I'm no layer, either. But in my way of reading a derived work has to be dual-licenced since both licences claim that the derived work has to be under the respective licence. So, you cannot derive a work from a GFDL-licenced original without GFDL-licencing the derivation. Of, course, the same counts for the sa-licence. -- Hansm 05:30, 2003 Nov 4 (PST)
No, I'm pretty sure that's not the case. When you do dual licenses, you offer the user either the GFDL, or the by-sa, at their discretion. You're not offering a mash-up of both licenses, but a choice between them. Dual-licensed works have to be under one or the other, not both. Here's the appropriate phrasing from the GFDL, section 4:
You may copy and distribute a Modified Version of the Document [...], provided that you release the Modified Version under precisely this License
...and section 9:
You may not copy, modify, sublicense, or distribute the Document except as expressly provided for under this License.
In other words, "these are the rules, and these are the only rules." For the by-sa:
You may distribute, publicly display, publicly perform, or publicly digitally perform a Derivative Work only under the terms of this License
I guess you could possibly write your own license text that made an exception to the license that ensures that all derivative works are dual licensed. After all, Linux and other GPL'd software have additional addenda to the GPL -- but if I were you I'd seek a lawyer's help to do that. I'm already out of my league with the one-or-the-other stuff, and I don't think I could help any further with a always-both clause.
As a personal note, Hansm, I'd like to say that I really value your contributions to Wikitravel; I think they've been significant and helful. I want to make sure you feel comfortable continuing to contribute. But when it comes down to it, if you don't want to allow redistribution of your work under the by-sa license -- that is, if you don't agree to the little bit of text under the "Save page" button -- please don't post it on Wikitravel.
I'm curious, by the way: will you still be interested in dual-licensing your work if the by-sa license is changed to allow Derivative Works under the GFDL? In other words, if your Wikitravel work could be copied to Wikipedia or CapitanCook, would you be satisfied? -- Evan 05:44, 4 Nov 2003 (PST)
OK, Evan, I see what the problem with derivations seems to be. But if you are realy right, then dual-licencing doesn't make too much sense since it were in contradiction to collaborative work.
There are 2 reasons why I would like to dual-licence. One is, of course, the we live on a kind of island with the sa-licence. Yes, I realy would appreciate if our articles could be shared with other servers like Capitan Cook or Wikipedia. The GFDL is simply much more common and better known. Actualy, this would be a reason to contribute to Capitan Cook instead of Wikitravel. But there is an other reason against: Their software and structure, which is very much better here. Evan, this is a complement to you, since you realy do a great work on the organisation of Wikitravel.
The other reason is maybe none, but as I told you, I'm no lawyer at all. There was some years ago a realy ugly thing with a server called mathworld, a big collection of mathmatical papers and encyclopadial articals for free (I don't know how exactly the licence was) use. Then, the owner of the server sold a book which was a collection of articles from mathworld to a publisher. After a while, the publisher begun a copyright dispute and the server had to been closed. I don't know if this ever could happen to as-licenced works, but the GFDL seems to be more confident, simply because it's widerly spread and therefore better prooved. -- Hansm 06:56, 2003 Nov 4 (PST)
I see why you are worried about licensing Hansm. However, I have to say that the folks at Creative Commons do seem to have things pretty clearly spelled out. They are properly funded, have a proper website, and do seem to have the proper expertise behind what they have put together. I am in favour of trying new things; if no one ever does, then we can't move forward. Besides, their licenses are starting to appear all over the place for creative works like photos and music. I plan to release several of my photos using a Creative Commons license (once I get my website working again :)
As the Creative Commons site explicitly points out, the GFDL is great for documentation but does not work very well for creations of a more general or artistic nature. I think Evan's choice of a Creative Commons license is a good one for this site. I think it is more user friendly and better meets the needs of a community not necessarily rooted in technical development. I think that once the compatibility kinks get worked out, the licenses developped by Creative Commons will form an important part of the steadily growing "copyleft" idea. CL 00:34, 5 Nov 2003 (PST)
"The by-sa license and the GFDL both require that all derivative works of a Work be made under that license itself. In other words, another contributor cannot make a dual-licensed derived work."
I don't think this is correct. If the original creator licenses a work under the GFDL and by-sa, then anyone has permission to license derivatives under the GFDL, and anyone has permission to license derivatives under by-sa. I see no reason they couldn't do both. They own the changes, so they can license the changes however they want. 22.214.171.124 14:43, 21 Dec 2003 (PST)
You may not see the reason, but it's there. I think your problem is thinking of the changes as a separate work. It's not. The whole page becomes a derivative work under one of the respective licenses. The contributor owns the derivative work in toto, not just the differences.
