Verify Authenticity of Signed Document: International Trade

International trade generates millions of contracts, letters of credit, bills of lading and certificates of origin signed electronically each year across dozens of different jurisdictions. Yet a study by the ICC (International Chamber of Commerce) published in 2024 reveals that 34% of cross-border commercial disputes involve disputes relating to the authenticity or integrity of signed documents. Faced with this challenge, knowing how to verify the authenticity of a signed document in the international trade sector has become a strategic skill for legal, financial and logistics departments. This article guides you through the technical mechanisms, international standards and operational best practices to adopt in 2026.

Understanding the Authentication Mechanisms of Electronic Signatures

Before verifying the authenticity of a signed document, it is essential to understand what constitutes this authenticity from a technical perspective. A qualified electronic signature relies on three fundamental pillars: public key cryptography (PKI), digital certificates and qualified time stamps.

Asymmetric Cryptography: The Foundation of Verification

When a signatory affixes their electronic signature, a cryptographic algorithm generates a unique fingerprint (hash) of the document. This fingerprint is encrypted with the signatory's private key, thus creating the digital signature. To verify the authenticity of a signed document in international trade, the verifier uses the corresponding public key to decrypt this fingerprint and compare it to the recalculated hash of the document received. If the two match, two certainties are established: the document has not been modified since signing (integrity), and only the holder of the private key could have signed (authenticity).

The most widely used algorithms in 2026 remain RSA-2048, ECDSA and, for environments anticipating post-quantum cryptography, CRYSTALS-Dilithium, now standardised by NIST.

Digital Certificates: The Chain of Trust

The public key alone is insufficient. Its reliability depends on the digital certificate that accompanies it, issued by a Certification Authority (CA) recognised. In the European context governed by the eIDAS regulation, only qualified trust service providers (QTSP) listed on the national trust lists (Trusted Lists published on the official EU portal) can issue qualified certificates.

For international trade, the complexity lies in mutual recognition between jurisdictions. A certificate issued by a US-based CA (example: DigiCert or Sectigo) may not benefit from the reliability presumption granted to qualified eIDAS certificates in Europe. Conversely, a qualified eIDAS certificate is not automatically recognised as qualified in Japan or China, even though it will generally be accepted as legal evidence.

Qualified Time Stamp: Proof of Anteriority

The qualified time stamp (QTS) constitutes the third pillar. It certifies, in an enforceable manner, that the document existed in its signed form at a precise moment. In international business transactions, this proof of anteriority is crucial for resolving disputes related to contractual deadlines, guarantee effective dates or delivery deadlines. The ETSI EN 319 421 standard governs the policies and procedures applicable to qualified time-stamping authorities in the eIDAS area.

Practical Methods of Verification in International Trade

Cryptographic theory must translate into concrete operational procedures. Here are the proven methods for verifying the authenticity of a signed document in the international trade sector.

Verification via Certified Signature Platforms

The most direct method is to use the original signature platform or a recognised third-party verification tool. Most eIDAS-compliant electronic signature SaaS solutions incorporate a public verification portal or a verification API. Certyneo, for example, generates for each signed document a proof report (Audit Trail) downloadable in PDF/A, including the cryptographic fingerprint, verified signatory identity, qualified time stamp and connection metadata.

For documents in PDF format, the Adobe Acrobat Reader (version 11 and higher) allows native verification of PDF/A signatures compliant with the PAdES standard (ETSI EN 319 132). It displays a validation banner indicating whether the signature is valid, whether the certificate is still valid and whether the document has been modified after signing.

Verification through Institutional Tools

The European Commission provides DSS (Digital Signature Services), a reference open source tool for validating signatures in PAdES, XAdES, CAdES and ASiC formats. Available online on the portal ec.europa.eu/cefdigital/DSS, it automatically verifies the signature against European Trusted Lists.

For documents from third countries, several national authorities offer similar tools:

• The Adobe Approved Trust List (AATL) portal for globally recognised certificates

• The Trust List Browser from ETSI for European QTSPs

• The verification tool of the International Chamber of Commerce (ICC) for standardised commercial documents (Incoterms, electronic letters of credit eLCs)

Verification of Scanned Paper Documents with Electronic Signature

In international trade, many hybrid documents coexist: paper originals bearing a scanned handwritten signature, with or without an electronic seal. In this case, verification requires a different approach:

1. Verification of the electronic seal (eSealing) affixed by the issuing body to the scanned PDF

1. Control of the QR code or 2D barcode integrated, referring to a secure register

1. Consultation of source registers (for certificates of origin, phytosanitary certificates, etc.) with the competent authorities (customs, chambers of commerce)

For electronic bills of lading (eBL), verification now often takes place through specialised platforms such as BOLERO, essDOCS or DCSA (Digital Container Shipping Association), which maintain registers of electronic property titles.

