I assume they hope that their added license condition of an ‘obligation to retain the original product logo’ is a ‘reasonable…author attribution’ (AGPL section 7b). Hmm.

They invite the FSF to judge:

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.

https://www.onlyoffice.com/blog/2026/03/interview-with-lev-bannov-ceo-at-onlyoffice-on-the-euro-office-situation