Changes in ISIN code

On 29 April 2019, in connection with migration of the original system for management of ISIN/CFI/FISN codes to the main information system, CDCP adopted also changes in generating of ISIN codes. Codes allocated before this date remain valid and shall not be impacted by the change.

In previously generated ISIN code the second and third position after the „SK” prefix denotes also form and type of security. However, these qualifiers became irrelevant due to allocation of CFI and FISN codes. Structure of the ISIN code has been changed from 29 April 2019 and in CDCP the first number after the “SK” prefix specifies category of security/financial instrument in compliance with ISO 10962 (CFI). The number „1” next to the „SK” prefix represents equity securities. In CDCP these are mainly shares, temporary certificates and co-operative units. Number „3” after the „SK” prefix signifies collective investment instruments. In CDCP it means primarily units of unit trusts. The „SK” prefix followed by number „4” signifies debt securities. In CDCP these are firstly bonds, covered bonds, treasury bills and investment certificates. Other types of financial instruments are identified with number „0” after the „SK” prefix.

Category (type) of security: 


Equity securities (e.g. shares)


Collective investment instruments (e.g. units of unit trust)


Debt securities  (bonds, treasury bills, investment certificates)


Other types of securities / financial instruments

The change itself didn’t impact the client considerably. But it may cause concerns regarding correctness of the ISIN code, as a client issuing bonds has been accustomed to the identifier SK411 or SK412 until now. This identification was changed and consists of abbreviation SK and number 4 for category of a security.

Changes were implemented also in new application forms for allocation of ISIN. New forms are more simple and transparent compared to the original form, thus it takes less time for the client for fill in the form. Thanks to new forms and the fact that ISIN/CFI/FISN codes are managed through the main information system, CDCP is able to allocate the codes in shorter time, most often on the day following placement of valid request.

CDCP as the National Numbering Agency and member of the Association of National Numbering Agencies (ANNA) allocates security identifiers ISIN, CFI and FISN. Form of ISIN, CFI and FISN is set by the technical standards ISO 6166, ISO 10962 and ISO 18774.

Author: Peter Nagy

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