They only have a license to make that derivative work under the terms of the license of the work they derived from. Each of the two licenses we're talking about requires that you license derived works under exactly that license. (The by-sa license may have stipulations to allow licensing under a number of similar works in future versions, but it doesn't now.)
If the work they derived from is dual-licensed, they must pick a license. Dual-licensing means one or the other, not both. --Evan 14:56, 21 Dec 2003 (PST)
This only make sense for texts. I do use a dual licensing, but only for images. And in this case, I don't see the problem. And this should be cleared in the article. Yann 16:59, 13 Feb 2004 (EST)
How are images different? They can and should be modified, just like text. I don't think there's anything text- or image-specific in either license. --Evan 05:09, 15 Feb 2004 (EST)
First I am not sure what is the problem. If I put an image under dual licensing (say GFDL and CC-SA), then what is the problem for the user? He can use and modify this image under GFDL and he can also do it (the same use or the same modification) under CC-SA, isn't? So instead of one image with two licenses, he has two images with one license each. Computer images being virtual things, where is the problem? Yann 18:24, 15 Feb 2004 (EST)1
May be this is just confusing for the user. So I have an image I want to use both for Wikitravel and Wikipedia. What should I do? If I upload the image on WIkitravel under CC-SA and then on Wikipedia under GFDL, is this not dual licensing? Yann 18:24, 15 Feb 2004 (EST)
That's exactly dual-licensing, and that's a good example. I think that images are less of a problem, since they get edited less often than text. Probably you have a good point. --Evan 11:21, 16 Feb 2004 (EST)
Umm..Using images between wikitravel & wikipedia isn't much of an issue, atleast as far as wikipedia is concerned. The CC-SA for images is considered free. I wonder if the other way round is possible. Pamri 12:47, 6 Nov 2004 (EST)
Please correct the inaccuracies on this page
The page gets the way dual licensing works badly wrong. The GFDL or CC-by-SA licenses are only authorised to offer and require you to accept those licenses but they do not prohibit you from accepting and using other licenses. So the GFDL can require that you, if you are using the GFDL license, use the GFDL license and not some other license you invent, but it can't also stop you from using any other licenses you have. That is, its scope is restricted to limiting the rights this particular license (the GFDL) grants you. That right requires a GFDL release for your derivative works and prohibits you from using the GFDL license as your permission to use any other license. You're misinterpreting the limitations on what the GFDL lets you do on the authority of the GFDL license as a restriction on what you can do if you're authorised by other licenses. Please, if you do not accept this, ask a lawyer who understands copyright law and licensing and get it right. Jamesday 15:54, 1 Dec 2004 (EST)
I don't think you're correct. The GFDL says: You may copy and distribute a Modified Version of the Document under the conditions of sections 2 and 3 above, provided that you release the Modified Version under precisely this License. by-sa says, You may distribute, publicly display, publicly perform, or publicly digitally perform a Derivative Work only under the terms of this License. "Precisely this License" and "only under the terms of this License" seem extremely clear even to my layman's eye. Of course, if you're using dual-licensed works, you should talk to your lawyer before exercising any of the rights enumerated therein. I can just barely understand content licenses on their own; combining two or more puts my head in a spin. I wouldn't touch a dual-licensed work with a ten-foot pole. --Evan 01:55, 2 Dec 2004 (EST)
You're missing the key point, the context: the license only regulates the rights you get under that particular license. In each case, the only way the license authorises you to make derivative works is with exactly that license. That doesn't prevent you from having other licenses and also doing whatever they authorise. You'll also find that the licenses don't prevent you from using your fair use rights or any other rights you may have to make use of the works, even though those uses are distribution and display not in accordance with the license. 126.96.36.199 11:16, 2 Dec 2004 (EST)
I don't think you can comply with either license unless you make the derived works available under one or the other licenses exclusively. only and precisely are painfully clear wording. You simply can't comply with the restrictions of both licenses; you have to choose one or the other. It might be worthwhile to contrast the Open Software License or the Mozilla Public License, both of which are dual-licensing friendly copyleft licenses that have wording to allow you to exercise the rights granted in the license if you've made other arrangements with the copyright holder. --Evan 14:10, 2 Dec 2004 (EST)
I'm confused not by the licensing, but what the actual point of contention here is. It's clear, and I think the article states fairly clearly, that the original copyright holder has full control over their work and can license it multiple ways in any way they wish. And it's equally clear that anybody [i]else[/i] using a licensed piece of content must abide by the terms of the license. What's the issue? Jamesday, exactly what part of the article do you object to? Jpatokal 14:48, 2 Dec 2004 (EST)
The issue is errors like "In other words, another contributor cannot make a dual-licensed derived work", when in fact that is one of the things dual licensing enables. The page completely misdescribes how multiple licenses work together and attributes the disadvantages of single licensing to multiple licensing and vice-versa. That is: the description fundamentally misrepresents how multiple licensing works. Jamesday 12:28, 9 Apr 2005 (EDT)
I think it's really clear that when a person offers a work under more than one license, it's disjoint -- you can use the work under license A, or license B. If either of those licenses allows you to make dual-licensed derivative works, then you can. You can make dual-licensed derivative software under the Mozilla Public license and the GPL, for example. But the Creative Commons ShareAlike element and the GFDL are extremely limiting; neither allows dual-licensed derivative works.
