What would happen if the ownership of securities were recorded in a blockchain? We envisage two scenarios for the integration of this technology in the post trade world. The first scenario creates a total disruption. In its purest form, a distributed blockchain system allows all market participants direct access to the DSD (Decentralised Securities Depositary), to the exchange and to the post trade infrastructure (clearing & settlement).  The second scenario is an integration within the post trade ecosystem. The distributed ledger might only be the next generation of IT infrastructure. In this scenario custodians or settlement infrastructures might use the blockchain to record the ownership and trades between themselves; however end investors will still need to use a custodian to have access to the market. The ledger will only be accessible to authorised market participants.

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