Digital Signature

Certificate-backed digital signatures for high-trust agreements

Use CA-issued certificates, identity verification, and tamper-evident audit trails to protect high-value agreements and support AES/QES workflows under eIDAS.

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Digital signature certificate validating a signed agreement

What is a digital signature?

A digital signature is a certificate-backed form of electronic signature that uses cryptographic keys to link a signer to a document and detect later changes. Under eIDAS, digital-signature workflows can support stronger assurance levels such as advanced electronic signatures (AES) and qualified electronic signatures (QES), depending on identity proofing, certificates, and trust-service setup.

Why use digital signatures for critical agreements

Add stronger identity, integrity, and evidence without slowing trusted signers.

Certificate details linked to signer identity

Verify signer identity with certificates

Bind signatures to certificate-backed identity data so reviewers can see who signed and how trust was established.

Tamper detection for a digitally signed document

Detect document changes after signing

Use cryptographic integrity checks to show whether an agreement was altered after the signature was applied.

Signature assurance levels from standard to qualified

Match assurance to document risk

Apply everyday e-signing, AES, or QES paths based on transaction value, jurisdiction, and compliance needs.

Signing policy recommending the right assurance level

Choose the right assurance level

Use standard e-signing for everyday approvals, AES workflows when stronger signer identification and integrity evidence are needed, and QES paths for the highest-assurance EU transactions under eIDAS.

Signer identity verification before digital signing

Verify the signer before signing

Add identity checks through Nota Sign Identify, including OTP, access codes, ID verification, or regional digital IDs where available. Stronger identity evidence helps reduce fraud and supports non-repudiation.

CA certificate applied to a digital signature

Apply a CA-issued certificate-backed signature

Use CA-issued certificates and cryptographic signing data to connect the signer, certificate, and document. The signed file can then be validated for authenticity, certificate trust, and later tampering.

Audit trail for a high-trust signed agreement

Preserve audit-ready evidence

Keep signing events, identity checks, timestamps, IP data, certificate evidence, and document status changes in a complete audit trail so legal, compliance, and IT teams can review what happened.

Digital signature workflow connected to business systems

Built for global signing operations

Use digital-signature workflows alongside templates, routing, identity checks, integrations, and APIs. Teams can standardize stronger signing paths for regulated agreements while keeping everyday documents fast and familiar.

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Digital Signature FAQs

Answers about certificate-backed signing, AES, QES, eIDAS, and audit evidence.

Sign critical agreements with stronger evidence

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