The FSF Clarifies: You Can't Use the GNU (A)GPL to Restrict Software Freedom

The Free Software Foundation has issued a strong statement clarifying that the GNU family of General Public Licenses, including the Affero General Public License version 3 (AGPLv3), cannot be used to restrict software freedom. This comes in response to OnlyOffice's use of a modified version of the AGPLv3 that includes additional terms inconsistent with the license's intended purpose.

The FSF, as the steward of the GNU licenses, emphasizes that these licenses were carefully drafted to ensure copyright holders have a tool to release programs as free software while protecting and preserving the freedoms of computer users. The core principles of free software include the freedom to run, copy, study, change, improve, and distribute software.

According to Krzysztof Siewicz of the FSF, the foundation has always allowed everyone to use their licenses as intended, in line with these core principles. The FSF favors compliance and constructive dialogue in resolving licensing issues and is always happy to see more programs properly released under one of their licenses.

However, the situation with OnlyOffice has raised concerns. The FSF was recently mentioned by Lev Bannov of the OnlyOffice project in connection with their use of a modified version of the AGPLv3. This, combined with OnlyOffice's public position regarding its recent Euro-Office fork, suggests an attempt to impose additional restrictions on the AGPLv3 that are inconsistent with the freedoms granted by the license.

The FSF would have been happy to offer guidance in private before OnlyOffice published the license with additional restrictions, as they do for many other projects. They would still be willing to assist OnlyOffice in aligning its approach with the intended use of the AGPLv3. However, since any effort to put (A)GPL-incompatible terms on an (A)GPL license confuses users about their freedoms, the FSF feels it is their duty to clarify how the AGPLv3 is intended to work.

It is possible to modify the (A)GPLv3 with additional terms, but only by adhering to the terms of the license itself. One can also legally use the (A)GPL terms (possibly modified) in another license imposing terms outside of what the (A)GPLv3 allows, but then referring to the license as "the (A)GPL" would be false.

The FSF's Frequently Asked Questions on GNU Licenses describe the requirements for this kind of license modification to ensure the resulting license is never confused with any of the FSF's licenses. In the main repository of the OnlyOffice DocumentServer, the README file clearly states that the software is made available under the AGPLv3 in the "License" section. However, OnlyOffice then includes additional terms in the LICENSE file and in some other LICENSE files in other repositories, as well as in license notices of individual source files.

For example, in utils.js, there is a notice stating: "Pursuant to Section 7(b) of the License you must retain the original Product logo when distributing the program." This obligation to "retain the original Product logo" is not included in Sec. 7(b) of the (A)GPLv3, nor in any other parts, as an (A)GPL-compliant additional term, and is therefore considered a further restriction of the (A)GPLv3.

The (A)GPLv3 makes it clear that it permits all licensees to remove any additional terms that are "further restrictions" under the (A)GPLv3. It states, "[i]f the Program as you received it, or any part of it, contains a notice stating that it is governed by this License along with a term that is a further restriction, you may remove that term."

The FSF encourages everyone to carefully read their licenses and consult their published materials before attempting to develop additional terms. They host the documentation of the (A)GPLv3 drafting process and have published recommendations for (A)GPL-compliant additional terms that require preserving author attributions or legal notices. People can also write to them at [email protected] with licensing questions.

Modifying a GNU license with additional terms in a manner consistent with the intended purpose of the license is good for software freedom. However, it is the FSF's duty to react when GNU licenses are misused by altering them with terms that confuse users about the freedoms they grant. The FSF cannot allow anyone to make unauthorized derivative works of their licenses, nor allow or accept confusing uses of the FSF's trademarks.

The FSF urges OnlyOffice to clarify the situation by making it unambiguous that OnlyOffice is licensed under the AGPLv3, and that users who already received copies of the software are allowed to remove any further restrictions. Additionally, if OnlyOffice intends to continue to use the AGPLv3 for future releases, they should state clearly that the program is licensed under the AGPLv3 and make sure they remove any further restrictions from their program documentation and source code.

Confusing users by attaching further restrictions to any of the FSF's family of GNU General Public Licenses is not in line with free software principles. The FSF's stance reinforces the importance of maintaining the integrity of free software licenses and ensuring that users' freedoms are not compromised by additional restrictions that go beyond the scope of the original licenses.