debian-legal Summary of Creative Commons 2.0 Licenses

Author:	Evan Prodromou <evan@debian.org>
Date:	3 April 2005
Version:	4
Contact:	debian-legal mailing list <debian-legal@lists.debian.org>
Copyright:	This document is dedicated by the author to the public domain.

This document gives a summary of the opinion of debian-legal members on the six licenses that make up the Creative Commons license suite.

About debian-legal

Debian [DEBIAN] is an operating system consisting entirely of Free Software. Our criteria for "Free Software" are specified in the Debian Free Software Guidelines [DFSG].

debian-legal [LEGAL] is a mailing list whose members provide guidance for the Debian project on, among other things, the acceptability of software and other content for inclusion in the Debian operating system. This includes comparing software against the DFSG to determine if the packages are Free Software.

From time to time the debian-legal list provides a review of a well-known software license to express a rough consensus opinion on whether software released solely under the license would be Free Software. Although these summaries are not binding, they do provide some basis for the Debian project to make decisions about individual packages.

About Creative Commons

Creative Commons [CC] is an organization "devoted to expanding the range of creative work available for others to build upon and share." The organization has created a suite of licenses [LICENSES] that content creators can use to specify certain rights that the public can exercise with respect to a particular work. The licenses were released in December of 2002 and revised in May of 2004. There are many works available under Creative Commons licenses -- estimates range from the tens of thousands to the tens of millions.

Although Creative Commons explicitly recommends that their licenses not be used for programs [1], works licensed under the Creative Commons licenses are still of interest to the Debian project. Debian includes documentation for programs, and many programs included in Debian use digital data such as images, sounds, video, or text that are included with the programs in Debian.

The Creative Commons licenses are based on a common framework, but have a varied number of license elements that can be included to grant or revoke particular rights. Because of the similarity between the licenses, this document covers all six of the revised (version 2.0) licenses.

License summaries

Attribution 2.0

debian-legal contributors think that works licensed solely under the Creative Commons Attribution 2.0 license [BY] are not free according to the DFSG and should not be included in Debian.

We see the following problems with the license.

Removing References

Section 4a of the license states, in part,

If You create a Collective Work, upon notice from any Licensor You must, to the extent practicable, remove from the Collective Work any reference to such Licensor or the Original Author, as requested. If You create a Derivative Work, upon notice from any Licensor You must, to the extent practicable, remove from the Derivative Work any reference to such Licensor or the Original Author, as requested.

Per DFSG 3, any licensee should be allowed to make and distribute modified versions of a work. The above clause allows a licensor to prohibit modified versions that mention them or reference them.

For example, an author who made a novel available under an Attribution 2.0 license could give notice to disallow an annotated version that mentions the author by name or simply as "the author".

A more specific example for Debian would be a programmer who creates documentation licensed under Attribution 2.0. He could require that references in derived versions to design or implementation decisions he made for the program be removed.

In addition, Section 4b of the license requires that the author's name, copyright notices, and some other information be included in derivative works, "if supplied".

It's unclear whether the creator of a derivative work can comply with the requirement to remove references and also comply with the requirement to give attribution. It's not specified that a licensee who has been asked to remove references to the licensor has the requirements of attribution waived.

If a request to remove references can make it impossible for licensees to comply with section 4b, and thus makes it impossible for them make derivative works (DFSG 3) or collective works (DFSG 1), the work is not free.

Any Other Comparable Authorship Credit

Section 4b describes the requirements for crediting the Licensor for his or her work. It states, in part:

Such credit may be implemented in any reasonable manner; provided, however, that in the case of a Derivative Work or Collective Work, at a minimum such credit will appear where any other comparable authorship credit appears and in a manner at least as prominent as such other comparable authorship credit.

There are several ambiguous or vague terms in this clause.

"any other": This can mean "some other" or "all other". The first would mean that authorship must be credited somewhere, and particularly where other credit goes. The second would mean that authorship must be credited everywhere that authors are credited.
"comparable authorship credit": This could mean either "credit for comparable authorship" or "comparable credit for authorship". The first interpretation would allow crediting an author with all other authors who have made similar contributions. The second would require crediting the author where any author is credited, even if the level of contribution is not comparable.

