FSF clarifies its stance on AGPLv3 additional terms [LWN.net]

OnlyOffice CEO Lev Bannov has recently claimed that the Euro-Office fork of the OnlyOffice suite violates the GNU Affero General Public License version 3 (AGPLv3). Krzysztof Siewicz of the Free Software Foundation (FSF) has published an article on the FSF's position on adding terms to the AGPLv3. In short, Siewicz concludes that OnlyOffice has added restrictions to the license that are not compatible with the AGPLv3, and those restrictions can be removed by recipients of the code.

We urge 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 they intend 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.

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ironic (ugly, good)

Posted Apr 16, 2026 0:07 UTC (Thu) by vuji (guest, #182841) [Link] (5 responses)

* arbitary insertion of conditons gone unnoticed for more than a decade ?
* fsf prompt detailed reply should silence everybody

Yet, an overall good outcome so far

Posted Apr 16, 2026 7:34 UTC (Thu) by fredrik (subscriber, #232) [Link] (3 responses)

Not sure the two contradicting conditions has gone unnoticed, it could simply be that no one has cared enough until now. And when Onlyoffice stirred the got caught by the Streisand effect.

Still, FSF's clarification and comment on this particular case is welcome. If you read the license text of the AGPL very selectively, I can see how one erroneously can argue that Onlyoffice is in the right.

> 7. Additional Terms.
> [...]
> b) Requiring preservation of specified reasonable legal notices or author attributions in that material or in the Appropriate Legal Notices displayed by works containing it; or
> [...]
> d) Limiting the use for publicity purposes of names of licensors or authors of the material; or [...]

Let me emphasize that I'm not arguing that Onlyoffice are right, nor do I believe they are.

My point is that it is good that FSF has chosen to comment publicly on this particular case, as it thoroughly eliminates any FUD arguments that Onlyoffice have been able to ride on so far.

Let's see how Onlyoffice responds to this. I'd be surprised if they followed the FSF advice. Do they collect contributor copyright assignment from third party contributors?

Yet, an overall good outcome so far

Posted Apr 16, 2026 8:13 UTC (Thu) by kxxt (subscriber, #172895) [Link] (1 responses)

> Do they collect contributor copyright assignment from third party contributors?

Yes, A CLA is at https://cla-assistant.io/ONLYOFFICE/build_tools.

But there are some PRs that slipped through without CLA signing, like https://github.com/ONLYOFFICE/build_tools/pull/878 . I am not exactly sure why.

Yet, an overall good outcome so far

Posted Apr 16, 2026 11:53 UTC (Thu) by misc (subscriber, #73730) [Link]

I think that's likely a application of the de minimis doctrine, eg that's a change too trivial to require a CLA or be copyrighted. That's just a cleanup of comma, and it doesn't demonstrate originality or anything that would be copyrightable, ergo, there is likely nothing to transfers.

Yet, an overall good outcome so far

Posted Apr 16, 2026 12:10 UTC (Thu) by misc (subscriber, #73730) [Link]

But 7.b is about CMI (Copyright Management Information, see US Code title 17, chapter 12), so it likely wouldn't apply to the logo preservation clause for 2 reasons.

First, it seems that at least one US Court have decided in 2021 that a logo is not a CMI ( CoStar Group, Inc. et al v. Commercial Real Estate Exchange, Inc, in California ). I have not found much on that topic, but I do not think it was overturned (at least on that point), nor sure if it has a wide impact (besides that circuit).

But second, since the company has a different name (Ascensio System SIA), it is hard to argue that keeping the OnlyOffice logo and branding would be related to copyright management (since this say nothing precise about copyright).

ironic (ugly, good)

Posted Apr 16, 2026 10:06 UTC (Thu) by ballombe (subscriber, #9523) [Link]

Lev Bannov explicitly asked the FSF to review this:
<https://www.onlyoffice.com/blog/2026/03/interview-with-le...>
> If the Euro-Office team believes our approach conflicts with the AGPLv3 license, we invite them to submit an official request to FSF (Free Software Foundation) for review. Let the respected open-source community evaluate the situation and provide a decision. If FSF determines that our license and project align with AGPLv3, we will continue as an open-source initiative. However, if the decision goes against us, we are ready to consider other options.

So it makes sense they are giving their opinion now.
They are not the copyright holders after all.

OnlyOffice is NOT fully open-source

Posted Apr 16, 2026 0:28 UTC (Thu) by kxxt (subscriber, #172895) [Link] (1 responses)

I wonder if FSF know that OnlyOffice is not even fully open source. For a package maintainer, it is easy to find that the CEF binary they use is not open-source: https://github.com/ONLYOFFICE/DesktopEditors/issues/1664#... . Swapping that proprietary CEF binary with the binary from upstream CEF releases in onlyoffice would result in a crash. So clearly onlyoffice modified CEF and didn’t open-source it.

Ironically they are downloading that binary at build time using an unencrypted http link without doing even integrity check, leaving users to supply chain risks as a man-in-the-middle attacker could just inject some malware into their CEF binary when they are downloading it. I hope that they only slightly modified CEF for good purposes and forgot to open-source it, but they haven’t replied to my issue for 1.5 years now.

OnlyOffice is NOT fully open-source

Posted Apr 17, 2026 15:48 UTC (Fri) by pauly (subscriber, #8132) [Link]

There are more unencrypted HTTP only curl calls:
https://github.com/Euro-Office/core/pull/44
https://www.linkedin.com/pulse/onlyoffice-hidden-risk-doc...
Martin

onlyoffice tried to add stuff in the fine print, and failed

Posted Apr 20, 2026 14:23 UTC (Mon) by izumi_hsieh (guest, #183360) [Link]

About this situation, siding completely with the FSF. The entire drama is about section 7(b) and 7(e). Essentially, OnlyOffice added a modification to section 7(b), requiring that redistribution of the software retain the product logo, while the modification allowed in section 7(e) declines giving trademark rights to the product logo. If we take this, it means OnlyOffice is not open source at all, it would be what people are calling nowadays "source-available", you cannot distribute it at all, since you need to include a logo you don't have the rights to.

So, either this restriction is not valid, or we have an amazing blunder by the FSF, which wrote a license which could be manipulated to provide non-FOSS software. To see what happens, we need to read the license. Section 7(b) states

"Notwithstanding any other provision of this License, for material you add to a covered work, you may (if authorized by the copyright holders of that material) supplement the terms of this License with terms:

b) Requiring preservation of specified reasonable legal notices or author attributions in that material or in the Appropriate Legal Notices displayed by works containing it;"

It's about legal notices and author attributions, it doesn't cover trademarkable assets like product logos.

Furthermore:

'All other non-permissive additional terms are considered “further restrictions” within the meaning of section 10. If 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.'

So, the FSF has done its job well, the original license text already predicted this tricky maneuver. It's a good thing that this happened because it will discourage other companies from pretending they're open source when they are not.