Can I authenticate someone else's document?

Yes, as a rule, You can authenticate someone else's document.For a copy to be authenticated, simply present the original document and a legible copy to the notary's office. The owner does not need to be present, have a signature on file, or issue a power of attorney, as the notary only certifies that the copy corresponds to the original presented. The requirements are different when the requested service is signature verification or another personal act.

Summary

• Is it possible to authenticate a document belonging to another person?
• What to take to the notary's office to authenticate a copy.
• When a power of attorney or the presence of the account holder is required.
• Difference between copy authentication and signature verification.
• How digital document authentication works.
• When can public bodies verify a copy without a notary?

Quick facts

1. Purpose of authentication: The notary compares the copy with the original document and declares that the reproduction is accurate. This procedure does not confirm that the information in the original is true.
2. Absent holder: The authentication of a copy does not, as a rule, require the document owner to be present, since the purpose of the act is to ensure the accuracy of the reproduction presented.
3. Public bodies: In dealings with public administration, Law No. 13.726/2018 waives the requirement for notarization of copies and allows the administrative agent to verify them against the original.

What does it mean to authenticate a copy of a document?

Authenticate a Valid identity document It's more than a simple bureaucratic act. It's a legal mechanism that grants reliability to documents used in formal negotiations, legal disputes, or administrative proceedings. In the business world, for example, this practice prevents challenges to the veracity of the information provided, protects against fraud, and ensures smoother document processing. 

With the advancement of digitalization, the concept began to encompass not only the equivalence between a copy and a physical original, but also the verification of identity and integrity in electronic files, through digital signature tools.

Therefore, document authentication is the procedure by which an agent with public trust (such as a notary or clerk) certifies that the copy presented is faithful to the original document. In the case of digital authentication, this equivalence is verified through electronic mechanisms, such as digital certificates and cryptographic hashes.

This process grants legal validity to the copy, which then has the same value as the original document at the time of authentication, as long as it remains unchanged. It's a way to mitigate fraud, streamline administrative procedures, and ensure legal certainty.

Service	What the registry office verifies	Does the policyholder need to be present?
Copy authentication	If the copy matches the original presented.	As a rule, no.
Recognition of signature by similarity	If the signature matches the filed record	As a rule, no.
Authenticity signature recognition	Identity and authorship of the signature	Yes, in person or via video conference.
Digital authentication	Correspondence and authenticity of the electronic document	It depends on the electronic procedure.
Issuance of a certificate or performance of a personal act.	Specific requirements of the requested service.	It may be necessary

Can I authenticate someone else's document?

This practice is authorized when the third party responsible for authentication can prove their power of attorney, which is usually done through a notarized power of attorney. There are also cases where simply verifying the signature previously registered with the notary is sufficient. 

Companies with recurring processes can delegate this activity to specific employees, as long as they have the necessary documentation. Another possibility includes digital authorization, enabled by systems such as signature with digital certificate, which gives legitimacy to the delegation of formal acts without the need for physical presence.

In some contexts, it is possible to authenticate documents that do not belong to the applicant. However, this depends on specific legal conditions. The two main requirements for authenticating third-party documents are:

• notarized signature: if the document holder has a registered signature (open signature) at the notary's office where the procedure will be carried out, it is possible to authenticate the copy based on checking the original;
• valid power of attorney: in more formal situations, such as legal representation by relatives or attorneys, it is necessary to present a power of attorney with specific powers for this purpose.

Without one of these conditions, the registry office is not authorized to perform the procedure. Lack of authorization may constitute a legal violation, as we will see below.

When can a notary office refuse to authenticate a document?

Authenticating documents without proper authorization poses risks not only to the applicant but also to the institution performing the act. If the notary's office performs the authentication without the legally required care, it may be held liable for complicity or negligence. Penalties may include personal liability for the clerk or notary, as well as administrative and civil proceedings. 

In the business context, irregular practices can jeopardize commercial agreements, lead to contract cancellation, and result in litigation. In this sense, the use of reliable electronic signatures It is a measure that prevents irregularities and promotes greater traceability of authorizations.

Notarizing documents on someone else's behalf without formal permission can result in serious legal consequences. This act can be classified as:

• ideological falsehood (art. 299 of the Penal Code), if there is a distortion of the truth in the elements of the document;
• forgery of private document (art. 298 of the Penal Code), in cases of fraudulent alterations or reproductions.

In addition to criminal implications, there is also civil liability for damages caused to third parties. Therefore, the representation must be properly formalized.

What does the legislation say about authentication?

Beyond the Law No. 13.726 / 2018 and the Provisional Measure No. 2.200-2/2001, there are complementary devices that guide the operation of notary offices and the validity of digital documents. Law No. 8.935 / 1994 defines the powers of notaries and registrars and is often used as an interpretative basis in dispute cases. 

Recently, public bodies have also been adopting digital systems based on digital signatures with legal validity, which sets a precedent for private companies to adopt equivalent models. The legislation, therefore, not only regulates but also encourages the replacement of manual processes with secure and auditable digital means.

