Creative Commons is a not-for-profit organization that has created and serves as a steward for a suite of copyright licenses that enable creators to legally grant certain freedoms to the public and to clearly signal those freedoms to humans and machines.
Creative Commons Attribution-ShareAlike licenses play a particularly important role in the Free or Libre Culture movement. This document lays out Creative Commons' intention as steward for this class of licenses.
First, it is important to understand the activities Creative Commons undertakes as a steward of licenses:
Millions of creators and users expect Creative Commons to undertake these stewardship activities, and we recognize and attempt to follow through with this great responsibility. The responsibility to communities using Attribution-ShareAlike licenses is even greater, as many in those communities rely on Creative Commons to serve as a reliable steward not just in a practical legal and technical sense, but in an ideological sense.
Creative Commons Attribution-ShareAlike licenses are informed and inspired by the principles and lessons of the Free Software movement. Although certain Creative Commons licenses allow granting of relatively narrow freedoms, in this document we use Free and Libre in the sense used by the Free Software movement. As applied to content, these principles require a license to grant the following essential freedoms to ALL users of licensed works:
These freedoms are taken directly from the Definition of Free Cultural Works, and more thoroughly explained there. Thus, the first commitment of Creative Commons as steward of Attribution-ShareAlike licenses:
1) All versions and ports of Creative Commons Attribution-ShareAlike licenses MUST satisfy the definition of a Free Cultural License set out in the Definition of Free Cultural Works.
However, a license without the ShareAlike requirement could satisfy this definition. The crucial lesson learned from the Free Software movement is that Freedom is a public good, and the dominant Free license should not only grant essential freedoms, but protect those freedoms for all users. This is accomplished by copyleft, which adds a requirement that anyone distributing a copy of a Free work or an adaptation (also known as a derivative) of that work grant to other users the same freedoms they received. The GNU General Public License is the dominant copyleft software license, indeed the dominant Free Software license (Creative Commons uses and recommends the GNU GPL for software).
For its content licenses, Creative Commons calls the copyleft requirement ShareAlike. This requirement protects the freedoms of all users by requiring that adaptations of works licensed under Attribution-ShareAlike to also be distributed under an Attribution-ShareAlike license, or a license deemed by Creative Commons to grant and protect the same essential freedoms for all users in a compatible fashion. Thus, the second commitment of Creative Commons as steward of Attribution-ShareAlike licenses:
2) All versions and ports of Creative Commons Attribution-ShareAlike licenses MUST protect the freedom of all users by requiring that when an adaptation of a work distributed under an Attribution-ShareAlike license is distributed, the adaptation must be distributed under the same license, or a license deemed by Creative Commons to grant and protect the same essential freedoms for all users in a compatible fashion (to be clear, such a compatible license must also satisfy the definition of a Free Cultural License set out in the Definition of Free Cultural Works).
As described above, the ShareAlike requirement becomes active when an adaptation of a licensed work is distributed. Creative Commons may choose to add language to future versions of its licenses specifying that particular uses constitute adaptations from the perspective of the license, where such may not be clear. For example, since version 2.0, Creative Commons Attribution-ShareAlike licenses have included language similar to the following:
It would abuse the trust of licensors to add a clarification that narrowed the scope of what is considered an adaptation, for this would introduce a loophole by which the freedom of all users would not be protected. As such, the third commitment of Creative Commons as steward of Attribution-ShareAlike licenses:
3) Any clarification of whether a use constitutes an adaptation for the purposes of Attribution-ShareAlike licenses may only broaden the scope of uses considered adaptations rather than collections.
When a copyleft license is widely used, it not only protects essential freedoms for all users, it fosters the spread of those freedoms. This occurs when people who may not know or care about Freedom as understood by the Free Software movement, but merely wish to use works that happen to be Free, release adaptations under a Free license in order to fulfill the requirements of the license. By the same token, if there are pools of Free content that may not be mixed because their copyleft style licenses are legally incompatible, the spread of essential freedoms is constricted. The fourth commitment of Creative Commons as steward of Attribution-ShareAlike licenses could be seen as implicit in the second commitment, but it is important to call out separately here:
4) Creative Commons will strive to enable compatibility between Attribution-ShareAlike licenses and other copyleft content licenses that grant and protect the same essential freedoms for all users (to be clear, any candidate for compatibility must also satisfy the definition of a Free Cultural License set out in the Definition of Free Cultural Works).
While every work that expands the universe of Free or Libre content is important, Free licenses play an especially crucial role for works with many collaborators. Unless each collaborator agrees to contribute under the terms of a Free license, the work rapidly becomes unusable by anyone, as past contributors must either be tracked down, or their contributions excised, before the work may be distributed or built upon (except as permitted by fair use and other limitations on copyright). But Free licenses are not enough for massively collaborative projects. In addition to social and technical affordances thankfully beyond the scope of copyright, such projects need particular licensing affordances, particularly around attribution requirements. Creative Commons took a step toward addressing these needs in version 2.5 of its licenses, but there may be more to do in this regard. Thus, the fifth commitment of Creative Commons as steward of Attribution-ShareAlike licenses.
5) Creative Commons will strive to ensure that Attribution-ShareAlike licenses meet the needs of massively collaborative works, while remaining useful for works with one or a few creators.
Our final commitment is a simple restatement of one of the stewardship activities described above, with emphasis on Free and Libre content communities and Attribution-ShareAlike:
6) Maintain close contact with Free and Libre content communities to ensure Attribution-ShareAlike licenses and associated tools are serving these communities well.
If you are a member of one of these communities, take this as an invitation to help us meet these commitments to you. Friendly suggestions for improvement and criticism if we seem to go astray are equally valuable.