Signature Verification: Resemblance, Authenticity, and Notarial Limits

This article answers

• What is the difference between signature verification by resemblance and by authenticity?
• Does signature verification certify the validity of the document's content?
• What is the liability of the civil-law notary office in signature verification?
• How does the procedure for signature verification by authenticity work?
• What documents are required to perform signature verification?

In summary

• Signature verification (reconhecimento de firma) is a notarial declaration with public faith certifying the authorship of a signature on a private document.
• Verification by resemblance compares the handwriting style with the signature card archived at the notary office (cartório).
• Verification by authenticity requires the physical presence of the individual and an in-person signature before the notary or notary clerk.
• The act certifies only who signed the paper. It does not analyze the content of the page nor certify the validity of the underlying legal transaction.

What is the difference between signature verification by resemblance and by authenticity?

Signature verification (reconhecimento de firma) has two main modalities in Brazilian notarial law. Each meets specific legal requirements and provides different levels of formal verification.

In signature verification by resemblance (reconhecimento de firma por semelhança), the civil-law notary office (tabelionato de notas) performs handwriting comparison. The notary clerk compares the signature on the private document with the image stored in the signature file (signature card / cartão de autógrafo). The individual does not need to be physically present at the notary office at the time of the act. Anyone can bring the paper to the service counter to obtain notarial validation.

In signature verification by authenticity (reconhecimento de firma por autenticidade), the physical presence of the signatory is mandatory. The citizen appears in person at the notary office carrying an official identification document. They sign the document in the presence of the clerk and sign a ledger of authenticity terms (livro de termo de autenticidade). This type of act is required by express regulation in transactions such as vehicle title transfers (CRV/ATPV-e) or high-value contracts.

| Feature | Verification by Resemblance | Verification by Authenticity |

| :--- | :--- | :--- |

| Physical presence | Optional | Mandatory |

| Verification method | Visual comparison with signature card | Personal identification and in-person signature |

| Ledger signature | Not required | Requires signature in the terms ledger |

| Common use | General contracts and simple powers of attorney | Vehicle transfers and higher-risk transactions |

The notary's authority to certify signatures stems from Lei nº 8.935/1994 (Lei nº 8.935/1994 - Notary and Register Act, art. 6º). The primary objective of the service is to provide publicity, authenticity, and effectiveness to private documents (Lei nº 8.935/1994, art. 1º).

For remote procedures, you can also use digital signature verification via the e-Notariado platform.

Does signature verification certify the validity of the document's content?

Signature verification (reconhecimento de firma) certifies solely the authorship of the signature stated on the page. It does not confer legal validity upon the contract text, nor does it attest to the legality of the obligations described therein.

There is frequent confusion between the act of verifying a signature and drafting a public deed (escritura pública). When executing public deeds, the civil-law notary (tabelião de notas) examines the legal capacity of the parties, the lawfulness of the subject matter, and the compliance of the transaction with the Código Civil (Lei nº 10.406/2002 - Brazilian Civil Code, art. 215). In the act of authenticating a signature, the notary office does not draft or approve the content of the private document.

If a contract contains void or illegal clauses, the notarial act on the signature does not cure these defects. The requirements for the validity of a legal transaction involve a capable agent, a lawful object, and a form prescribed by law (Lei nº 10.406/2002, art. 104).

By affixing the seal and stamp of signature verification, the notary office merely declares: "this signature belongs to the indicated individual." The notary office is not liable for non-compliance with the contract or for contractual fraud devised by the parties.

What is the liability of the civil-law notary office in signature verification?

The civil and administrative liability of the civil-law notary (tabelião de notas) is delimited by the type of act performed. The notary office is liable for damages resulting from failures in identification or handwriting comparison.

In signature verification by resemblance, liability depends on whether the visual comparison was conducted with due technical diligence. If the clerk validates a signature that diverges from the signature card due to negligence, the notary office can be held liable. However, if the forgery is undetectable to a layperson and to a standard notarial technician, the agent's fault is ruled out.

In signature verification by authenticity, the notary office's duty focuses on verifying the individual's identity. The notary office must inspect the presented identification documents, check for signs of tampering, and collect the signature in the appropriate ledger.

Notarial liability does not extend to the following aspects:

• Settlement of financial installments agreed upon between private parties.
• Actual ownership of personal or real property mentioned on the paper.
• Mental capacity of the signatory when there is no obvious incapacity.
• Defects of consent, such as coercion or errors in drafting contract clauses.

The Conselho Nacional de Justiça (National Council of Justice - CNJ) and the Corregedorias-Gerais de Justiça (State Judicial Inspectorate Offices) establish guidelines so that notary offices maintain verification standards without intruding upon the private autonomy of the parties (Provimento CNJ nº 149/2023, Livro II - CNJ Regulation No. 149/2023, Book II).

How does the procedure for signature verification by authenticity work?

The procedure to perform signature verification by authenticity requires structured in-person steps to ensure legal certainty.

