diff --git a/cc-by-sa.tex b/cc-by-sa.tex new file mode 100644 index 0000000000000000000000000000000000000000..756a6b4d92a40ae71beaab93fd0db8c767635cbe --- /dev/null +++ b/cc-by-sa.tex @@ -0,0 +1,718 @@ +' cc-by-sa.tex -*- LaTeX -*- +% Tutorial Text for the Detailed Study and Analysis of CC-BY-SA course +% +% Copyright (C) 2014 Mike Linksvayer + +% License: CC-By-SA-4.0 + +% The copyright holders hereby grant the freedom to copy, modify, convey, +% Adapt, and/or redistribute this work under the terms of the Creative +% Commons Attribution Share Alike 4.0 International License. + +% This text is distributed in the hope that it will be useful, but +% WITHOUT ANY WARRANTY; without even the implied warranty of +% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. + +% You should have received a copy of the license with this document in +% a file called 'CC-By-SA-4.0.txt'. If not, please visit +% https://creativecommons.org/licenses/by-sa/4.0/legalcode to receive +% the license text. + +\part{Detailed Analysis of the Creative Commons Attribution-ShareAlike Licenses} + +{\parindent 0in +\tutorialpartsplit{``Detailed Analysis of the Creative Commons Attribution-ShareAlike Licenses''}{This part} is: \\ +\begin{tabbing} +Copyright \= \copyright{} 2014 \hspace{.1mm} \= \kill +Copyright \> \copyright{} 2014 \> Mike Linksvayer +\end{tabbing} + + +\vspace{.3in} + +\begin{center} +Authors of \tutorialpartsplit{``Detailed Analysis of the Creative Commons Attribution-ShareAlike Licenses''}{this part} are: \\ +Mike Linksvayer + +\vspace{.2in} + +Copy editors of this part include: \\ +You Please! + +\vspace{.2in} + + +The copyright holders of \tutorialpartsplit{``Detailed Analysis of the GNU GPL and Related Licenses''}{this part} hereby grant the freedom to copy, modify, +convey, Adapt, and/or redistribute this work under the terms of the Creative +Commons Attribution Share Alike 4.0 International License. A copy of that +license is available at +\url{https://creativecommons.org/licenses/by-sa/4.0/legalcode}. +\end{center} +} + +\bigskip + +\tutorialpartsplit{This tutorial}{This part of the tutorial} gives a +comprehensive explanation of the most popular free-as-in-freedom copyright +licenses for non-software works, the Creative Commons Attribution-ShareAlike (``CC-BY-SA'', or sometimes just +``BY-SA'') -- with an emphasis on the current version 4.0 (``CC-BY-SA-4.0''). + +Upon completion of this part of the tutorial, readers can expect +to have learned the following: + +\begin{itemize} + + \item The history and role of copyleft licenses for non-software works. + \item The differences between the GPL and CC-BY-SA, especially with respect to copyleft policy. + \item The basic differences between CC-BY-SA versions 1.0, 2.0, 2.5, and 4.0. + \item An understanding of how CC-BY-SA-4.0 implements copyleft. + \item Where to find more resources about CC-BY-SA compliance. + +\end{itemize} + +% FIXME this list should be more aggressive, but material is not yet present + +\textbf{WARNING: As of November 2014 this part is brand new, and badly needs review, expansion, error correction, and more.} + + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +% END OF ABSTRACTS SECTION +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +% START OF COURSE +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + + +\chapter{Freedom as in Free Culture, Documentation, Education...} + +Critiques of copyright's role in concentrating power over and +making culture inaccessible have existed throughout the history +of copyright. Few contemporary arguments about ``copyright in the +digital age'' have not already been made in the 1800s or before. +Though one can find the occasional ad hoc ``anti-copyright'', ``no rights +reserved'', or pro-sharing statement accompanying a publication, +use of formalized public licenses for non-software works seems to +have begun only after the birth of the free software movement and of +widespread internet access among elite populations. + +Although they have much older antecedents, contemporary movements +to create, share, and develop policy encouraging ``cultural +commons'', ``open educational resources'', ``open access +scientific publication'' and more, have all come of age in the +last 10-15 years -- after the huge impact of free software was +unmistakable. Additionally, these movements have tended to emphasize +access, with permissions corresponding to the four freedoms of +free software and the use of fully free public licenses as good +but optional. + +It's hard not to observe that it seems the free software movement +arose more or less shortly after as it became desirable (due to changes +in the computing industry and software becoming unambiguously subject +to copyright in the United States by 1983), but