You seem to have some other model for multiple licenses. Maybe you should spell it out a little more carefully. --Evan 22:48, 30 Apr 2005 (EDT)
The model is just that a multi licensed work is a work under multiple licenses, not a work under a multi-license. Therefore you never make a multi-licensed derivative work. When you make a derived work it is not under any license. Every time you distribute it you have to choose at least one of the licenses that allow that kind of distribution. Licenses do not allow you to make dual-licensed derivative works, because that is a right you already have, and a license cannot take that right away from you. However some licenses informs you of that. MPL and GPL also do not explicitly allow dual licensing.
And for the idea that just on of the licenses must allow multi-licensing, I can create the "You can make multi-licensed derivative works"-license --elgaard 11:47, 1 May 2005 (EDT)
I read the licenses the same way as jamesday. Lets take a concrete example: Someone writes article, Foo and releases it under both CC-by-SA and GFDL. I look at it say loudly, "I choose the CC-by-SA". Then I apply my changes and the result is the article FooBar1 which I publish on my home page under CC-by-SA. Then I read article Foo again and say loudly "This time I accept licence GFDL". Then I apply the same changes as before and get the result FooBar2, which I publish on my home page under GFDL. Then I realise that FooBar1 and FooBar2 are identical, replace them with a single FooBar file and update the COPYING files to say the FooBar is both under GFDL and CC-by-SA.
For both licenses I have released the derived work under precisely that same license.
But if we do not see it the same way I suggest we ask FSF and CC for clarification.
I agree with Elgaard's explanation above. Evan - would you respond? While only and precisely do mean what you think they mean, elgaard seems to have pointed out a clear way for someone to publish identical derived works under multiple licenses. Again, I look forward to your response. wikipedia:User:JesseW 02:35, 21 Mar 2005 (EST)
Sure, I'll comment: it sounds dishonest and indefensible. A single author producing the same content twice is not creating two derived works -- it's creating a single derived work. Saying, "I create these two identical works" does not make the two copies somehow two different copyrightable works. In the world of copyright, two identical things are the same thing. --Evan 07:53, 21 Mar 2005 (EST)
In the world of copyright two identical works are the same thing. However, in the world of licenses to use copyrighted works, two different licenses are two different things and you can both offer and accept any number of them. There's no problem in copyright law from having multiple license for the same work, some allowing live TV broadcast in New York, others in Boston, some in Los Angeles, others allowing video tape release and others DVD release. The DVD release license will say that it only authorizes DVD release. You can still do that video tape release if you buy a video tape license. It's completely normal license law to have multiple offers and acceptances of licenses, each of which only allows one form of onward distribution but which collectively allow many forms. It's not dishonest and indefensible for a movie maker to offer cinema screening licenses, video tape licenses and DVD licenses, nor is it dishonest and indefensible for you to accept each of those licenses. Jamesday 12:28, 9 Apr 2005 (EDT)
To me this is starting to sound like quantum physics and its duality concept. A dual licence is just that, a dual licence. The original article has been released under both licences therefore any edited article accquires both licence conditions simultaneously too because those are the conditions under which you edited it. You cannot choose which licence to abide by, you have to accept both at the same time because those are the conditions under which the original author released their unedited work for you to edit. Its like a photon or electron being a wave and a particle at the same time. Just because you look at it one way does not mean the other aspect does not exist, it is just that the uncertainty principle means that you cannot precisely confine the article to the conditions of one licence or the other but must accept it fits both licences without having any conflicts that prevents both licences fom applying to the article at the same time. If a contributor is dual licencing their work and both licences require the derivative work to be released under that licence alone, I would contend the original author is either creating a third licence that effectively prevents the work being modified because the two licences conflict or actually intending to release the content into the public domain. In some respects the original author could be saying just do what you want with it. (Note: The JDWYWWI is a valid licence concept I have seen used.) In this sort of area intent is the name of the game. -- Huttite 08:35, 21 Mar 2005 (EST)