Challenges Specific to International Trade

Interoperability between Jurisdictions and Standards

The main challenge of verifying authenticity in international trade is the absence of a single worldwide standard. Three major frameworks coexist in 2026:

• Europe: eIDAS 2.0 Regulation (EU Regulation 2024/1183, applicable since May 2024), which extends mutual recognition and introduces the European Digital Identity Wallet (EUDIW)

• United States: ESIGN Act (2000) and UETA, with a technology-neutral approach but without a centralised trust list

• Asia-Pacific: APEC Framework (e-Commerce Steering Group), with very heterogeneous levels of maturity depending on member countries

The UNCITRAL (United Nations Commission on International Trade Law) published in 2017 the Model Law on Electronic Transferable Documents and Signatures (MLETR), subsequently adopted by Bahrain, Singapore, the United Kingdom, the UAE, Germany, France (Ordinance No. 2024-872) and a dozen other states. This law constitutes the foundation of a future worldwide standard for verifying electronic commercial documents.

The Problem of Languages and Formats

A contract signed in Mandarin by a company based in Shanghai, using a certificate issued by a CA certified by the MIIT (Chinese Ministry of Industry and Information Technology), presents specific challenges. Neither European tools nor Adobe will automatically integrate this CA into their trust lists. Verification then requires:

• The request for a certificate of legalisation (digital apostille if the country has joined the HCCH e-Apostille)

• Recourse to a bilateral trust third party or an international chamber of commerce

• The use of a neutral verification platform accepted by both parties in the contract

Managing the Risk of Certificate Revocation

A document may have been signed with a valid certificate at the time of signing, but this certificate may subsequently be revoked (compromise of the private key, change in signatory status, CA failure). Verification of authenticity must therefore include a check of the Certificate Revocation List (CRL) or an OCSP (Online Certificate Status Protocol) request at the time of verification.

The ETSI EN 319 102-1 standard requires that qualified signatures incorporate long-term validation evidence (LTV – Long Term Validation), enabling their validity to be verified even years after signing, regardless of the certificate's subsequent status. Consult our complete guide to eIDAS 2.0 regulation to further explore these long-term trust mechanisms.

Setting Up a Systematic Verification Procedure

Define an Internal Verification Policy

Faced with the complexity of verification in an international context, organisations must formalise an electronic signature verification policy (PEVS) integrated into their document management system. This policy must specify:

• The signature levels accepted depending on the nature of the document (SES, AES or QES according to eIDAS)

• The signature formats recognised (PAdES, XAdES, CAdES, JAdES)

• The lists of CAs accepted for each geographic partner area

• Procedures for manual verification of non-standard cases

• Retention periods for authenticity evidence

Automate Verification via APIs

For organisations handling large volumes of international documents, manual verification is untenable. Modern signature platforms, including Certyneo, expose REST verification APIs enabling the automation of authenticity control in document workflows (ERP, TMS, customs platforms). Such integration allows automatic verification of each document upon receipt, logging of the result and alerting in case of anomaly.

Certyneo's ROI calculator will allow you to estimate the productivity gains linked to automating these verifications in your organisation.

Train Operational Teams

Technology alone is not enough. Customs, procurement, legal and financial teams must be trained to recognise warning signs: absence of proof report, non-cryptographic image signature, expired certificate or issued by an unrecognised CA. Annual training, coupled with documented procedures, significantly reduces the risk of accepting a fraudulent document. Our glossary of electronic signatures is a useful educational resource for training your teams on fundamental concepts.

Legal Framework Applicable to Authenticity Verification in International Trade

The eIDAS Regulation and Its Evolution into eIDAS 2.0

In Europe, the legal foundation for verifying the authenticity of electronic signatures is the Regulation (EU) No. 910/2014 of the European Parliament and of the Council of 23 July 2014, known as the eIDAS regulation. Its article 25 sets out the fundamental principle: a qualified electronic signature (QES) has the legal effect of a handwritten signature and enjoys a presumption of reliability. Article 32 specifies the requirements for validating qualified electronic signatures, referring to ETSI technical standards.

Since May 2024, Regulation (EU) 2024/1183 (eIDAS 2.0) strengthens this framework by introducing the European Digital Identity Wallet (EUDIW), qualified electronic attribute attestations and enhanced governance of QTSPs. It also extends recognition of European qualified signatures to private sector entities.

French Law: Civil Code and Transposition

Under French law, articles 1366 and 1367 of the Civil Code (resulting from ordinance No. 2016-131) establish the probative value of electronic documents and electronic signatures. Article 1366 specifies that electronic documents have the same evidentiary force as documents on paper media, provided that the person from whom it emanates can be properly identified and the document is established and kept under conditions capable of guaranteeing its integrity. Article 1367 defines the electronic signature and refers to the conditions set out by decree (Decree No. 2017-1416 of 28 September 2017).