non-software movements +for free-as-in-freedom knowledge only arose after they became more +or less inevitable, and only begrudgingly at that. Had a free culture +``constructed commons'' movement been successful prior to the birth +of free software, the benefits to computing would have been great -- +consider the burdens of privileged access to proprietary culture for +proprietary software through DRM and other mechanisms, toll access +to computer science literature, and development of legal mechanisms +and policy through pioneering trial-and-error. + +Alas, counterfactual optimism does not change the present -- but might +embolden our visions of what freedom can be obtained and defended going +forward. Copyleft policy will surely continue to be an important and +controversial factor, so it's worth exploring the current version of +the most popular copyleft license intended for use with non-software +works, Creative Commons Attribution-ShareAlike 4.0 International +(CC-BY-SA-4.0), the focus of this tutorial. + + +\section{Free Definitions} + +When used to filter licenses, the Free Software Definition and +Open Source Definition have nearly identical results. For licenses +primarily intended for non-software works, the Definition of Free +Cultural Works and Open Definition similarly have identical results, +both with each other and with the software definitions which they +imitate. All copyleft licenses for non-software works must be +``free'' and ``open'' per these definitions. + +There are various other definitions of ``open access'', ``open +content'', and ``open educational resources'' which are more subject +to interpretation or do not firmly require the equivalent of all four +freedoms of the free software definition. While these definitions +are not pertinent to circumscribing the concept of copyleft -- which +is about enforcing all four freedoms, for everyone. But copyleft +licenses for non-software works are usually considered ``open'' +per these other definitions, if they are considered at all. + +The open access to scientific literature movement, for example, +seems to have settled into advocacy for non-copyleft free licenses +(CC-BY) on one hand, and acceptance of highly restrictive licenses +or access without other permissions on the other. This creates +practical problems: for example, nearly all scientific literature +either may not be incorporated into Wikipedia (which uses CC-BY-SA) +or may not incorporate material developed on Wikipedia -- both of +which do happen, when the licenses allow it. This tutorial is not +the place to propose solutions, but let this problem be a motivator +for encouraging more widespread understanding of copyleft policy. + + +\section{Non-software Copylefts} + +Copyleft is a compelling concept, so unsurprisingly there have been +many attempts to apply it to non-software works -- starting with use +of GPLv2 for documentation, then occasionally for other texts, and +art in various media. Although the GPL was and is perfectly usable for +any work subject to copyright, several factors were probably important +in preventing it from being the dominant copyleft outside of software: + +\begin{itemize} + + \item the GPL is clearly intended first as a software license, thus +requiring some perspective to think of applying to non-software +works; + \item the FSF's concern is software, and the organization has +not strongly advocated for using the GPL for non-software works; + \item further due +to the (now previous) importance of its hardcopy publishing business +and desire to retain the ability to take legal action against people +who might modify its statements of opinion, FSF even developed a +non-GPL copyleft license specifically for documentation, the Free +Documentation License (FDL; which ceases to be free and thus is not +a copyleft if its ``invariant sections'' and similar features are +used); + \item a large cultural gap and lack of population overlap between +free software and other movements has limited knowledge transfer and +abetted reinvention and relearning; + \item the question of what constitutes source +(``preferred form of the work for making modifications'') for many +non-software works. + +\end{itemize} + +As a result, several copyleft licenses for non-software works were +developed, even prior to the existence of Creative Commons. These +include the aforementioned FDL (1998), Design Science License (1999), +Open Publication License (1999; like the FDL it has non-free options), +Free Art License (2000), Open Game License (2000; non-free options), +EFF Open Audio License (2001), LinuxTag Green OpenMusic License (2001; +non-free options) and the QING Public License (2002). Additionally +several copyleft licenses intended for hardware designs were