No, federation alone doesn't solve the problem. This is addressed in the third paragraph of the paper; the TLDR is that federated processing might still leak pe

No, federation alone doesn't solve the problem. This is addressed in the third paragraph of the paper; the TLDR is that federated processing might still leak personal information: > The adoption of FA in the medical sector, despite its potential, has been slower than expected. This is in large part due to the unresolved privacy issues of FA, related to the sharing of model updates or partial data aggregates in cleartext. Indeed, despite patient-level data not being transferred between the institutions engaging in FA, it has been shown that the model updates (or partial aggregates) themselves can, under certain circumstances, leak sensitive personal information about the underlying individuals, thus leading to re-identification, membership inference, and feature reconstruction. Our work focuses on overcoming this key limitation of existing FA approaches.