A customs certificate is not a qualified electronic signature certificate in the meaning of the Regulation (EU) No 910/2014 of the European Parliament and of the Council on electronic identification and trust services for electronic transactions in the internal market (eIDAS).
A customs certificate can be used to place an advanced electronic signature in the cases, in which the provisions of law permit to do so. Relevant information is provided in the descriptions of individual services available on PUESC.
Private keys (used to place a signature) are generated by the user and sent neither to PUESC nor to CCK MF. Therefore their recovery after deleting, loss of password, etc., is impossible. Only the user has access to the keys, provided that they are properly protected. When placing a signature, the keys are generated and operated by the CertSign application running locally on the user’s computer.
Since the electronic signatures identify the person, the signature certificates are assigned (issued) to the PUESC users rather than to the entities represented by these users. Identity of the entities is confirmed using the electronic seals.
Messages sent through PUESC can be authenticated using the electronic seal issued by CCK MF, representing the system/domain-specific service. This seal confirms the origin and integrity of a document.
Validity of the customs certificates is limited. This information is provided in a certificate. If the certificate is expired, the electronic signatures are verified as invalid. Therefore, signing the documents with a certificate, validity of which is about to expire, is not recommended.