proposed +starting in the late 1990s if not sooner (the GPL was then and is now +also commonly used for hardware designs, as is now CC-BY-SA). + +At the end of 2002 Creative Commons launched with 11 1.0 licenses +and a public domain dedication. The 11 licenses consisted of every +non-mutually exclusive combination of at least one of the Attribution +(BY), NoDerivatives (ND), NonCommercial (NC), and ShareAlike +(SA) conditions (ND and SA are mutually exclusive; NC and ND are +non-free). Three of those licenses were free (as was the public domain +dedication), two of them copyleft: CC-SA-1.0 and CC-BY-SA-1.0. + +Creative Commons licenses with the BY condition were more popular, so the 5 +without (including CC-SA) were not included in version 2.0 of the +licenses. Although CC-SA had some advocates, all who felt +very strongly in favor of free-as-in-freedom, its incompatibility +with CC-BY-SA (meaning had CC-SA been widely used, the copyleft pool +of works would have been further fragmented) and general feeling that +Creative Commons had created too many licenses led copyleft advocates who hoped to +leverage Creative Commons to focus on CC-BY-SA. + +Creative Commons began with a small amount of funding and notoriety, but its +predecessors had almost none (FSF and EFF had both, but their entries +were not major focuses of those organizations), so Creative Commons licenses +(copyleft and non-copyleft, free and non-free) quickly came to +dominate the non-software public licensing space. The author of the +Open Publication License came to recommend using Creative Commons licenses, and the +EFF declared version 2.0 of the Open Audio License compatible with +CC-BY-SA and suggested using the latter. Still, at least one copyleft +license for ``creative'' works was released after Creative Commons launched: the +Against DRM License (2006), though it did not achieve wide adoption. +Finally a font-specific copyleft license (SIL Open Font License) was introduced +in 2005 (again the GPL, with a ``font exception'', was and is now +also used for fonts). + +Although CC-BY-SA was used for licensing ``databases'' almost from +its launch, and still is, copyleft licenses specifically intended to be +used for databases were proposed starting from the mid-2000s. The most +prominent of those is the Open Database License (ODbL; 2009). As we +can see public software licenses following the subjection of software +to copyright, interest in public licenses for databases followed the +EU database directive mandating ``sui generis database rights'', +which began to be implemented in member state law starting from +1998. How CC-BY-SA versions address databases is covered below. + +\subsection{Aside on share-alike non-free therefore non-copylefts} + +%FIXME section needs footnotes + +Many licenses intended for use with non-software works include the +``share-alike'' aspect of copyleft: if adaptations are distributed, +to comply with the license they must be offered under the same terms. +But some (excluding those discussed above) do not grant users the +equivalent of all four software freedoms. Such licenses aren't +true copylefts, as they retain a prominent exclusive property +right aspect for purposes other than enforcing all four freedoms +for everyone. What these licenses create are ``semicommons'' or +mixed private property/commons regimes, as opposed to the commons +created by all free licenses, and protected by copyleft licenses. One +reason non-free public licenses might be common outside software, but +rare for software, is that software more obviously requires ongoing +maintenance. Without control concentrated through copyright assignment +or highly asymmetric contributor license agreements, multi-contributor +maintenance quickly creates an ``anticommons'' -- e.g., nobody has +adequate rights to use commercially. + +These non-free share-alike licenses often aggravate freedom and +copyleft advocates as the licenses sound attractive, but typically +are confusing, probably do not help and perhaps stymie the cause of +freedom. There is an argument that non-free licenses offer conservative +artists, publishers, and others the opportunity to take baby steps, +and perhaps support better policy when they realize total control is +not optimal, or to eventually migrate to free licenses. Unfortunately +no rigorous analysis of any of these conjectures. The best that +can be done might be to promote education about and effective use +of free copyleft licenses (as this tutorial aims to do) such that +conjectures about the impact of non-free licenses become about as +interesting as the precise terms of proprietary software EULAs -- +demand freedom instead. + +In any case, some of these non-free share-alike licenses (also +watch out for aforementioned