Who actually has access to the data?
Each recipient gets a one-time link with configurable lifetime. The recipient is known by name in the system; every access is attributed to a person — even for external addressees without a Conbool account.
Access is classically by username and password (or SSH key for SFTP). In practice credentials are often shared between multiple staff on the partner side — who actually downloaded a file is usually not provable at application level.
Source: generic property of the FTP / SFTP protocol. FTP is specified in RFC 959; SFTP runs over SSH as defined in RFC 4251–4254 and is itself documented only as an IETF draft. Shared functional accounts are a common finding in security audits and addressed as a risk in the German BSI IT-Grundschutz baseline.