A licensee cannot exercise the rights granted in the license if they can't meet these requirements. For this reason, the most pessimistic interpretation of the requirements must be used. This would require attribution for the licensor everywhere that authorship credit is given, even if that credit is inaccurate, and even if the licensor's contribution is not comparable to others. Some examples:

If a work is a collection of essays by different authors, with authorship credit given in the chapter titles, the Licensor's name would have to be listed for each chapter title, even if they did not contribute to it.
For an encyclopedia with a large number of authors, all authors would be listed at every point of authorship notice: on the spine, on the front and back covers, on the title page.
If Alice writes her autobiography, and includes lyrics from Bob's song in one chapter, she must give him credit for the entire work: "The Autobiography of Alice, by Alice and Bob", or even The Autobiography of Alice and Bob.

Requiring inaccurate or excessive authorship credits is an unreasonable restriction on distribution (DFSG 1) and making modified versions (DFSG 3).

Anti-DRM clause

Section 4a says, in part,

You may not distribute, publicly display, publicly perform, or publicly digitally perform the Work with any technological measures that control access or use of the Work in a manner inconsistent with the terms of this License Agreement.

There is not a clearly defined metric for determining if a measure is consistent with the terms of the license.

In the absence of any other information, technologies enabling private distribution of the work would seem to be forbidden. Along with obvious technological measures that control access, such as a firewall on a LAN or a virtual private network (VPN), distributing using encryption (such as Secure Sockets Layer (SSL)) would appear to be prohibited.

DFSG 1 requires that works be freely redistributable, both publicly and privately. Disallowing private distribution appears to be incompatible with that goal.

Trademark Restrictions

The only version of the license available from Creative Commons is a Web page that includes the following text:

Except for the limited purpose of indicating to the public that the Work is licensed under the CCPL, neither party will use the trademark "Creative Commons" or any related trademark or logo of Creative Commons without the prior written consent of Creative Commons.

These restrictions make excessive demands on both licensor and licensee, and abridge their fair use rights to the Creative Commons trademarks. This puts an excessive burden on the licensee and effectively prevents redistribution (DFSG 1) and modification (DFSG 3). In addition, it violates DFSG 9, "License Must Not Contaminate Other Software", since it prohibits fair use of the trademark even in works unrelated to the current one.

Creative Commons representatives have stated that the trademark restrictions are not part of the license [2]. The HTML source code for the Web page includes a comment, normally invisible to the reader, that the trademark restrictions are "NOT A PART OF THE LICENSE". In a graphical Web browser, the text for the trademark restrictions are visually distinct from the license text. Finally, the same block of text states, "Creative Commons is not a party to this License, [...]".

However, debian-legal feels that the visual distinctions are not clear enough to indicate that the trademark restrictions are not part of the license. Some instances of the license found in the wild include the trademark restrictions. It is difficult for a licensor or licensee to know that they can safely ignore the excessively restrictive text.

Attribution-ShareAlike 2.0

debian-legal contributors think that works licensed solely under the Attribution-ShareAlike 2.0 [BY-SA] are not free according to the DFSG and should not be included in Debian.

The Attribution-ShareAlike has the same problems as the Attribution 2.0 license.

NoDerivs licenses

debian-legal contributors think that works licensed solely under licenses with the NoDerivs license element are not free according to the DFSG and should not be included in Debian. These licenses include:

the Attribution-NoDerivs 2.0 license [BY-ND]
the Attribution-NonCommercial-NoDerivs 2.0 license [BY-NC-ND]

These licenses have the same problems as the Attribution 2.0 license. In addition, there is no grant of rights to make derivative works, which is required by DFSG 3.

NonCommercial licenses

debian-legal contributors think that works licensed solely under licenses with the NonCommercial license element are not free according to the DFSG and should not be included in Debian. These licenses include:

Attribution-NonCommercial-NoDerivs 2.0 license
Attribution-NonCommercial 2.0 license [BY-NC]
Attribution-NonCommercial-ShareAlike 2.0 license [BY-NC-SA]

These licenses have the same problems as the Attribution 2.0 license. In addition, Section 4b (Section 4c in the by-nc-sa 2.0) says:

You may not exercise any of the rights granted to You in Section 3 above in any manner that is primarily intended for or directed toward commercial advantage or private monetary compensation.