copyleft licenses with non-free and thus +non-copyleft options) include: Open Content License (1998), Free Music +Public License (2001), LinuxTag Yellow, Red, and Rainbow OpenMusic +Licenses (2001), Open Source Music License (2002), Creative Commons +NonCommercial-ShareAlike and Attribution-NonCommercial-ShareAlike +Licenses (2002), Common Good Public License (2003), and Peer Production +License (2013). CC-BY-NC-SA is by far the most widespread of these, +and has been versioned with the other Creative Commons licenses, through the current +version 4.0 (2013). + +\chapter{Creative Commons Attribution-ShareAlike} + +The remainder of this tutorial +exclusively concerns the most widespread copyleft license intended +for non-software works, Creative Commons Attribution-ShareAlike +(CC-BY-SA). But, there are actually many CC-BY-SA licenses -- 5 +versions (6 if you count version 2.1, a bugfix for a few jurisdiction +``porting'' mistakes), ports to 60 jurisdictions -- 96 distinct +CC-BY-SA licenses in total. After describing CC-BY-SA and how it +differs from the GPL at a high level, we'll have an overview of the +various CC-BY-SA licenses, then a section-by-section walkthrough of +the most current and most clear of them -- CC-BY-SA-4.0. + +CC-BY-SA allows anyone to share and adapt licensed material, for +any purpose, subject to providing credit and releasing adaptations +under the same terms. The preceding sentence is a severe abridgement +of the ``human readable'' license summary or ``deed'' provided by +Creative Commons at the canonical URL for one of the CC-BY-SA licenses +-- the actual license or ``legalcode'' is a click away. But this +abridgement, and the longer the summary provided by Creative Commons +are accurate in that they convey CC-BY-SA is a free, copyleft license. + +\section{GPL and CC-BY-SA differences} + +% FIXME this section ought refernece GPL portion of tutorial extensively + +There are several differences between the GPL and CC-BY-SA that are +particularly pertinent to their analysis as copyleft licenses. + +The most obvious such difference is that CC-BY-SA does not require +offering works in source form, that is their preferred form for making +modifications. Thus CC-BY-SA makes a huge tradeoff relative to the +GPL -- CC-BY-SA dispenses with a whole class of compliance questions +which are more ambiguous for some creative works than they are for most +software -- but in so doing it can be seen as a much weaker copyleft. + +Copyleft is sometimes described as a ``hack'' or ``judo move'' +on copyright, but the GPL makes two moves, though it can be hard to +notice they are conceptually different moves, without the contrast +provided by a license like CC-BY-SA, which only substantially makes +one move. The first move is to neutralize copyright restrictions -- +adaptations, like the originally licensed work, will effectively +not be private property (of course they are subject to copyright, +but nobody can exercise that copyright to prevent others' use). If +copyright is a privatized regulatory system (it is), the first move +is deregulatory. The second move is regulatory -- the GPL requires +offer of source form, a requirement that would not hold if copyright +disappeared, absent a different regulatory regime which mandated source +revelation (one can imagine such a regime on either ``pragmatic'' +grounds, e.g., in the interest of consumer protection, or on the +grounds of enforcing software freedom as a universal human right). + +% FIXME analysis of differences in copyleft scope (eg interplay of +% derivative works, modified copies, collections, aggregations, containers) would +% be good here but might be difficult to avoid novel research + +CC-BY-SA makes the first move\footnote{See +\url{https://wiki.creativecommons.org/ShareAlike_interpretation}.} but adds +the second in a limited fashion. It does not require offer of preferred +form for modification nor any variation thereof (e.g., the FDL +requires access to a ``transparent copy''). CC-BY-SA does prohibit +distribution with ``effective technical measures'' (i.e., digital +restrictions management or DRM) if doing so limits the freedoms granted +by the license. We can see that this is regulatory because absent +copyright and any regime specifically limiting DRM, such distribution +would be perfectly legal. Note the GPL does not prohibit distribution +with DRM, although its source requirement makes DRM superfluous, and +somewhat analogously, of course GPLv3 carefully regulates distribution +of GPL'd software with locked-down devices -- to put it simply, it +requires keys rather than prohibiting locks. Occasionally a freedom +advocate will question whether CC-BY-SA's DRM prohibition makes +CC-BY-SA a non-free license. Few if any