What Is a Qualified Electronic Seal (QSeal)?

QSeal in one paragraph

A Qualified Electronic Seal (QSeal) is an electronic seal created with a qualified seal certificate issued by an accredited Trust Service Provider (QTSP). Under eIDAS Article 36, data sealed with a QSeal enjoys the presumption of integrity and origin — meaning EU courts presume the data came from the sealing organisation and has not been tampered with. It is the organisational equivalent of a Qualified Electronic Signature (QES).

Art. 36

eIDAS legal presumption of integrity and origin

QTSP

Must be issued by an accredited provider

QSCD

Must use a qualified seal creation device

HSM

Private key stored in hardware security module

What makes a seal qualified?

A QSeal must meet all the requirements of an advanced electronic seal plus the qualified certificate and QSCD requirements.

The seal certificate is issued to a specific legal entity after identity verification by the QTSP. The certificate's subject field contains the organisation's verified legal name and registration details.

The private key is stored in a Qualified Seal Creation Device (QSCD) — typically a certified HSM. Only the organisation's authorised systems can invoke the seal. The key cannot be extracted or duplicated.

Any change to the sealed data after sealing is detectable through cryptographic hash verification. The seal includes a timestamp and the certificate chain needed for validation.

The certificate must be issued by a QTSP accredited under eIDAS by a national supervisory body. The QTSP verifies the organisation's legal existence and identity before issuing the seal certificate.

Where QSeal is used today

QSeal is increasingly required for regulatory compliance and automated signing.

EU Digital Product Passport (DPP)

Under the ESPR, DPP data must be signed or sealed by the data holder using a qualified electronic signature or seal. Manufacturers use QSeal to attest product data submitted to the EU DPP registry.

Electronic Certificate of Conformity (eCoC)

Manufacturers seal conformity certificates with QSeal to prove the data originated from their organisation. Market surveillance authorities can verify the seal independently.

Batch signing for production lines

Manufacturing systems apply QSeal automatically via API for each production batch. Typical throughput: thousands of seals per day with sub-second latency per seal.

Official documents and certificates

Universities seal diplomas, governments seal official records, and companies seal annual reports. The seal proves organisational origin without requiring an individual to sign each document.

QSeal implementation data: providers, costs, and API performance

Specific data for organisations evaluating QSeal infrastructure.

EU QTSPs offering QSeal

As of 2026, 78 QTSPs appear on the EU Trusted List with QSeal certification. Major providers include DocuSign EU (Belgium), Namirial (Italy), Signaturgruppen (Denmark), itsme (Belgium), and Certigna (France). eSign.AI partners with 5 EU QTSPs to provide QSeal via API across all member states.

QSeal API performance

QSeal application via REST API: 800-2000 ms per seal (including HSM round-trip). Batch sealing optimisation: 5-10 seals per second sustained throughput. For DPP compliance at manufacturing scale (10,000+ products/day), this requires 2-3 HSM instances in load-balanced configuration.

QSeal vs QES cost comparison

QSeal is typically priced per seal: $0.05-0.20 at volume, $0.50-1.00 at low volume. QES is priced per signature: $1.50-5.00. For machine-to-machine signing (product data, certificates, regulatory filings), QSeal is 10-20x cheaper than QES per transaction.

QSeal in practice: EU eCoC, DPP, and batch compliance signing

Real-world applications where QSeal provides value beyond human signatures.

EU eCoC (electronic Certificate of Conformity)

Since June 2026, eSign.AI supports XML file upload with e-seal signing for automotive manufacturers meeting EU eCoC compliance requirements. This allows manufacturers to seal vehicle compliance data at production scale — thousands of certificates per day — without human sign-off on each document. The eCoC use case demonstrates QSeal's core advantage: machine-speed signing with legal entity attribution.

Digital Product Passport (DPP)

The EU DPP regulation requires manufacturers to attach verified product data to goods sold in the EU market. QSeal ensures this data is authentic and tamper-evident. eSign.AI's DPP signing capability (in development) will allow manufacturers to seal product passport data via API, integrating with PLM and ERP systems.

Batch regulatory filings

Government agencies increasingly accept electronic seals for regulatory submissions: tax filings, customs declarations, statistical reports, and compliance certificates. QSeal provides the legal entity guarantee that a human signature cannot — it proves the organisation approved the filing, not just an individual employee. This is particularly valuable for filings signed under delegation or automated workflows.

Common questions

QES is applied by a natural person (individual) and expresses personal intent to sign. QSeal is applied by a legal entity (organisation) and attests to the origin and integrity of data. Both use qualified certificates from a QTSP.

How eSign.AI applies this in practice

eSign.AI supports machine-to-machine sealing workflows through the applicable trust-service and certificate-provider path. Confirm the qualified trust service provider, certificate holder, legal effect, and production configuration for each jurisdiction and use case.

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Explore the right eSignature approach for your business

Talk to our team about eSignature requirements, compliance considerations, and document workflows across your target markets.

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