This is incompatible with DFSG 6, "No Discrimination Against Fields of Endeavor", which includes discrimination against businesses. It's also incompatible with DFSG 1, which requires that licensees be allowed to sell copies of the work.

Recommendations for Authors

debian-legal contributors recommend that authors who wish to create works compatible with the Debian Free Software Guidelines should not use any of the licenses in the Creative Commons license suite.

Authors who use or are planning to use a Creative Commons license that includes the NonCommercial or NoDerivs license elements should understand that these restrictions are incompatible with Free Software.

Authors who use or are planning to use the Attribution 2.0 license should consider a similar Free Software license such as a BSD- or MIT-style license [BSD], [MIT].

Authors who use or are planning to use the Attribution-ShareAlike 2.0 license should consider a similar Free Software license such as the GNU General Public License [GPL].

Recommendations for Creative Commons

debian-legal contributors believe that problems with the Creative Commons licenses that include the NoDerivs or NonCommercial license elements cannot be fixed without changing the apparent purpose of the licenses.

The Attribution and Attribution-ShareAlike licenses, however, seem to be intended to make works Free in a way compatible with the DFSG. For this reason, we make the following suggestions for future versions of the Attribution and Attribution-ShareAlike licenses that, barring other changes, should make the licenses compatible with the DFSG.

Limit scope of requests to remove references. The intention of the clause for removing references to a licensor seems to be that authorship credits should be removed. This should be specified, rather than "any reference". Some suggested text for section 4a:

If You create a Collective Work, upon notice from any Licensor You must, to the extent practicable, remove from the Collective Work any authorship credit for such Licensor or the Original Author, as requested. If You create a Derivative Work, upon notice from any Licensor You must, to the extent practicable, remove from the Derivative Work any authorship credit for such Licensor or the Original Author, as requested.
Waive attribution after request to remove references. It should be made explicit that if the Licensor requires that references to them be removed, this excuses the licensee from the requirements for attribution. A modification to section 4b might be:

[...] by conveying the name (or pseudonym if applicable) of the Original Author if supplied and no request has been made to remove it; [...]
Allow access-controlled private distribution. The anti-DRM clause should be changed to make it clear that the licensee can't prevent others receiving the work from exercising the same rights that the licensee has.
Allow distribution of rights-restricted copies of works if unrestricted copies are also made available. The following modified version of the anti-DRM clause in section 4a may be a good starting point.

You may not distribute, publicly display, publicly perform, or publicly digitally perform the Work with any technological measures that prevent the recipient from exercising the rights granted to them by section 8a and section 3 of this License, unless you also distribute, publicly display, publicly perform or publicly digitally perform the Work for the same recipient without those measures.
Require "credit for comparable authorship" rather than "comparable authorship credit". This makes it clear that the Licensor should be credited in proportion to their contribution, rather than equally to all other authors.
Specify "other credit". Licensors should receive some credit, but adding their name wherever any credit is made is excessive and inaccurate. Suggested text:

[...] at a minimum such credit will appear where other credit for comparable authorship appears and in a manner at least as prominent as such other credit for comparable authorship.
More clearly identify non-license trademark restrictions. The trademark restrictions should be clearly labelled, in text and not in the comments, as not part of the license. Separating the organization's trademark policy into another, linked document would be clearer still.
Rephrase overreaching trademark restrictions. The trademark restrictions should be relaxed or rephrased so that licensors and licensees are not denied rights to the Creative Commons trademarks they would have if they did not use the licenses. Suggested text:

Creative Commons grants everyone a license to use the trademark "Creative Commons" and related trademarks and logos to indicate to the public that the Work is licensed under the CCPL. Creative Commons reserves all other rights to its trademarks under trademark law; nobody may use the trademark "Creative Commons" or any related trademark or logo of Creative Commons without the prior written consent of Creative Commons, except as allowed under trademark law.

Note that new versions will be evaluated on their own, and problems introduced in the new version or that weren't covered in this summary may still make the licenses incompatible with the DFSG. In other words, these suggestions come with no guarantees.