Firstly, I trust that there is already a daily transactional reconciliation perform for each movements i.e recepipt/deliver/registration/corporate actions processing.
What this means , is that before any trades/corporate actions/registration are processed, a check on the availability of shares are performed between NCS and TSD or any external system. This transactional check at individual line of activities is the mitigating process should there by issue/failure with the daily positions reconciliation.
Below is an extract of the Guideline provided by Group on stock reconciliation. At the minimum there should already be a weekly reconciliation performed on total holdings by line of stocks with the depository and NCS.
Scripless
Stock
Reconciliation 1. Security balances as per the depository records should tally with the
records within the processing system (NCS, CCS, and RCS) on an
automated basis (where possible).
• All activities based on transaction in/out movements of stocks are to be reconciled on a daily basis.
• The total holdings as per the processing system are to be reconciled with that of depository records, by individual line of stocks on a weekly basis.
• (If the local central depository provides data by individual client account) the total holdings as per the Processing system is to be reconciled with that of central depository records, at individual client account level otherwise at least on a monthly basis. (If the local central depository does not provide data by individual client account), the reconciliation by individual line of stocks suffices.
• Where regional hub services are offered, the records of the hub and the local centre should be reconciled on a weekly basis.
• Any issue relative to scripless stock reconciliation must immediately be escalated as per Escalation Matrix..