• Document preparation: Bring the private document printed and in good condition. Do not sign the page before standing at the service counter of the notary office.
• Presentation of personal ID: Present an original, official identification document with a recent photo to the clerk.
• Opening or updating the signature card: If you do not have a file at the notary office, the clerk will create your record with personal data and biometric registration.
• In-person signature: Sign the private document in the direct presence of the notary or responsible notary clerk.
• Signing the Authenticity Term: Fill out and sign the page of the authenticity terms ledger maintained at the notary office.
• Payment and affixing the seal: Pay the emoluments set by the official state fee table and receive the page stamped with the notarial seal.

If an individual needs to grant powers to third parties to sign acts on their behalf, a public power of attorney (procuração pública) should be used.

What documents are required to perform signature verification?

To request signature verification, the user must present basic identification documentation.

• Official identification document with photo (Identity Card - RG, Driver's License - CNH, Passport, or Professional ID Card).
• Individual Taxpayer Registry card (CPF - Cadastro de Pessoas Físicas).
• Updated Marriage Certificate (required in specific cases of name changes).
• The original private document that will receive the notarial seal.

For corporate entities requiring representation by directors or partners:

• Updated Articles of Incorporation or Bylaws (Contrato Social or Estatuto Social).
• Minutes of the election of directors registered with the competent authority.
• Corporate Taxpayer Registry card (CNPJ) issued from the Federal Revenue website.

The emoluments charged for performing signature verification are fixed by state law. Consult the official fee schedule in effect in your state to check the applicable amounts for the act.

Document checklist

• [ ] Official photo identification document with recent photo
• [ ] Active CPF card with the Federal Revenue Office
• [ ] Original private document without alterations or erasures in the signature field
• [ ] Proof of legal representation (if signing on behalf of a company)
• [ ] Active signature card (for the resemblance modality)

In practice

Case 1: Vehicle sale with verification by authenticity

Carlos sold a used car to Roberto. To complete the transfer, the traffic department requires signature verification in the authenticity modality on the Vehicle Registration Certificate (CRV). Carlos went to the notary office with his driver's license (CNH). Before the clerk, Carlos signed the seller's section. The clerk collected Carlos's signature in the authenticity ledger and affixed the corresponding seal. The notary office guaranteed the seller's identity, protecting both parties against identity fraud.

Case 2: Rental agreement and limits of liability

Mariana signed a residential lease contract and took the paper to the notary office to perform signature verification by resemblance. Months later, the tenant stopped paying rent. Mariana questioned the notary office about the validity of the contract guarantees. The notary office clarified that the notarial stamp certified only that the tenant's signature matched the registered signature card. The notary office did not guarantee the tenant's financial capability or the effectiveness of the guarantee clauses contained in the private document.

Frequent mistakes

• Believing that signature verification turns a paper into a public deed: Signature verification attests to the signature, whereas a public deed is drafted entirely by the notary.
• Signing the document at home for verification by authenticity: If the act requires the authenticity modality, the signature must strictly take place before the notary clerk.
• Presenting damaged or outdated identity documents: Torn, re-laminated, or old-photo documents can prevent opening a signature file or performing in-person verification.
• Assuming the notary office guarantees contract payment: The notary office does not act as a guarantor or surety for the obligations assumed by the parties in a private instrument.

Legal basis

• Lei nº 8.935/1994, art. 1º — Establishes that notary and register services aim to guarantee publicity, authenticity, security, and effectiveness of legal acts Lei nº 8.935/1994, art. 1º.
• Lei nº 8.935/1994, art. 6º — Defines the authority of notary officers to recognize signatures and authenticate documents Lei nº 8.935/1994, art. 6º.
• Lei nº 10.406/2002, art. 104 — Establishes the validity requirements for legal transactions in national law Lei nº 10.406/2002 — Código Civil, art. 104.
• Lei nº 10.406/2002, art. 215 — Deals with the public faith attributed to public deeds and notarial acts Lei nº 10.406/2002 — Código Civil, art. 215.

Frequently asked questions

What is the difference between signature verification by resemblance and by authenticity?

In verification by resemblance, the notary office compares the document signature with the signature card stored on file. In verification by authenticity, the signatory appears in person at the notary office, signs the paper before the clerk, and signs the terms ledger.

Does signature verification certify the validity of the document's content?

No. Signature verification certifies exclusively the authorship of the signature or the presence of the signatory during the act. It does not validate the content of contractual clauses, the legality of the transaction, or the financial capacity of the parties.

What is the liability of the civil-law notary office in signature verification?

Notarial liability is limited to verifying the signature or formally identifying the signatory during the in-person act. The notary is not liable for the financial execution or performance of the obligations agreed upon in the private instrument.

How does the procedure for signature verification by authenticity work?

The individual comes to the notary office with an original ID document and the unsigned contract. They sign the document in the presence of the clerk, fill out the authenticity terms ledger, and receive notarial validation.

What documents are required to perform signature verification?

It is necessary to present an official photo ID document and CPF. For the resemblance modality, only the signed document and a signature card previously opened at the notary office are required.

Editorial footer

Editorial Team: Tabelionato de Notas do Recife (5th Notary Office of Recife)

Date of last legal review: August 25, 2026

Regulatory version: In compliance with Lei nº 8.935/1994, Código Civil (Civil Code), and CNJ Provisions.

Informational content; does not replace legal advice for specific cases.

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