If a work is relased under dual licenses you get to choose what license to accept. E.g. I can dual-license all the pictures I added to WikiTravel under the "pay 15 cents per copy" licence, but you can still choose only the CC license so you do not have to pay me. However a commercial publisher can choose to pay me 15 cents per copy and not publish the book under a CC-licence. The same publisher can use the same picture on his homepage or in a CC-book and not pay me for that. There is nothing dishonest in that. -- elgaard 09:49, 21 Mar 2005 (EST)
Yes. In fact, that's how companies like MySQL do it. MySQL offers at least three different licenses for the same thing: GPL, commercial and OEM. You can accept the ones you need (GPL for GPL products, commercial for non-FLOSS, OEM if that works better for a different product). All for exactly the same piece of software. Jamesday 12:28, 9 Apr 2005 (EDT)
It is also discussed here. It seems to me that most people do think that the same person can accept the same dual-licensed work under both licenses at the same time. -- elgaard 10:14, 21 Mar 2005 (EST)
For most licenses, no problem. For the CC by-sa and the GFDL, they're both exclusive licenses. Even the GPL allows you to license derived works under some other license (as long as you also make it available under the GPL, too). Not so the by-sa or the GFDL -- derived works have to be under exactly the same license. --Evan 18:48, 21 Mar 2005 (EST)
That only says what that license grants you the rights to do. It doesn't affect the rights you're granted by any other licenses you have. You can comply with each individual license (indeed, you do if you're using Windows OEM and Windows retail versions on two different computers - two licenses, different terms, both in use for the same product). So long as one works, you can do it. That is: the more licenses offered, the greater the flexibility for reusers, who can do what they want if any license applies. It's only an issue at the source place (this site), where it's possible that some contributors may not want to make reuse easy or might want to seek competitive advantage for one license provider by not allowing the use of other licenses. I don't have a lot of sympathy for anyone who wants to create competitive advantage by making reuse more difficult. Come now: we discussed this and you said you'd ask the list, thinking that would result in people saying I was wrong. The responders actually said I was right. Isn't it time to accept that and change the page? Jamesday 12:28, 9 Apr 2005 (EDT)
The CC license cannot forbid me to make a derivative work under the GFDL license (if the original was also released under GFDL), and vice versa. It is licenses not contracts. If a work is released under two licenses I can make a derivative work and release it under exatly the same two licenses.-- elgaard 21:08, 21 Mar 2005 (EST)
I think it should be that way, but it's not. And, yes, the CC by-sa license can forbid you to make a derivative work under any other license -- in fact, it does. It doesn't say, "... unless the original work is under that license." Neither does the GFDL. They are the two strictest copyleft licenses I know of. They say, "make derivative works under this license, period." You can pick one or the other, but not both. A dual license is an alternation, not a conjunction. --Evan 23:16, 21 Mar 2005 (EST)
No, If you put it under a dual license, it just means that you put it under two licenses, you do not create a new license. It is not an alteration or conjunction. -- elgaard 06:11, 22 Mar 2005 (EST)
I'd have to agree that elgaard looks correct. Each user owns the copyright on their changes, so they can license their changes however they want. Combine a dual-licensed article with a dual licensed set of changes and you have the next version, right? Really, I think everybody on here should be at least dual licensing as CC-By-SA 1.0 and 2.0, so that eventually the entire site could be under 2.0. [[Luke Stodola (aka LuminousCarpet or lbs6380), 30 April 2005
Eventually would be when everything written by any contributer today went into public domain in every country. This could be 200 years from now. I guess we could have everyone state on their User page, that everything they have contributeted in the past is at least both under CC1 and CC2. --elgaard 22:01, 30 Apr 2005 (EDT)
Luke: copyleft works because people can't just do whatever they want with "their changes". It's extremely, extremely rare that "someone's changes" are an independent work that's not derived from the previous version of the page. Because copyright gives authors the right to govern how derivative works are made, what the by-sa license says matters quite a lot with what people can do with "their changes".
