Euro-Office forked OnlyOffice for digital sovereignty and landed in a licensing dispute.
How can you tell whether an open-source project is truly open? Don't read the README. Read the license.
A European consortium just forked OnlyOffice to build "Euro-Office", a sovereign alternative to Microsoft 365 backed by Ionos, Nextcloud, and several partners. Within days, OnlyOffice publicly accused the project of license violations. Before a single stable release, Euro-Office is fighting a legal battle.
The technical decision was sound. OnlyOffice has a modern, web-native architecture with strong Microsoft document compatibility, arguably a better starting point than LibreOffice. The consortium saw an opportunity, forked the code, and started building.
But they stripped the OnlyOffice branding from the interface. And that is where everything fell apart.
OnlyOffice uses the AGPL v3 license with additional terms requiring any derivative work to retain the original product logo. Remove it, and you are in breach; not of a gentleman's agreement, but of enforceable license conditions tied to intellectual property law.
The consortium disagrees, arguing forks are a fundamental right in open source. The Free Software Foundation and Bradley Kuhn, the creator of the AGPL, both support their legal interpretation.
So who is right? That is the wrong question.
The real question is why a consortium of major European technology companies walked into this trap. The codebase was audited. The architecture was evaluated. But the legal foundation was not stress-tested with the same rigor; and now the project's credibility is on the line before it even ships.
This is what the digital sovereignty movement keeps running into. Self-hosting infrastructure, forking code, breaking free from Big Tech; those are the right goals. But sovereignty is not just a technical problem. It is a also a legal one. If the license terms of the code you forked can be weaponized against you, you have just traded one dependency for another.
There is also another layer. OnlyOffice was originally developed with a Russian IT firm. After 2022, the company restructured through Singapore, the UK, and Latvia. For a project branded around European sovereignty, that geopolitical history adds risk beyond license compliance.
Compare this to how license architecture shapes outcomes. The MPL-2.0 license, used by Collabora Online, is file-level copyleft, not project-level. Fork, rebrand, integrate, no IP exposure across your stack. This dispute could not have happened under that structure.
If the legal foundation is not as robust as the technical one, you are building on sand.