Prove date and time with trusted time stamping

A timestamp mark is a date and time indication generated by a device or application, normally based on the system’s local clock. It may be useful operationally, but it does not provide enhanced legal guarantees or legal presumption It may be operationally useful, but it does not provide enhanced legal guarantees or legal presumption. A qualified time stamp, regulated by the eIDAS Regulation (Articles 41 and 42), is issued by a Qualified Trust Service Provider using secure cryptographic mechanisms and synchronization with official time sources (UTC). A qualified time stamp benefits from a presumption of the accuracy of the date and time and the integrity of the data throughout the European Union.

Time stamping makes it possible to prove that a digital document or data existed at a specific moment and has not been modified since then. It is commonly used in electronic signatures, electronic contracts, e-invoices, digital records, intellectual property protection, and audits or compliance processes.

Adding a qualified time stamp to an electronic signature makes it possible to objectively and verifiably prove the exact moment when a document was signed. Time stamping provides an independent, secure, and legally valid time reference, especially in contractual disputes, documents with legal deadlines, and deferred or multi-signer signature processes.

Lleida.net’s qualified time stamp can be integrated in different ways, depending on your company’s technical needs and level of automation. At user level, we offer ready-to-use time stamps that can be integrated directly into compatible electronic signature platforms, both desktop and enterprise. For enterprise environments and proprietary systems, we also offer integration through web services and HTTP protocol, enabling automated time stamping in internal processes and applications.

The use of time stamping is not mandatory in every case, but it is essential or highly recommended in processes that require authenticity, traceability, and reliable proof of date and time. There are procedures, especially in public administration, where time stamping is mandatory or recommended, such as submitting bids in public tenders, electronic registries, official notifications, and regulated administrative procedures.

Yes. Time stamping can be applied to any type of digital file or data, regardless of format, because it is not based on the file itself but on its digital fingerprint (hash).

A qualified time stamp remains valid as long as the cryptographic algorithms continue to be secure, the evidence can be correctly verified, and there are no changes requiring re-timestamping. For long-term preservation (more than 5–10 years), Lleida.net recommends periodic re-timestamping in accordance with ETSI EN 319 421, the use of LTA (long-term archival) profiles, and the preservation of complete evidence.

A Time-Stamping Authority (TSA) is the entity responsible for issuing time stamps that certify that a document, data item, or transaction existed at a specific moment. When the TSA is accredited under the eIDAS Regulation and audited according to ETSI standards, it is considered a Qualified Electronic Time-Stamp Service Provider. Lleida.net’s TSA is audited by AENOR in accordance with ETSI EN 319 403, 319 411, and 319 421, guarantees time accuracy, uses advanced cryptographic technology, and issues time stamps with full legal validity.

Yes. Re-timestamping consists of applying a new time stamp when the previous one is close to expiring, the cryptographic algorithms need to be updated, or the document must be preserved for long periods. Re-timestamping makes it possible to maintain legal validity and the chain of trust in accordance with the cryptographic longevity set out in ETSI EN 319 421.

Yes. Time stamping makes it possible to prove that digital content existed on a specific date. It can be applied, for example, to literary works, source code, industrial designs, photographs, inventions, or technical documents. This makes it possible to prove authorship, creation, and prior existence, which can be key in court proceedings, audits, or intellectual property registrations.