Recently, The Document Foundation published an open letter to European citizens. We asked Euro-Office – the new coalition forming around a European alternative for productivity – whether ODF (the Open Document Format) would be its native document format. Unfortunately, we have not yet received a reply, and this confirms – at least in part – the suspicion that Euro-Office will join Microsoft’s allies in a strategy to lock in European citizens, who will see their content snatched away by a company that – in words only – presents itself as a defender of digital sovereignty. With the open letter, we have raised an issue that the general debate is not yet grasping: digital sovereignty is not determined solely by the terms of the licence and the location of the server, but by the format in which documents are created, stored and exchanged. We were able to pose our question publicly, with confidence, because we represent something extremely solid – support for the single open and standard format: ODF – which has been built up over twenty years by many people, whose names rarely appear in press releases. The foundations underpinning the political moment Germany has established by law that ODF