Source: OJ L, 2025/1140, 10.6.2025

Article 9 Designation to identify natural persons

Summary What does Article 9 of the RTS on record keeping say?

This article is notably technical in nature, setting out the precise methodology crypto-asset service providers must use to identify individual (natural person) clients in their records.

It builds directly on the broader record-keeping obligations established earlier in the regulation, providing the granular rules for how a person is actually coded and recorded.

The approach mirrors the client identification framework already used in financial markets regulation, specifically drawing on Delegated Regulation (EU) 2017/590, and adapts it to the crypto-asset context.

The core logic is to combine a country code with a nationally-specific identifier, with detailed rules to handle edge cases such as dual nationality, non-EEA nationals, and clients residing outside their country of nationality.

Important points:

Use a standardised identifier format for every individual client, combining their ISO 3166-1 alpha-2 country code with the highest priority national identifier available under Delegated Regulation (EU) 2017/590.
Where the CONCAT method applies, build the identifier from the client's date of birth, first five characters of their first name, and first five characters of their surname — all in upper case, with no special characters.
Where a client resides in a country different from their nationality, also identify that person based on their country of residence as set out in Field 41 of Table 2 of the Annex.

Springlex's summary of the article, a reading aid, not a substitute for the legal text.

1. A client who is a natural person shall be identified in the crypto-asset service provider’s records using the designation resulting from the concatenation of the ISO 3166-1 alpha-2 (2-letter country code) of the client’s nationality, followed by the national client identifier specified in Annex II to Delegated Regulation (EU) 2017/590, based on the client’s nationality.
1. The national client identifier referred to in paragraph 1 shall be assigned in accordance with the priority levels provided for in Annex II of Delegated Regulation (EU) 2017/590 using the highest priority identifier that a person has, regardless of whether that identifier is already known to the crypto-asset service provider.
1. For the purposes of identifying a natural person, if the person is a national of more than one European Economic Area (EEA) country, the country code of the first nationality when sorted alphabetically by its ISO 3166-1 alpha-2 code and the identifier of that nationality assigned in accordance with paragraph 2 shall be used.
1. Where a natural person has a non-EEA nationality, the highest priority identifier in accordance with the field referring to ‘all other countries’ provided in Annex II of Delegated Regulation (EU) 2017/590 shall be used. Where a natural person has EEA and non-EEA nationality, the country code of the EEA nationality and the highest priority identifier of that nationality assigned in accordance with paragraph 2 shall be used.
1. Where a client is a resident of a country other than the one of its nationality, crypto-asset service providers shall also identify that person based on the country of residence of the person as prescribed in Field 41 of Table 2 in the Annex.
1. Where the identifier assigned in accordance with paragraph 2 is based on CONCAT, the client shall be identified by the crypto-asset service provider using the concatenation of the following elements in the following order:
  1. the date of birth of the person in the format YYYYMMDD;
  2. the five first characters of the first name of the person;
  3. the five first characters of the surname of the person.
1. For the purposes of paragraph 6, prefixes to names shall be excluded and first names and surnames shorter than five characters shall be appended by ‘#’ so as to ensure that references to names and surnames in accordance with paragraph 6 contain five characters. All characters shall be in upper case. No apostrophes, accents, hyphens, punctuation marks or spaces shall be used.

Relevant recitals

Recital 5 Identifying decision-makers in algorithmic trading

Market abuse, including market manipulation, may be carried out through various means, including through algorithmic trading. Therefore, in order to ensure effective market surveillance, where investment decisions are made by a person other than the client or by a computer algorithm, that person or algorithm should be identified in the order and transaction records using unique, robust and consistent identifiers. For the same reasons, it is important to lay down that where more than one person in a crypto-asset service provider makes the investment decision, the person with primary responsibility for the decision is to be identified in the record.

Recital 6 Concatenated nationality-based natural person identifiers

To ensure unique, consistent and robust identification of natural persons in order and transaction records, those natural persons should be identified by a concatenation of the country of their nationality followed by identifiers assigned by the country of nationality of those persons. Where those identifiers are not available, natural persons should be identified by identifiers created from a concatenation of their date of birth and name.

Recital 7 Prioritised personal data identifiers for supervision

It is necessary that certain personal data are recorded by crypto-asset service providers to identify their clients or other natural persons relevant for orders or transactions in crypto-assets, as these data are fundamental to ensure efficient supervision by competent authorities, including in the area of market abuse. For all instances of identifying natural persons, this is to be done by following the level of prioritization of the different identifiers detailed in Annex II of Commission Delegated Regulation (EU) 2017/590(⁴).

Recital 8 Recording country of residence differences

It is possible that natural persons who need to be identified for recordkeeping purposes are residents of a country other than the one of their nationality. The country of residence of natural persons can affect several obligations under Regulation (EU) 2023/1114, and is therefore an important data element for ensuring effective supervision by competent authorities. Whenever their country of residence is different from that person’s nationality, this should be indicated by providing the country code of the country of residence of that natural person.

Table of contents

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