To use the services of KSEI, it is required to register as a service user and a securities account holder. The opening of a Securities Account at KSEI can only be carried out by Securities Companies, Custodian Banks, Issuers/BAEs, and KPEI.

KSEI will open a Securities Account, consisting of a securities and funds account, for Participants if they have met the requirements set by KSEI, hereinafter referred to as Account Holders.

Based on OJK Regulation Number 74/POJK.04/2017 concerning Securities Sub-Accounts at the Central Securities Depository and KSEI Regulation No. I-C concerning Securities Sub-Accounts, Account Holders who manage securities and/or funds on behalf of clients are required to open a Securities Sub-Account for each of their clients.

The purpose of opening a Securities Sub-Account is to separate the assets of the Account Holder from those of their clients, thereby preventing the misuse of client assets. Additionally, it provides investor protection and enhances efficiency in the distribution of corporate actions.