Signature levels

Every signature in AssinaJá carries a legal weight. That weight is set by the eIDAS regulation, which defines three levels. Choosing a level is really choosing how hard it would be for a signer to later deny having signed.

The three levels

SES Simple Electronic Signature

Admissible in court but may be contested. Used for low-risk acceptance flows (e.g. acknowledgements, internal sign-offs).

AES Advanced Electronic Signature

Strong presumption of validity under eIDAS Art. 26. Uniquely linked to the signatory, tamper-evident, and under sole control of the signer.

QES Qualified Electronic Signature

Legally equivalent to a handwritten signature across the EU under eIDAS Art. 25.2. Issued by a Qualified Trust Service Provider listed in the EU Trust List.

The practical difference is who carries the burden of proof. With SES, you must prove the signature is genuine if it is challenged. With QES, the signer must prove it is not.

Identity verification

The level is only half of it. The other half is how confident the platform is that the signer is who they claim to be — shown in the app as Identity assurance.

Level	What it means
Low	Self-declared identity (email or link only).
Substantial	Remote verification (SMS OTP and/or ID document number).
High	Strong identity verification (national eID such as Chave Móvel Digital, or in-person).

A signature cannot be stronger than the identity check behind it. This is why Chave Móvel Digital reaches QES while a drawn signature does not, however careful the signer was.

Signature types you can choose

These are the options offered when you add a signer to a document.

Option in the app	Level	Identity
Visual Signature	SES	Low
Visual Initials	SES	Low
Visual Signature + OTP SMS	SES	Substantial
Visual Signature + ID Confirmation	SES	Substantial
Mobile Digital Key	QES	High
Digital Mobile Key with Attributes	QES	High
Receives Copy (cc)	—	—

Receives Copy (cc) is not a signature. Someone added this way receives the document for information and is never asked to sign.

There is no AES option to assign to a signer. The mapping that drives the badges recognises exactly six types — Simple, SimpleInitials, OTPSMS, IdConfirmation, CMD, CMDSCAP — and returns no level for anything else. The Digital Certificate label in the app’s string table does not correspond to an assignable level.

That does not mean you are missing something. eIDAS Art. 3.12 defines a qualified signature as an advanced electronic signature created by a qualified device and based on a qualified certificate: every QES is also an AES. Choosing Chave Móvel Digital does not skip the advanced level — it goes past it.

It is also why you will find texts describing CMD as “advanced”: they are quoting the opening of the qualified definition.

The AES that genuinely exists on the platform is a different thing: the certifying seal applied to every document, issued by an AATL authority. It is not chosen per signer because it is not the signer’s — it is the platform’s.

See Qualified signatures with CMD.

Choosing a level

Match the level to what you lose if the signature is successfully denied.

Internal approvals, acknowledgements, low-value sign-offs — SES is proportionate.
Commercial contracts with an external party — add OTP SMS or ID confirmation, so identity is verified rather than merely asserted.
Anything with a statutory form requirement, or where handwritten-signature equivalence matters — use Chave Móvel Digital. It is the only option that is legally equivalent to signing by hand across the EU.

Digital Mobile Key with Attributes additionally proves a professional capacity — that the signer is acting as a lawyer, accountant, or company representative, not merely as themselves.

Qualified signatures with CMD — how it works, and what professional attributes add
Legal validity — what each level is worth as proof
Document lifecycle — the states a document moves through once sent
Send a document for signature