questioners come down on the +side of CC-BY-SA being non-free, perhaps for two reasons: first, +overwhelming dislike of DRM, thus granting the possibility that +CC-BY-SA's approach could be appropriate for a license largely +used for cultural works; second, the DRM prohibition in CC-BY-SA +(and all CC licenses) seems to be mainly expressive -- there are +no known enforcements, despite the ubiquity of DRM in games, apps, +and media which utilize assets under various CC licenses. + +Another obvious difference between the GPL and CC-BY-SA is that the +former is primarily intended to be used for software, and the latter +for cultural works (and, with version 4.0, databases). Although those +are the overwhelming majority of uses of each license, there are areas +in which both are used, e.g., for hardware design and interactive +cultural works, where there is not a dominant copyleft practice or +the line between software and non-software is not absolutely clear. + +This brings us to the third obvious difference, and provides a reason +to mitigate it: the GPL and CC-BY-SA are not compatible, and have +slightly different compatibility mechanisms. One cannot mix GPL and +CC-BY-SA works in a way that creates a derivative work and comply +with either of them. This could change -- CC-BY-SA-4.0 introduced\footnote{ +\url{https://wiki.creativecommons.org/ShareAlike_compatibility}} +the possibility of Creative Commons declaring CC-BY-SA-4.0 one-way +(as a donor) compatible with another copyleft license -- the GPL is +obvious candidate for such compatibility. Discussion is expected to +begin in late 2014, with a decision sometime in 2015. If this one-way +compatibility were to be enacted, one could create an adaptation of +a CC-BY-SA work and release the adaptation under the GPL, but not +vice-versa -- which makes sense given that the GPL is the stronger +copyleft. + +The GPL has no externally declared compatibility with other licenses +mechanism (and note no action from the FSF would be required for +CC-BY-SA-4.0 to be made one-way compatible with the GPL). The GPL's +compatibility mechanism for later versions of itself differs from +CC-BY-SA's in two ways: the GPL's is optional, and allows for use +of the licensed work and adaptations under later versions; CC-BY-SA's +is non-optional, but only allows for adaptations under later versions. + +Fourth, using slightly different language, the GPL and CC-BY-SA's +coverage of copyright and similar restrictions should be identical for +all intents and purposes (GPL explicitly notes ``semiconductor mask +rights'' and CC-BY-SA-4.0 ``database rights'' but neither excludes +any copyright-like restrictions). But on patents, the licenses are +rather different. CC-BY-SA-4.0 explicitly does not grant any patent +license, while previous versions were silent. GPLv3 has an explicit +patent license, while GPLv2's patent license is implied (see \ref{gpl-implied-patent-grant} +and \ref{GPLv3-drm} for details). This difference ought give serious pause +to anyone considering use of CC-BY-SA for works potentially subject +to patents, especially any potential licensee if CC-BY-SA licensor +holds such patents. Fortunately Creative Commons has always strongly +advised against using any of its licenses for software, and that +advice is usually heeded; but in the space of hardware designs Creative +Commons has been silent, and unfortunately from a copyleft (i.e., use +mechanisms at disposal to enforce user freedom) perspective, CC-BY-SA +is commonly used (all the more reason to enable one-way compatibility, +allowing such projects to migrate to the stronger copyleft). + +The final obvious difference pertinent to copyleft policy between +the GPL and CC-BY-SA is purpose. The GPL's preamble makes it clear +its goal is to guarantee software freedom for all users, and even +without the preamble, it is clear that this is the Free Software +Foundation''s driving goal. CC-BY-SA (and other CC licenses) state +no purpose, and (depending on version) are preceded with a disclaimer +and neutral ``considerations for'' licensors and licensees to +think about (the CC0 public domain dedication is somewhat of an +exception; it does have a statement of purpose, but even that has +more of a feel of expressing yes-I-really-mean-to-do-this than a +social mission). Creative Commons has always included elements +of merely offering copyright holders additional choices and of +purposefully creating a commons. While CC-BY-SA (and initially +CC-SA) were just among the 11 non-mutually exclusive combinations +of ``BY'', ``NC'', ``ND'', and ``SA'', freedom advocates +quickly adopted CC-BY-SA as ``the'' copyleft for non-software works +(surpassing previously existing non-software copylefts mentioned +above). Creative Commons has at