Electronic time stamping: definition and use

Time stamping in a nutshell

Time stamping in a nutshellElectronic time stamping(timestamping) links a digital document to a precise date and time, in a verifiable and tamper-proof manner. It is proof that a document existed at a given time — a decisive argument in the event of a dispute over the date of an engagement.

Why timestamps are crucial

Without timestamps, it is impossible to prove:

• whether a contract was signed before or after a key event
• who last modified the document
• whether the date written in the document corresponds to the actual signature

For a 50 contract 000 € signed on December 30: for the current fiscal year or the next?

How a timestamp works

The standard process relies on aThe standard process relies on athird-party time stamp

1. (TSA) which:
2. Receives the cryptographic fingerprint of the document
3. Adds the precise date and time (NTP clock)
4. Signs the whole thing with its own keyReturns a

timestamp token

This token is embedded in the PDF in PAdES format. Anyone can then verify the date and integrity.

Simple vs qualified timestamping

• eIDAS distinguishes two levels:Simple ⬥⬥⬥: any service provider. Useful proof but without legal presumption.
• Simple ⬥⬥⬥: any service provider. Useful proof but without legal presumption.Qualified ⬥⬥⬥: QTSP registered on the trusted list. Legal presumption of reliability (article 41 eIDAS).

For high value documents, qualified timestamp is recommended.

When to use timestamps

Timestamps are systematic in a modern electronic signature. But certain situations require particular vigilance:

• Calls for tenders (deadline for submission)
• Intellectual property (date of creation)
• Contracts with high tax implications (accounting year)
• Transfers of shares (date of transfer)
• Regulatory filings (CNIL, ACPR, AMF)

Proof of existence and integrity

The timestamp proves two things:

1. The timestamp proves two things:Existence ⬥⬥⬥: the document existed on the date T
2. Integrity ⬥⬥⬥: no modification since THow to check a timestamp

Adobe Reader → signature properties → third party timestamp details. Displays TSA name, exact date, validity status. Tools like pdfsig allow command line verification.

How Certyneo helps you

All Certyneo signatures include a timestamp in PAdES format. For cases that require qualified timestamping, we interface with European eIDAS-qualified TSAs.

Discover the Certyneo electronic signature solution

FAQ

Is a system timestamp enough?

No. A local timestamp can be modified. Only a trusted third party has probative value.

Do I have to pay for a qualified timestamp?

Do I have to pay for a qualified timestamp?

Usually included in professional plans of signing platforms.

Does the timestamp expire?

The token does not expire, but its long-term validity depends on the algorithms. Use PAdES-LTA for multi-decadal validity.

Does timestamp replace signature?

No. Signature identifies the author, timestamp proves the moment. Complementary.

Can I time stamp without signing?

Yes, to prove the existence on a date (digital INPI filing, proof of anticipation).

Conclusion

Timestamping is the safety belt of the electronic signature: invisible on a daily basis, essential in the event of an accident.

Try Certyneo to send, sign and track your documents online simply, quickly and securely.