Open source communities attract people with their appeal, as while some projects may be supported by financial interests, this is not the general rule. Other motives include a sense of community, social goals, gaining experience, and the desire to avoid dependence on proprietary solutions. Nevertheless, some view the nature of open code as 'free-for-all.'
This implies that 'I can do whatever I want with it' or 'I think there won't be any problems if I use this software in this way.' However, established rules exist in the world of open code. If these rules are combined with a degree of common sense, it is ideal. Otherwise, the consequences can go beyond mere annoyance.
Perhaps I am stating the obvious, but sometimes the obvious needs to be said. Three relatively recent events discussed here in Tecnoblog illustrate how problematic non-compliance with the terms of open-source projects or related principles can be. We will examine each of them to understand what we can learn.
Notepad++ is a text and code editor released in 2003 by developer Don Ho and still maintained by him. It is a fairly well-known utility because it is lightweight, allows editing various programming languages, has open source, and costs the user nothing.
However, Notepad++ is only available for Windows. Therefore, some users were pleased with the release of this utility's version for macOS this April. The new project repository initially featured 'Notepad++' as the official name, used the software's logo, and listed Don Ho's name among the responsible parties. But it soon became clear that Ho had not released Notepad++ for Mac and had not authorized anyone else to do so on his behalf.
After a warning from the community, Don Ho took several steps to resolve the issue, including asking Andrey Letov, the true author, to change the project's name and logo. Letov resisted. Initially, he claimed he only wanted to offer a Notepad++ version for Mac users and hoped Ho would approve it. But under pressure from Ho and the community itself, Letov agreed to make changes: Notepad++ for Mac was renamed Nextpad++, received its own domain and logo, and mentions implying Don Ho's involvement in the project were removed. Recently, the editor also received a version for Linux.
Some may have a different view, but this is not the case. Notepad++ is distributed under the GPL 3.0 license, which permits free use, access to the source code, and the creation of derivative works (forks). However, this license does not transfer trademark rights used in the project to the user.
This was Andrey Letov's biggest mistake: he could not assume that the GPL license also gave him permission to use the name and symbol Notepad++ as a brand for his project. Furthermore, Letov associated Don Ho's name with the new software without consulting the developer about it.
But could Ho have accepted the invitation, even if belatedly? He could. But he gave convincing reasons for refusal: '(...) I cannot be responsible for the long-term maintenance of an adapted version or fork that I do not manage. Any critical issues, failures, or vulnerabilities in this external project could damage the reputation of Notepad++ itself.' - Don Ho.
This is a case where the 'wrong' side is not what we first look at. Euro-Office was announced in March 2026 and presented in June as an open office suite promoting the digital sovereignty of the European Union. The project was based on an existing open solution—OnlyOffice—and this was never a secret. Nevertheless, those responsible for Euro-Office were accused of intellectual property infringement and licensing violations.
The essence of the accusation was that OnlyOffice has additional clauses in its project license (AGPL-3.0) requiring the preservation of its visual identity and authorship attributions in derivative software. However, Euro-Office removed logos and other references to OnlyOffice from its interfaces. It seemed that the Euro-Office team acted in bad faith. But the counterargument was consistent: Nextcloud, one of the organizations running the project, stated that Section 7 of the AGPL-3.0 license provides for the removal of additional restrictions that create obstacles to the use or distribution of the code.
In this case, the conflict lies in Euro-Office's obligation to display a brand belonging to a third party. According to Nextcloud, this situation puts Euro-Office in contradiction with AGPL-3.0, so this clause can be removed according to the license regulations to mitigate the violation.
Who is right? There is no court ruling or anything similar to definitively conclude the discussion. However, Bradley M. Kuhn, one of the AGPL custodians, classified Ascensio's position (the organization controlling OnlyOffice) as 'the most ingenious additional restriction I have seen.' This is because if an additional project clause requires retaining the original logo, a second clause prohibits third parties from using that brand—this is a real contradiction.
Even the Free Software Foundation (FSF) spoke out in support of Euro-Office: 'This obligation to 'retain the original product logo' is not included in Section 7(b) (A)GPLv3 (...), therefore, it is considered an additional restriction. (A)GPLv3 clearly states that it allows all licensees to remove any additional conditions that are 'additional restrictions' under (A)GPLv3.' - Krzysztof Siwiec, FSF Licensing and Compliance Manager.
Euro-Office is involved in other disputes (for example, it was called a 'partner' by the Microsoft LibreOffice team), but at least this case seems to be moving toward a resolution: Ascensio proposed requiring that OnlyOffice be mentioned only in relevant parts of the source code and in end credits, which is a standard approach in open-source projects.
Even small projects need protective measures. The OpenMandriva case is a good example. It was created in 2012 after Mandriva Linux ceased to exist, and its continuity was almost threatened due to a conflict between employees.
David Beatrice, known for supporting the Mumble voice messaging application, proposed a private instance on OneDev to host the Linux distribution repositories when he joined the OpenMandriva team. While this solution would eliminate potential hosting costs on GitHub or provide redundancy, it would also leave critical infrastructure in the hands of one person. Although some members expressed this concern, the proposal was accepted.
Everything went well until another employee who joined the project with Beatrice began exhibiting aggressive behavior towards other members, according to the moderator 'AngryPenguin'. As a result, this person was banned from one of the main project chats by AngryPenguin himself (but remained part of OpenMandriva). Disagreeing with this decision, Beatrice decided to leave the initiative. Consequently, the distribution moderators decided to unhook the mirror repositories on the OneDev instance. Beatrice became even more upset and, therefore, using his access privileges to the instance, deleted certain repositories and published an empty package, 'which obsoleted all Gnome and Cosmic packages,' reported AngryPenguin.
In The Register, David Beatrice admitted to intentionally deleting the repositories and making the packages obsolete but denied any attempt at sabotage. His goal was protest after the moderators deleted OneDev configuration files from several repositories without his consultation. A few days after the initial report, OpenMandriva announced that the deleted repositories had been restored and the problematic package removed. Thus, the project returned to having repositories on GitHub, independent of personal accounts. Backups saved by other employees proved vital for returning to normal. Without them, the troubles would have been much more serious.
I am not one of those people who believes we should learn from everything that happens to us. But it cannot be denied that the cases examined offer valuable lessons that emphasize that open source is a serious topic. In conclusion:
The main message is this: open source opens doors for study, exchange, and the creation of derivative products based on original projects, provided that the terms of each license are observed. Otherwise, we risk falling into the old and dangerous cliché of confusing freedom with permissiveness.