Software Freedom Conservancy

Free Software Foundation Issues Statement in Support of Community's ZFS Concerns

by Bradley M. Kuhn and Karen M. Sandler on April 11, 2016

FSF Confirms Conservancy's Analysis & Urges ZFS Copyright Holders to License Under GPL

In a statement today, the Free Software Foundation (FSF), the charity that publishes all versions of the GNU General Public License (GPL), issued a statement regarding GPL-incompatible licenses and their interactions with strong copyleft licenses. The statement, written by Richard M. Stallman, President of the FSF and author of all versions of the GPL, confirms various points that we made previously in our blog post on the matter in late February.

The FSF's statement covers various topics, but most importantly, it confirms that distribution of software created by combining GPL-incompatibly licensed copyrighted works with GPL'd works violates GPL, stating:

The only permissible way to make available a binary (non-source) work that includes GPL'd material is under the GPL. … Code under GPL-incompatible licenses cannot be added, neither in source nor binary form, without violating the GPL.

The FSF's statement also reiterates many important points that are central to Conservancy's work on GPL compliance, particularly as it relates to combined works, such as Linux modules, which are “dynamically linked”:

[I]f you distribute modules meant to be linked together by the user, you have made them into a combined work, and you must release the entire combined work under the GNU GPL.

Specifically regarding the ZFS matter, the FSF has joined Conservancy in calling on Oracle to also license their ZFS copyrights under GPL, so that combinations with Linux are permitted:

[T]he copyright holders of ZFS … can give permission to use it under the GNU GPL, version 2 or later, in addition to any other license. This would make it possible to combine that version with Linux without violating the license of Linux. This would be the ideal resolution and we urge the copyright holders of ZFS to do so.

The FSF does point out that as stewards of the GNU project, they look to organizations like Conservancy, with a direct relationship with substantial Linux copyright holders, to assure compliance with the GPL for Linux. The FSF lauded our efforts to enforce the GPL, concluding with:

[W]e enthusiastically encourage enforcement of the GPL on Linux in accord with the Principles of Community-Oriented GPL Enforcement, and we wish the enforcers success in bringing violators into compliance, thus maintaining the GPL's integrity so it can defend users' freedom.

Both of us, in addition to our work in our day jobs with Conservancy, also volunteer our time to help the FSF — Bradley has been an FSF volunteer (focused primarily on licensing issues) since 1997 and Karen since 2006. We have been grateful to have a fruitful collaborative relationship with the FSF, and we appreciate that both John Sullivan and Richard Stallman actively sought our direct feedback and input on the FSF's statement over the last month.

Conservancy has also engaged in many more formal collaborations with the FSF in the past two years. Most notably, Conservancy and FSF co-published the aforementioned Principles of Community-Oriented GPL Enforcement. Conservancy and the FSF also jointly manage the effort, which publishes the most comprehensive guide ever created on the use of and compliance with GPL and copyleft.

In the six weeks since publication of our blog post about the license compliance problems with Canonical, Ltd.'s inclusion of ZFS in Ubuntu, some have opined with statements that do not fit with the interpretations and analysis that the FSF has carefully created over the last 30 years regarding how copyleft works. We believe the FSF's statement definitively settles this issue, showing that the FSF position remains consistent. We're glad the FSF has clarified the confusion created by the many pundits who have published inaccurate licensing advice.

Conservancy, now joined by the FSF, continue to call on copyright holders of ZFS to end the licensing problems and simply grant permission under GPL for ZFS' inclusion in Linux. Without such permission, users who seek to combine Linux and ZFS live in a precarious situation without the necessary copyright permissions to exercise their software freedom. The easiest path to resolution is a responsible and community-friendly licensing action by ZFS's copyright holders. Oracle should lead the way, as the largest single copyright holder in the ZFS codebase, to either relicense ZFS, or, if they prefer, publish an updated CDDL that is compatible with the GPLv2 and GPLv3 (which would be another viable route to solve the same problem).

Tags: conservancy, GPL

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