times recognized the special role of +CC-BY-SA among its licenses, e.g., in a \href{https://wiki.creativecommons.org/CC_Attribution-ShareAlike_Intent}{statement of intent} +regarding the license made in order to assure Wikimedians considering +changing their default license from the FDL to CC-BY-SA that the +latter, including its steward, was acceptably aligned with the +Wikimedia movement (itself probably more directly aligned with software +freedom than any other major non-software commons). + +% FIXME possibly explain why purpose might be relevant, eg copyleft +% instrument as totemic expression, norm-setting, idea-spreading + +% FIXME possibly mention that CC-BY-SA license text is free (CC0) + +There are numerous other differences between the GPL and CC-BY-SA that +are not particularly interesting for copyleft policy, such as the +exact form of attribution and notice, and how license translations +are handled. Many of these have changed over the course of CC-BY-SA +versioning. + +\section{CC-BY-SA versions} + +%FIXME section ought explain jurisdiction ports + +This section gives a brief overview of changes across the main versions +(1.0, 2.0, 2.5, 3.0, and 4.0) of CC-BY-SA, again focused on changes +pertinent to copyleft policy. Creative Commons maintains a \href{https://wiki.creativecommons.org/License_Versions}{page} +detailing all significant changes across versions of all of its CC-BY* licenses, +in many cases linking to detailed discussion of individual changes. + +As of late 2014, versions 2.0 (the one called ``Generic''; there are +also 18 jurisdiction ports) and 3.0 (called ``Unported''; there are +also 39 ports) are by far the most widely used. 2.0 solely because it +is the only version that the proprietary web image publishing service +Flickr has ever supported. It hosts 27 million CC-BY-SA-2.0 photos +\footnote{As of November 2014. See \url{https://www.flickr.com/creativecommons/} for counts.} and remains the go-to general +source for free images (though it may eventually be supplanted by +Wikimedia Commons, some new proprietary service, or a federation of +free image sharing sites, perhaps powered by GNU MediaGlobin). 3.0 +both because it was the current version far longer (2007-2013) than +any other and because it has been adopted as the default license for +most Wikimedia projects. + +However apart from the brief notes on each version, we will focus on +4.0 for a section-by-section walkthrough in the next section, as 4.0 +is improved in several ways, including understandability, and should +eventually become the most widespread version, both because 4.0 is +intended to remain the current version for the indefinite and long +future, and it would be reasonable to predict that Wikimedia projects +will make CC-BY-SA-4.0 their default license in 2015 or 2016. + +% FIXME subsections might not be the right strcuture or formatting here + +\subsection{1.0 (2002-12-16)} +CC-BY-SA-1.0 set the expectation for future +versions. But the most notable copyleft policy feature (apart from +the high level differences with GPLv2, such as not requiring source) +was no measure for compatibility with future versions (nor with the +CC-SA-1.0, also a copyleft license, nor with pre-existing copyleft +licenses such as GPL, FDL, FAL, and others, nor with CC jurisdiction +ports, of which there were 3 for 1.0). + +\subsection{2.0 (2004-05-25)} +CC-BY-SA-2.0 made itself compatible with +future versions and CC jurisdiction ports of the same version. Creative +Commons did not version CC-SA, leaving CC-BY-SA-2.0 as ``the'' CC +copyleft license. CC-BY-SA-2.0 also adds the only clarification of +what constitutes a derivative work, making ``synchronization of the +Work in timed-relation with a moving image'' subject to copyleft. + +\subsection{2.5 (2005-06-09)} +CC-BY-SA-2.5 makes only one change, to allow +licensor to designate another party to receive attribution. This +does not seem interesting for copyleft policy, but the context of the +change is: it was promoted by the desire to make attribution of mass +collaborations easy (and on the other end of the spectrum, to make it +possible to clearly require giving attribution to a publisher, e.g., +of a journal). There was a brief experiment in branding CC-BY-SA-2.5 +as the ``CC-wiki'' license. This was an early step toward Wikimedia +adopting CC-BY-SA-3.0, four years later. + +\subsection{3.0 (2007-02-23)} +CC-BY-SA-3.0 introduced a mechanism for +externally declaring bilateral compatibility with other licenses. This +mechanism to date has not been used for CC-BY-SA-3.0, in part because +another way was found for Wikimedia projects to change their default +license from FDL to CC-BY-SA: the Free Software Foundation released +FDL 1.3, which gave a time-bound permission for mass collaboration +sites to migrate to CC-BY-SA. While not particularly pertinent to +copyleft policy, it's worth noting for anyone wishing to study +old versions in depth that 3.0 is the first version to substantially +alter the text of most of the license, motivated largely by making +the text use less U.S.