A Law No. 13.726 / 2018, known as the Debureaucratization Law, waives the need for authentication of documents in relations with public bodies, as long as the original is presented. Provisional Measure No. 2.200-2/2001 regulates the legal validity of electronic signature using digital certificates, expanding the possibilities of document validation without the need for notarial authentication.

Authentication is still required in many private relationships and commercial transactions, such as:

• purchase and sale of real estate;
• opening of companies;
• presentation of diplomas and certificates;
• bidding processes;
• validation of contracts in sensitive negotiations.

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Documents that can and cannot be authenticated

Documents subject to authentication also include certificates issued by government agencies, technical reports, employment contracts, and contractual amendments. Prohibited documents are those whose origin cannot be proven or whose content presents inconsistencies, such as digitally signed documents by image, without valid certification. 

Therefore, ideally, documents should be printed from trusted platforms, with security features such as hashing, timestamping, or QR codes that prove the origin and integrity of the information.

Some documents can be authenticated as long as they are presented in accordance with legal requirements. The most common include:

• personal documents (RG, CPF, certificates);
• diplomas and academic transcripts;
• articles of association and powers of attorney;
• negative certificates and balance sheets;
• transaction vouchers and receipts.

On the other hand, there are documents that cannot be authenticated, such as:

• non-printed digital files;
• copies of certified copies;
• scratched or damaged documents;
• blank papers or papers with empty spaces;
• records with offenses or false information;
• documents without an original signature or with the signature of a person without legal powers.

Difference between physical and digital authentication

Physical authentication requires going to the notary's office, queuing and paying per page, while digital authentication can be done remotely, with authentication by facial biometrics or digital certificate. This method has become popular among companies that need to handle contracts on a large scale, such as legal departments and sales teams. 

With digital platforms for signing documents, process control is centralized, with the possibility of automatic log generation and integration with other systems. Furthermore, digital authentication promotes sustainability by reducing paper use and physical travel.

Does an electronic signature replace authentication?

In practical terms, replacement occurs whenever the document does not necessarily require a notary seal. To do this, it is important to ensure that the electronic signature used is in compliance with legal standards. There are even situations in which qualified digital signatures are preferred by public bodies, such as when submitting petitions to the Judiciary or validating certificates. 

This trend points to a change in documentary culture, where technical reliability takes precedence over physical certification, especially when using a signer compatible with the ICP-Brasil standard.

Companies that use digital signature platforms can:

• reduce notary and logistics costs;
• increase productivity in document management;
• mitigate risks of loss or fraud;
• improve the customer and internal team experience.

It is worth remembering that electronic signature can be simple, advanced or qualified, according to the level of security required by the document.

When to use digital authentication or electronic signature?

The choice between one or the other should consider the recipient's level of demand, the type of document, and the volume of signatures. For sales processes, for example, electronic signature on contracts speeds up lead conversion, while digital authentication can be recommended when the document needs to be presented to third parties who require notarized proof. 

With the increased use of smart contracts and integrated systems, companies are increasingly automating these definitions based on internal compliance and document security policies. For routine documents, such as service contracts, declarations, authorizations, and acceptance terms, free digital signature is enough.

In high-value transactions, such as real estate and corporate contracts, it is recommended to use signature with digital certificate. If the company does not yet have the internal infrastructure for this, it can hire digital platforms with tailor-made plans.

What should I take to the notary's office to authenticate a third-party document?

In addition to the documents already mentioned, it is important to present proof of employment if the authentication is linked to professional activities, such as commercial representation contracts or corporate documents. 

Companies can facilitate the process by using stamps, certified copies of powers of attorney, and digitally signed statements. Another alternative is to use a digital signature platform with certification, which reduces the need for in-person authentication and formalizes the delegation of powers in advance, making the process more agile and secure.

If physical authentication is the option, the documents generally required are:

• original document to be authenticated;
• legible copy without erasures;
• identity document of the person requesting it;
• power of attorney (if applicable);
• confirmation of the open signature of the document holder at the notary's office.

It is recommended that you contact the registry office in advance to check specific requirements and updated values.

So, can I authenticate someone else's document?

Yes, as a rule, It is possible to authenticate someone else's document. Without a power of attorney and without the holder having a signature registered at the notary's office. The interested party must present the original document and a legible copy so that the notary can verify that both versions have the same content. The holder's presence may be required for other services, such as signature authentication, but not for the simple authentication of a copy.

The good news is that, with the evolution of electronic systems, it is increasingly viable to replace this type of procedure with electronic signature with legal validity, which makes the process safer, faster and more efficient for legal and operational teams.

However, there are caveats. Permission to authenticate another person's document is subject to the existence of a notarized signature or formal power of attorney. Outside these conditions, the procedure is irregular and may result in legal penalties. On the other hand, electronic signature emerges as a valid and secure alternative for many of the demands of everyday business. By adopting solutions like ZapSign, you gain agility, reduce costs, and increase the return on investment in document processes.

By the way, take advantage of the fact that you have reached the end of this content and Click here to see how ZapSign's electronic signature can help you!