Is a simple electronic signature legal? What eIDAS really says

Yes, a simple electronic signature can have legal effect and can be admitted as evidence. But that answer needs an important nuance: not all electronic signatures carry the same evidentiary weight, nor are they suitable for every document.

The European framework governing this matter is the eIDAS Regulation. Its Article 25.1 establishes that an electronic signature cannot be denied legal effect or rejected as evidence in judicial proceedings solely because it is electronic or because it does not meet the requirements of a qualified signature.

This also protects a simple electronic signature, known as SES. A signature drawn on a screen, a name typed at the end of a document, or a clear acceptance action can fall within this category.

Informational content, not legal advice. Requirements may vary depending on the document and the specific case.

"Has legal effect" doesn't mean "works the same for everything"

Article 25.1 is a non-discrimination rule. It prevents evidence from being dismissed simply because it's electronic, but it doesn't guarantee that any digital scribble automatically proves who signed, what they accepted, or whether the document was modified afterward.

In case of a dispute, you need to be able to answer questions like these:

• Which exact document was shown to the signer?
• Did the person clearly express the intent to sign?
• How does the action relate to that person?
• When did it happen?
• Has the content remained intact after signing?
• Is a consistent record of the whole process kept?

That's why it's worth distinguishing three concepts:

• Validity: whether the agreement meets the applicable legal requirements.
• Admissibility: whether the document and signature can be presented as evidence.
• Evidentiary weight: how convincing that evidence is if someone challenges it.

An SES can be perfectly useful, but its value increases when it's part of a well-documented process.

What evidence strengthens an SES?

There's no magic data point. Strength comes from the combination of evidence:

1. Explicit consent. The signer must see what they're accepting and perform an unambiguous action, such as checking a box and pressing Sign and accept.
2. Exact version of the document. The specific PDF or content that was presented must be kept.
3. Integrity. A cryptographic hash makes it possible to check whether the bytes of the stored document match those from the moment of signing.
4. Date and time. The timestamp places the action in time. A qualified timestamp offers stronger guarantees, but shouldn't be confused with a simple date saved by the system.
5. Traceability. The recipient's email or phone number, the link identifier, process events, the version of the terms, and other contextual data.
6. Authentication proportionate to the risk. A link sent to a known channel, a one-time code, or an identity check can strengthen the connection to the signer.

An IP address can provide context, but it doesn't identify a person on its own: it can be shared, dynamic, or belong to a corporate network. Similarly, a drawn signature is a visual manifestation, but it isn't a biometric verification by default.

When does a simple electronic signature usually fit?

SES tends to be a proportionate choice when the risk is low or moderate, the parties already know each other, and no rule requires a higher form. For example:

• authorizations to participate in activities;
• everyday informational consents;
• internal confirmations;
• acceptance of an organization's rules;
• simple agreements between known parties;
• receipt or acknowledgment of documents.

Looking at the document's title isn't enough. A simple authorization for a school trip doesn't carry the same risk as a complex medical consent, even if both contain the word "authorization."

When should you raise the level of assurance?

Consider an advanced or qualified signature, or specific legal advice, when:

• sector-specific law imposes concrete requirements;
• large amounts or hard-to-reverse consequences are involved;
• the signer's identity is likely to be disputed;
• public administrations, registries, notaries or regulated entities are involved;
• legal representation must be proven with particular rigor;
• the recipient expressly requires a certificate or specific level.

The right question isn't just "is it legal to sign electronically?" but "what level of evidence does this specific document need?"

What does Sygnau offer?

Sygnau is designed to make everyday authorization and signature-collection processes easier, reducing paper, manual follow-up and lost documents. In SES-based flows, the value isn't just drawing the signature: it's also keeping the accepted document and the available process evidence properly organized.

Before using any solution, check that the signature and identification level is appropriate for your case. If a rule requires an advanced signature, a qualified signature, notarial intervention, or a specific formality, an SES does not replace it.

Sources

• Consolidated eIDAS Regulation — EUR-Lex
• eSignature FAQ — European Commission
• Law 6/2020 on electronic trust services — BOE

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