Hellenic Exchanges (HELEX) is the organization responsible for the clearing and settlement of the Athens Exchange transactions and administration of the Dematerialized Securities System (DSS). In DSS all dematerialized securities are recorded and transfers are monitored through the Investors Shares and Securities Accounts kept in DSS.

Participants in the clearing and settlement procedure are the Operators of DSS - the Members of ATHEX and the Custodian banks.