To ensure the OTC ISIN can be created, validated and returned to users near real time, the only validation the DSB performs on the underlying ISIN is syntactic validation. The onus is on the user to ensure the correct underlier is submitted for the correct template.

You should note that not all DSB ISINs that are created are being used for regulatory purposes, user have been creating DSB ISINs for internal use.

For full list of validations please refer to our DSB Product Definition documentation here