Tresorit is end-to-end zero-knowledge: not even the provider may read the files. Hosting in Switzerland, Ireland, Germany. ISO 27001, BSI C5, GDPR certifications. Encryption constitutes the absolute strength.
CadCamCloud is not zero-knowledge: the audit trail requires that the platform detect who accesses what and when, in order to generate the logs necessary in the event of a Ministry audit. Standard at-rest and in-transit encryption, controlled application access. The compliance logic is distinct: not "no party may read" but rather "every read is tracked, attributed, archived". EU hosting (Hetzner DE, Wasabi EU). Immutable PDF/A, structured audit log for every access.