's (if there are any).
 * Well, there are other POV's, notably:
 * Linus Torvalds' POV, e.g. describing the non-copylefted BSD not as something "bad", but as "something different from what we try to do"; and replying to someone sharing some ideas about not getting wiser from RMS's replies on a copyright issue: "I can feel the pain", further explaining he is entirely happy with GPL as a copyleft licence, but further does not want to have to do anything with RMS (if he can avoid it).
 * The Share-alike POV: which is a slightly different view on copyleft than the RMS/FSF "official" view (i.e. Creative Commons defines some things as copyleft, which would never pass as copyleft in RMS's eyes).
 * Godfried-Willem Raes' POV, who in the copyleft section of the website on the concert organisation he owns describes his idea that copyleft is the same as doing away with copyright altogether...
 * etc...
 * Frankly, I don't care all that much what RMS thinks about IP in general: I only look around me and see copyleft is used as a concept in the discussion in the European Union about the new patent law, etc... But please do note I wouldn't object a bit to have a mentioning of Stallman's view on IP in the "ideological debate" section of the article.
 * Giving my view on the question whether or not the "initial short definition" of copyleft should hint at the history of how the concept became notable: in my view this is not necessesary if a more understandable & correct definition can be given without referring to those historical issues (these historical references also kind of have a limiting effect on the short definition: all attempts I tried myself to make a definition based on this turned out to be either limiting the copyleft concept too much to software, and/or too lengthy and complicated - at least unintelligble at first reading for a not predisposed encyclopedia reader -, and/or too entangled in the ideological issues from the outset of the article, etc...). Note that there is already a fairly elaborate section about these historical issues in the article itself.
 * Giving my view on whether or not "IP" can be used in the initial definition: I think "IP" can be used in the short, initial definition of copyleft, if that is useful for a bold and neutral definition; but please do note my own propositions were to use Intellectual rights, which in wikipedia is a different article than the IPR/IP/Intellectual property article - IR refers more to the 19th century discussion when the decisions were taken whether or not to separate "copyright" from other, already existing, Intellectual rights like patents. The IR article also more hints at "unwaiverable obligations" in the European view on IP/IR related matters: this concept of "unwaiverable obligations" is useful in defining copyleft, that also starts from an "unwaiverable obligation", namely the obligation to use the same license when publishing a derivative work (IP is more concentrated on being "owner", confusing with the idea that one can do as one pleases with what one owns - which is not the case in general with IP, but that takes a lot more explaining to do).
 * Replying to "The proponents of copyleft see copyright primarily as a mean to restrict copying,...": well I am a proponent of copyleft, but I don't see copyright primarily as a means to restrict copying. I rather see traditional copyrighting as an alternate system, with its advantages and disadvantages. So do many other proponents of copyleft: e.g. when their name is Linus, or in other cases, when they don't have a problem earning money with a job that creates IP for their company (without them owning any of that IP). In fact I put considerable thinking in how it could be made possible that someone who is e.g. a computer programmer or an artist, and has an ideological problem with producing any of this kind of non-copylefted IP, could make a decent living for himself in a strict copyleft approach for everything he produces (both in intent and in legal correctness). That's when I decided to start the "commercial exploitation" subsection, now at the bottom of the copyleft article.

Intro change
I changed the first line of the intro to be something hopefully more relevent and closer to a definition of copyleft, giving some useful context before we digress in the second sentence. I did read the warning comment, but I'm hoping there is no objection to this change. Deco 02:38, 12 Nov 2004 (UTC)

New terms and symbols
Proposals for new terms and symbols for copyleft and related concepts should not appear on Wikipedia or any encyclopedia, but is work that is done elsewhere. — Preceding unsigned comment added by 132.198.104.164 (talk) 21:36, 30 November 2005 (UTC (UTC) )

earlier reference to Open Source?
I note that there was some discussion earlier on about technical differences between open source and other types of software, but as a newcomer, reading this article for the first time I was thinking "Why isn't there a link to the "Open Source" page for ages until I eventually found it in section 4.

My feeling is that there should be a mention and a link to "Open Source" much earlier in the article, somewhere in the intro, before we get into all the technical details of where the term "copyleft" comes from and what kind of things it can apply to. PaulHammond 13:57, 3 Jan 2005 (UTC)

Hi Paul,

I suppose the approach in this article has to do with:
 * "copyleft" being broader than "a type of software". Copyleft can apply to a variety of things like "art", "wikipedia content", etc... "Open Source", on the other hand, is rather used to designate software exclusively (ever seen the "source code" of an MP3?).
 * "Open Source Software" only partially overlaps with "copylefted software" (many "Open Source" licenses are not "copyleft").
 * Richard Stallman and FSF, who put copyleft as an idea on the world map, prefer speaking about "free software", explaining "free as in freedom", instead of using the term "Open Source" software (which they abhorr).
 * "Open Source" software was, I think, not all that used as a term when FSF/Richard Stallman produced their first copyleft licenses (so it is missing from section 2, describing the origin of "copyleft").
 * "Open Source Software" was particularily promoted from around the turn of the century on by Eric Raymond (and others) that wanted to abandon the idea of copyleft being the exclusive or preferable way to produce OSS.

Either way, although "Open Source" and "Copyleft" are often loosely used as synonyms, the links between the two concepts are sparser (and with more tension) than is generally perceived.

I don't know whether this answers what you were asking about, if not, just ask more (or try to improve the article where you think fit).

--Francis Schonken 01:55, 27 Jan 2005 (UTC)

PS: some of this is discussed in Free/Libre Open Source Software too - maybe that's more the article you were looking for (centers on software). Note that that article might benefit from an update too! (e.g. "Libre Software" was - for some time - a separate European episode, not bound by the Free Software movement - so "FOSS" only became "FLOSS" when the "Libre" movement was taken up too) --Francis Schonken 12:56, 31 Jan 2005 (UTC)