262. In the Consultation Paper, ESMA proposed two alternative proposals with regards to the format of client codes, with the first one aligned with the CDE guidance and the second one following the provisions of MiFIR transaction reporting.

263. The CDE guidance provides a format in which client codes should be reported as "LEI of Reporting Counterparty + Internal Identifier of Individuals", while the alternative proposal is to replace the Client Code with the National Client Identifier.

264. In response to the consultation most of market participants agree with ESMA's proposal to use the client code format indicated by the CDE guidelines, pointing out that the use of National Client Identifier would arise data privacy issues. One respondent suggested reporting the National Client Identifier which would be masked at the TR level and the information on client's national code would be provided to NCAs only on request. While ESMA in principle does not foresee data privacy issues due to reporting the National Client Identifier to TRs to comply with the reporting requirements introduced pursuant to the Article 9 of EMIR, such approach would not solve the data privacy issues (if any) along the reporting chain and would result in a more onerous process for the TRs.