The digital safe, explained simply

What is a digital safe?

A digital safe is a secure preservation service that protects your electronic documents reliably and durably. Unlike a hard drive or standard cloud storage, it guarantees that each document remains unalterable, timestamped and retrievable throughout its retention period.

In France, it complies with a precise regulatory framework: the NF Z42-020 standard defines the functions of a "digital safe component". Its role is to provide technical proof of the date and integrity of each document, an essential condition for its probative value in case of dispute.

Digital safe deposit box or electronic archiving: what's the difference?

The two concepts are closely related but distinct. The digital safe (standard NF Z42-020) is a component: it seals and preserves individual documents with proof of integrity and timestamping. The electronic archiving system, or SAE (standard NF Z42-013), is a larger organizational and technical set that manages the entire lifecycle of the archive: submission, classification plan, final disposition, and traceability.

In practice, a digital safe is often the preservation component with probative value at the heart of an archiving project. To learn more, consult our electronic archiving guide and the electronic archiving glossary entry.

Evidentiary value: what makes the difference

The probative value is the ability of a document to serve as proof. It relies on four technical guarantees provided at the time of deposit.

The normative framework: NF Z42-020, NF Z42-013, and eIDAS

Three references structure preservation with probative value. The NF Z42-020 standard specifies the functions of a digital safe component; the NF Z42-013 standard (adopted in ISO 14641) governs the electronic archiving system as a whole.

At the European level, the eIDAS regulation defines qualified trust services, including qualified electronic timestamping, which provides a certifiable date that is enforceable against third parties. The eIDAS 2.0 revision extends this framework to the European digital identity wallet. Together, these texts establish the legal value of preserved documents.

When to use a digital safe?

The need arises whenever a document must be preserved in an enforceable manner, for a legal or contractual duration. The safe thus complements an electronic signature or HR dematerialization approach. A few common examples:

• Pay slips — the employer must offer a secure storage space to the employee (Labor Code).
• Signed contracts — preserve an electronic contract with probative value for the duration of its engagement.
• Invoices — archiving with probative value required by the electronic invoicing reform.
• Personal Documents — diplomas, documents, certificates kept secure and accessible for life.

Security and GDPR compliance

In a serious digital safe, each document is encrypted at rest with a key specific to the safe. Key management ideally relies on a hardware security module (HSM), which protects cryptographic secrets against any extraction.

The preservation of personal documents falls under the GDPR: data minimization, justified retention period, right of access and restitution. A compliant safe logs all access and ensures that only the holder, or an authorized person, can view or retrieve the documents.

Digital safe or cloud storage?

Cloud storage (Drive, Dropbox…) is designed for sharing and synchronization: files can be modified and deleted at will, without proof of their state on a given date.

A digital safe does the opposite: it seals, timestamps and makes each document immutable. The first meets a need for convenience; the second meets a need for proof and compliance. You can also verify the integrity of a signed document at any time.

How long should you keep your documents?

The retention period depends on the nature of the document and your legal obligations. A digital safe allows you to set, for each document, a period during which it remains immutable, then, if applicable, a controlled deletion. A few common guidelines in France:

Frequently asked questions

Also read