I'm sorry that dual-licensing of derivative works of CC and GFDL works is impossible, but it's due to the poor wording in the licenses. If you have a problem with it, bring it up with CC and the FSF. --Evan 22:33, 30 Apr 2005 (EDT)
O.K., I've created articles such as Pisew Falls, which would be perfect for Wikitravel. The Text is GFDL and I'm made the images public domain. But, since others have made minor changes to this article, can I license it here or not? Do I or can I dual license? Since the original work was mine, do I need to dual license at all? I'm using the same ID on Wikipedia. Now why on Earth didn't my Username pop up when I first sent this? Weaponofmassinstruction
You can certainly add the Dec 8 version, which looks good. As long as you only add you own work to WikiTravel, it does not matter what licence you have released it under previously. However you have to dual licence it to allow others to put future versions under multiple licenses.
On the following forums/wikis:
it is discussed if it is possible to:
1. Realease a work under a CC-by-SA and GFDL dual license.
2. For someone else to create a derivative work of that and release it
under the same dual license.
It seems we cannot agree os this, so I hope FSF and CC can give a
somewhat authoritative answer.
And got this reply from FSF (just obfuscated my email a bit):
"Dave Turner via RT" <email@example.com>
elgaard at diku sot dk
I går 23:33:52
Sorry for the long delay.
> it is discussed if it is possible to:
> 1. Realease a work under a CC-by-SA and GFDL dual license.
> 2. For someone else to create a derivative work of that and release it
> under the same dual license.
-Dave "Novalis" Turner
GPL Compliance Engineer
Free Software Foundation
I'd be more interested in a longer response. "Yes" and "Yes" aren't really enough to convince me. --Evan 08:23, 3 May 2005 (EDT)
Then I suggest you write a question to firstname.lastname@example.org and CC that could give you an answer that would convince you. -- elgaard 08:43, 3 May 2005 (EDT)
I'm on it! (Email posted here:  ) --Evan 08:54, 3 May 2005 (EDT)
I have to say that this page is a piece of nasty anti-dual licensing and anti-FDL FUD. Whole world understands dual-licensing the way elgaard describes it, including FSF, CreativeCommons and WikiMedia.
Benevolent dictatorship is a good form of government as long as the dictators are benevolent and wise, which is unfortunately not the case of Wikitravel. --188.8.131.52 17:53, 19 Jun 2005 (EDT)
I couldn't care less about any of this (I think Evan may be logically right, but since the Law follows intent more than logic, I think he's wrong). However, please refrain from attempting to use our articles as a soapbox. That's what talk pages are for. -- Colin 18:26, 19 Jun 2005 (EDT)
And you recommend me what? Leave the misinformation to confuse readers? That's against my understanding of wiki. Sorry. --184.108.40.206 18:54, 19 Jun 2005 (EDT)
Unless you are a lawyer, you're just throwing in your opinions. This will only be resolved if either the FSF lawyers or the CC lawyers offer their opinion. I'lll be changing your input soon to something I hope will be agreeable to all. -- Colin 19:41, 19 Jun 2005 (EDT)
I assure you: I have nothing against the FDL. I don't think it's appropriate for all works (for example, computer programs, or very small works like travel guides), but I think it's been very useful for lots of people. And I'm not anti-dual-licensing either. I find dual-licensing really confusing, and I think applying multiple licenses to a work is more complicated than people imagine. But the more work that can be shared between GFDL-licensed sites and CC-licensed sites, the better.
I'd be happy to see some official statements on dual-licensing from the FSF, Creative Commons, and WikiMedia. I don't think anyone's delved very far into these issues. The best I've seen is in response to this question , which was this . The upshot: "precisely this License" in the GFDL does not mean "only this License" in the same way that the by-sa does. So, GFDL and by-sa can be dual-licensed.
I've meant to come back and clean up the article based on that. I've taken a first poke; please, feel free to add more.
Lastly: I'm sorry you're so attached to... what? Dual-licensing?? Are people really that passionate about dual-licensing?... anyways, attached to something that you try to reduce the hundreds of people who work on Wikitravel to some kind of serfdom. Nobody here labors under or for a dictator. They contribute because they want to make a Free travel guide. --Evan 08:41, 20 Jun 2005 (EDT)
Well, the article did (and to some extent still does) have a negative tone. I would like it to be more constructive. I.e. focus on how dual-licensing can improve WikiTravel. IMHO we can gain a lot from sharing especially images with other projects. Commons.wikimedia.org does a great job of handling both multiple licenses and versions of images. They show that it does not have to be so confusing. Cooperation works boths ways. If we want to others to release images under CC-by-sa 1.0, we should put some of our material under GFDL, CC-2.5, etc. I started with Image:Flakfortet2.jpg as  --elgaard 13:41, 28 Jun 2005 (EDT)
How about we just try to keep neutral on the issue? I still find the payoff not worth the confusion. --Evan 11:24, 29 Jun 2005 (EDT)