-centric legal language. The 3.0 text is also +considerably longer than previous versions. + +\subsection{4.0 (2013-11-25)} +CC-BY-SA-4.0 added to 3.0's +external compatibility declaration mechanism by allowing one-way +compatibility. After release of CC-BY-SA-4.0 bilateral compatibility +was reached with FAL-1.3. As previously mentioned, one-way +compatibility with GPLv3 will soon be discussed. + +4.0 also made a subtle change in that an adaptation may be considered +to be licensed solely under the adapter's license (currently +CC-BY-SA-4.0 or FAL-1.3, in the future potentially GPLv3 or or +a hypothetical CC-BY-SA-5.0). In previous versions licenses were +deemed to ``stack'' -- if a work under CC-BY-SA-2.0 were adapted +and released under CC-BY-SA-3.0, users of the adaptation would +need to comply with both licenses. In practice this is an academic +distinction, as compliance with any compatible license would tend to +mean compliance with the original license. But for a licensee using +a large number of works that wished to be extremely rigorous, this +would be a large burden, for it would mean understanding every license +(including those of jurisdiction ports not in English) in detail. + +The new version is also an even more complete rewrite of 3.0 than 3.0 +was of previous versions, completing the ``internationalization'' +of the license, and actually decreasing in length and increasing +in readability. + +Additionally, 4.0 consistently treats database (licensing them +like other copyright-like rights) and moral rights (waiving them to +the extent necessary to exercise granted freedoms) -- in previous +versions some jurisdiction ports treated these differently -- and +tentatively eliminates the need for jurisdiction ports. Official +linguistic translations are underway (Finnish is the first completed) +and no legal ports are planned for. + +4.0 is the first version to explicitly exclude a patent (and less +problematically, trademark) license. It also adds two features akin to +those found in GPLv3: waiver of any right licensor may have to enforce +anti-circumvention if DRM is applied to the work, and reinstatement +of rights after termination if non-compliance corrected within 30 days. + +Finally, 4.0 streamlines the attribution requirement, possibly of some +advantage to massive long-term collaborations which historically have +found copyleft licenses a good fit. + +The 4.0 versioning process was much more extensively researched, +public, and documented than previous CC-BY-SA versionings; +see \url{https://wiki.creativecommons.org/4.0} for the record and +\url{https://wiki.creativecommons.org/Version_4} for a summary of +final decisions. + + +\section{CC-BY-SA-4.0 International section-by-section} + +% FIXME arguably this section ought be the substance of the tutorial, but is very thin and weak now + +% FIXME formatted/section-referenced copy of license should be added to license-texts.tex +% and referenced througout + +The best course of action at this juncture would be to read +\url{http://creativecommons.org/licenses/by-sa/4.0/legalcode} -- the entire +text is fairly easy to read, and should be quickly understood if one +has the benefit of study of other public licenses and of copyleft +policy. + +The following walk-through will simply call out portions of each +section one may wish to study especially closely due to their +pertinence to copyleft policy issues mentioned above. + +% FIXME subsections might not be the right strcuture or formatting here + +\subsection{1 -- Definitions} + +The first three definitions -- ``Adapted Material'', ``Adapter's +License'', and ``BY-SA Compatible License'' are crucial to +understanding copyleft scope and compatibility. + +\subsection{2 -- Scope} + +The license grant is what makes all four freedoms available to +licensees. This section is also where waiver of DRM anti-circumvention +is to be found, also patent and trademark exclusions. + +\subsection{3 -- License Conditions} + +This section contains the details +of the attribution and share-alike requirements; the latter read +closely with aforementioned definitions describe the copyleft aspect +of CC-BY-SA-4.0. + +\subsection{4 -- Sui Generis Database Rights} + +This section describes how the previous grant and condition sections +apply in the case of a database subject to sui generis database +rights. This is an opportunity to go down a rabbit-hole of trying to +understand sui generis database