E-Signature Security: Encryption, Compliance, and Trust Explained

Why E-Signature Security Matters

When you send a document for signature, you're entrusting sensitive information to a third-party platform — business terms, financial details, personal data, and legal commitments. Understanding how that platform protects your data isn't optional. It's essential.

The Security Stack: How SignFlow Protects Your Documents

1. Encryption in Transit (TLS 1.3)

Every document, every API call, every page load is encrypted using TLS 1.3 — the latest transport layer security protocol. This prevents anyone from intercepting data as it moves between your browser and our servers.

2. Encryption at Rest (AES-256)

Once your documents reach our servers, they're encrypted using AES-256 — the same standard used by banks and government agencies. Even if someone gained physical access to our storage, they couldn't read your files.

3. Tamper-Evident Seals

After signing, each document receives a cryptographic hash (SHA-256) that acts as a digital fingerprint. If even a single character is changed after signing, the hash won't match — providing proof of tampering.

4. Digital Certificates

Every completed document includes a Certificate of Completion with:

• All signer identities and actions
• Timestamps for every event
• IP addresses and device information
• Document hash for integrity verification

Authentication: Verifying Signer Identity

Email Verification

The most common method — signers receive a unique, time-limited link to their verified email address.

SMS/Phone Verification

An additional code sent via text message adds a second factor of identity verification.

Knowledge-Based Authentication (KBA)

Questions generated from public records that only the true signer can answer.

ID Verification

For high-value documents, signers can be asked to photograph their government-issued ID for comparison.

Access Codes

You set a code that the signer must enter — useful when you've verified their identity through another channel.

Compliance Frameworks

SOC 2 Type II

SignFlow is SOC 2 Type II certified, meaning an independent auditor has verified our security controls over an extended period. This covers:

• Security (protecting against unauthorized access)
• Availability (system uptime and reliability)
• Confidentiality (protecting sensitive information)

GDPR

Full compliance with EU data protection requirements, including data minimization, purpose limitation, and right to erasure.

HIPAA

Business Associate Agreements available for healthcare organizations that need to sign documents containing protected health information.

eIDAS

Compliant with EU electronic signature regulations at all three levels (SES, AES, QES).

Infrastructure Security

• Multi-region hosting — documents stored across geographically distributed data centers
• Automatic backups — continuous backup with point-in-time recovery
• DDoS protection — enterprise-grade protection against denial-of-service attacks
• Vulnerability scanning — continuous automated security testing
• Penetration testing — regular third-party security assessments

Best Practices for Users

1. 1Enable two-factor authentication on your SignFlow account
2. 2Use strong, unique passwords — preferably with a password manager
3. 3Review access regularly — remove team members who no longer need access
4. 4Use appropriate authentication — match verification level to document sensitivity
5. 5Verify recipients — double-check email addresses before sending sensitive documents

Questions to Ask Any E-Signature Provider

• What encryption standards do you use at rest and in transit?
• Are you SOC 2 certified? Which type?
• How do you handle data residency and regional requirements?
• What happens to my data if I cancel my account?
• How often do you conduct penetration testing?

Trust Through Transparency

Security isn't just about technology — it's about transparency and accountability. SignFlow publishes our security practices, maintains certifications, and undergoes regular independent audits because trust is earned, not assumed.

Explore SignFlow's security features →