Time Stamping Authority

A Trusted Service Provider that provides time stamp services is called Time Stamping Authority (TSA). It has the general responsibility for the provision of its Time Stamping services, covering the operation of one or more time stamping units. Each Time Stamp must identify the responsible Time Stamping Authority, through its signature.

The Time Stamping Authority provides certainty about the pre-existence of data in electronic format at a specific time, and that those data have not been altered since that specific time.

ANF Certification Authority, as a Qualified Trust Service Provider, which provides Qualified Electronic Time Stamping Service, is considered a Time Stamping Authority.

Service of issuance of Qualified Time Stamps

ANF AC as a Qualified Trust Services Provider, has, among its portfolio of qualified trust services, the service of issuing Qualified Electronic Time Stamps. https://webgate.ec.europa.eu/tl-browser/#/tl/ES/5

The consumption of the service does not require any integration by the customer, nor engineering hours to start its consumption. ANF AC makes available to the customer a web service from which the request for Qualified Time Stamps must be made, through the credentials granted by ANF AC.

Properties of the
qualified time stamp


Legal Evidence
The Qualified Electronic Time Stamp, has throughout the EU, the presumption of precision of the date and time indicated and the integrity of the data to which they are linked to that date and time. The issuers of these instruments are based on a precise source of time linked to coordinated universal time (UTC).

The Qualified Time Stamp will be accepted for legal purposes and may not be denied or inadmissible as evidence in legal proceedings.


Date Accuracy
The accuracy of the date and time indicated on the qualified time stamp is ensured.


Does it mean to prevent the alteration of the document?
A qualified time stamp guarantees that an alteration can be detected, but does not provide a guarantee that this alteration will not occur. That is, it does not prevent the alteration of the sealed content, but it will be possible to know with certainty if said content has been modified or altered.

Use cases

Use cases given taking into account that qualified time stamps ...

  • They enjoy the presumption of precision of the date and time they indicate and the integrity of the data to which they are linked.
  • That exact moment in time can be safely validated by all parties that have access to the data and the time stamp.
  • This guarantee of the exact moment in time associated with the document or data with time stamp, can cover a very long period of time

These properties allow different types of use that can be applied in thousands of real cases, some of them can be:

  • Establish the time in which a document is signed.
  • Establish the time of issuance of a document.
  • Establish the moment in which a contract ends.
  • Enforce time limits and deliveries.
  • Resealed electronic documents that incorporate electronic signature for long-term custody.
  • Legitimize the exact chronology of events.

    To manage your request, ANF AC requires your personal data. In accordance with current legislation on data protection, we inform you,

    Controller ANF Certification Authority, ANF AC.
    Purpose Registration and management of requests or queries for information related to Time Stamp.
    Rights You have the right to information, access, rectification and erasure, object, restriction and data portability. See additional information.
    Additional Information https://www.anf.es/en/politica-de-privacidad/

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