rights. Generally, this is a pointless +exercise. You can comply with the license in the same way you would if +the work were subject only to copyright -- and determining whether a +database is subject to copyright and/or sui generis database rights is +another pit of futility. You can license databases under CC-BY-SA-4.0 +and use databases subject to the same license as if they were any other +sort of work. + +\subsection{5 -- Disclaimer of Warranties and Limitation of Liability} + +Unsurprisingly, this section does its best to serve as an ``absolute +disclaimer and waiver of all liability.'' + +\subsection{6 -- Term and Termination} + +This section is similar to GPLv3, but without special provision for +cases in which the licensor wishes to terminate even cured violations. + +\subsection{7 -- Other Terms and Conditions} + +Though it uses different language, like the GPL, CC-BY-SA-4.0 does +not allow additional restrictions not contained in the license. Unlike +the GPL, CC-BY-SA-4.0 does not have an explicit additional permissions +framework, although effectively a licensor can offer any other terms +if they are the sole copyright holder (the license is non-exclusive), +including the sorts of permissions that would be structured as +additional permissions with the GPL. Creative Commons has sometimes +called offering of separate terms (whether additional permissions or +``proprietary relicensing'') the confusing name ``CC+''; however +where this is encountered at all it is usually in conjunction with one +of the non-free CC licenses. Perhaps CC-BY-SA is not a strong enough +copyleft to sometimes require additional permissions, or be used to +gain commercially valuable asymmetric rights, in contrast with the GPL. + +\subsection{8 -- Interpretation} + +Nothing surprising here. Note that CC-BY-SA does not ``reduce, limit, +restrict, or impose conditions on any use of the Licensed Material that +could lawfully be made without permission under this Public License.'' +This is a point that Creative Commons has always been eager to make +about all of its licenses. GPLv3 also ``acknowledges your rights +of fair use or other equivalent''. This may be a wise strategy, +but should not be viewed as mandatory for any copyleft license -- +indeed, the ODbL attempts (somewhat self-contradictorily; it also +acknowledges fair use or other rights to use) make its conditions +apply even for works potentially subject to neither copyright nor +sui generis database rights. + + +\section{Enforcement} + +There are only a small number of court cases involving any Creative +Commons license. Creative Commons lists these and some related cases +at \url{https://wiki.creativecommons.org/Case_Law}. + +Only two of those cases concern enforcing the terms of a CC-BY-SA +license (Gerlach v. DVU in Germany, and No. 71036 N. v. Newspaper +in a private Rabbinical tribunal) each hinged on attribution, +not share-alike. + +Further research could uncover out of compliance uses being +brought into compliance without lawsuit, however no such +research, nor any hub for conducting such compliance work, +is known. Editors of Wikimedia Commons document some external +uses of Commons-hosted media, including whether user are compliant +with the relevant license for the media (often CC-BY-SA), resulting in a +\href{https://commons.wikimedia.org/wiki/Category:Files_reused_by_external_parties_out_of_compliance_with_licensing_terms}{category} listing non-compliant uses (which seem to almost exclusively concern attribution). + +\section{Compliance Resources} + +% FIXME this section is just a stub; ideally there would also be an addition section +% or chapter on CC-BY-SA compliance + +Creative Commons has a page on +\href{https://wiki.creativecommons.org/ShareAlike_interpretation}{ShareAlike +interpretation} as well as an extensive Frequently Asked Questions +\href{https://wiki.creativecommons.org/Frequently_Asked_Questions#For_Licensees}{for +licensees} which addresses compliance with the attribution condition. + +\href{https://en.wikipedia.org/wiki/Wikipedia:Reusing_Wikipedia_content}{English +Wikipedia}'s and +\href{https://commons.wikimedia.org/wiki/Commons:Reusing_content_outside_Wikimedia}{Wikimedia +Commons}' pages on using material outside of Wikimedia projects provide +valuable information, as the majority of material on those sites is +CC-BY-SA licensed, and their practices are high-profile. + +% FIXME there is no section on business use of CC-BY-SA; there probably ought to be +% as there is one for GPL, though there'd be much less to put. + +% ===================================================================== +% END OF ATTRIBUTION-SHAREALIKE SECTION +% ===================================================================== + +%% LocalWords: ShareAlike