MLETR and International Law

At the international level, the UNCITRAL Model Law on Electronic Transferable Documents and Signatures (MLETR, 2017) is the reference for dematerialised commercial documents (bills of lading, bills of exchange, warehouse receipts). Its article 10 requires that any control system for transferable electronic documents is reliable and appropriate to the context. France transposed it via Ordinance No. 2024-872 of 27 September 2024.

GDPR and Retention of Evidence

Verification of authenticity often involves the processing of personal data (signatory identity, behavioural biometric data). Regulation (EU) 2016/679 (GDPR), in particular its articles 5 (principles relating to processing), 17 (right to erasure) and 89 (archiving), governs the duration and methods of retention of verification evidence. In practice, signature audit reports must be retained for the duration of the limitation period applicable to the document concerned — up to 10 years for business documents (article L.110-4 of the Commercial Code) — which can create tension with the data minimisation principle.

Liability for Defective Verification

Acceptance of a document whose signature has not been properly verified can engage the contractual and tort liability of the organisation. In the event of document fraud facilitated by failure to verify, articles 1240 and 1241 of the Civil Code may be invoked. Furthermore, the NIS2 Directive (EU) 2022/2555, transposed into French law by law No. 2024-659 of 22 July 2024, imposes on operators of critical importance and essential entities requirements for the security of information systems including verification of integrity of electronic exchanges.

Use Scenarios: Verification of Authenticity in International Trade

Scenario 1: A European Import-Export Company Handling Several Hundred Contracts Annually

A small European industrial business specialising in the import-export of electronic components manages approximately 350 supplier contracts per year, with counterparties located in South-East Asia, North America and the Middle East. Before implementing a systematic verification procedure, its procurement teams accepted electronically signed contracts without checking the validity of certificates or the presence of a qualified time stamp. Following a dispute with a Malaysian supplier challenging the date of an electronically signed purchase order, the company suffered damage estimated at several tens of thousands of euros.

By deploying an automated verification API integrated into its ERP and adopting a policy requiring signatures at a minimum AES level for contracts under €50,000 and QES for higher amounts, the SME reduced the processing time for documentary disputes by 90% and eliminated incidents of acceptance of expired certificates. Return on investment was achieved in less than 8 months.

Scenario 2: A Customs Freight Forwarder Managing Multicount Electronic Declarations

A customs freight forwarder operating for a clientele of approximately 80 active principals processes daily certificates of origin, packing lists and commercial invoices signed electronically from 15 different countries. The diversity of formats (PAdES for European documents, XML signatures for Asian documents, hybrid paper-digital documents for some African countries) made manual verification extremely time-consuming — approximately 45 minutes per complex file.

By integrating a signature platform compliant with eIDAS with a multi-format verification module, the freight forwarder reduced this time to less than 5 minutes per file through automated verification, a reduction of 89% in processing time. Customs compliance (simplified customs clearance OEA regime) was also strengthened, reducing customs holds by 40% over a comparable area.

Scenario 3: An International Law Firm Specialising in Cross-Border Contract Law

A law firm with around twenty partners specialising in Europe-Asia cross-border M&A transactions is regularly faced with the need to verify the authenticity of documents signed by parties established in countries that do not recognise the eIDAS framework. For due diligence, each signed document (NDA, term sheets, protocols of understanding) must be subject to documented verification before being filed.

The firm adopted a two-tier procedure: automated verification by platform for documents in standard digital format, and recourse to a recognised certifying body (bilateral chamber of commerce or electronic notary) for documents from countries without an eIDAS equivalent. This approach made it possible to produce more robust due diligence reports, reducing requests for clarification from buyers by 35% and shortening transaction closing times by an average of 12 business days. To learn more about tools dedicated to legal professionals, consult our page dedicated to electronic signature for law firms.

Conclusion

Verifying the authenticity of a signed document in the international trade sector is a requirement that is both technical, legal and organisational. Cryptographic mechanisms (PKI, digital certificates, qualified time stamps), regulatory frameworks (eIDAS 2.0, MLETR, Civil Code) and verification tools (DSS, validation APIs, audit trails) form a coherent ecosystem, provided it is approached holistically.

Organisations that automate and formalise their verification procedures drastically reduce their exposure to document fraud, accelerate their contract cycles and strengthen their regulatory compliance. Conversely, the absence of a procedure exposes them to considerable financial and reputational risks.

Certyneo supports you in implementing an infrastructure for signature and verification compliant with international trade requirements. Create your free account and discover how our platform simplifies verification of authenticity of your cross-border documents today.