Features
Evidence features most e-sign tools don't even try to provide
Not just evidence — a complete signing platform with every workflow feature businesses need.
Evidence Core
Certificate of Completion
Every signed PDF includes a professional certificate with signer details, IP addresses, timestamps, document hash, and audit summary.
Cryptographic Proof
Visual hash chain diagram embedded in every document. See exactly how each event links to the next — any post-sealing modification breaks the verification chain and can be detected.
PAdES-LTA Digital Signatures
Every sealed PDF carries a PAdES-LTA (Long-Term Archival) digital signature with embedded Document Security Store and Document Timestamp. AATL-certified (Adobe Approved Trust List) and HSM-backed — open in Adobe Acrobat and see a green checkmark confirming "Signed by Abundera, Inc." No manual certificate installation needed. Designed for long-term validation with embedded OCSP responses and archival verification material.
Dual RFC 3161 Timestamps
Two independent Timestamp Authorities (SSL.com + Sectigo) each cryptographically attest to the exact time and content of sealing. Redundant proof — even if one TSA is compromised, the other stands.
Client-Side Hash Signing
Every signer's browser independently computes a SHA-256 hash of the document and signs it with an ephemeral ECDSA key before submission. The hash is shown to the signer so they can independently verify the document was never altered. No other e-signature platform offers client-side cryptographic proof.
Personal Document Seal PATENT PENDING
Every signer gets a unique verification code tied to the exact document content. Add it to Google Authenticator or any authenticator app — and verify your document hasn't changed, anytime, anywhere, even offline. The code is generated from a digital fingerprint of every word, every field, and every signature. No other e-signature platform offers this.
Plain-English Summary
Signers can request an automatically generated plain-English description of the document. Key obligations, deadlines, and financial terms — explained clearly before they sign.
See all 20 languages →Identity & Access
SMS OTP Verification (Professional+)
Optional phone verification via one-time passcode before signing. Adds access assurance — not government identity proof — with Twilio-powered SMS delivery. 6-digit code, 10-minute expiry.
Document-Bound OTP PATENT PENDING
Unlike every competitor's random OTP, our verification code is cryptographically derived from the document content. Successful verification simultaneously proves signer identity AND document integrity in one atomic step. If the document is tampered with after the code is sent, verification fails — even if the code is correct. Blocks MitM proxy attacks.
Client-Side Hash Signing PATENT PENDING
Your browser independently computes a SHA-256 hash of the document and signs it with an ephemeral ECDSA P-256 key. The private key never leaves your browser. This provides server-independent proof that you saw and agreed to the exact document content — not just that the server says you did.
Access Code Protection
PIN-protect sensitive documents. Sender sets a code, shares it out-of-band. Document won't load until the correct code is entered. SHA-256 hashed, never stored in plain text.
331 Legal Templates
Ready-to-use, legally reviewed templates across 30+ categories — NDAs, leases, employment, healthcare, finance, and more. All with Markdown field placeholders.
Workflow & API
Signing Order & Bulk Send
Enforce sequential signing — signer B can't sign until signer A completes. Bulk send up to 100 envelopes in a single API call with per-recipient field merging.
Webhooks & Callbacks
HMAC-signed webhook notifications on every event: completed, signed, declined, voided, expired, delegated. Integrate signing into any workflow.
Auto Reminders
Configurable automatic reminders for unsigned signers. Set frequency (1-30 days) and max count (up to 10). Cron-powered, fully hands-off.
Decline with Reason
Signers can formally decline with a required reason. Sender gets notified instantly via email. Full audit trail of the decision.
Public Verification
QR code on every document links to a public verification page. Anyone can confirm authenticity, signer identities, and chain integrity without an account. Upload a PDF to verify its hash.
Geo-Lock & VPN Blocking (Professional+/Business)
Restrict signing by country using Cloudflare geo-detection. Block VPN and proxy connections with ASN-based detection. Bot and email prefetch traffic automatically flagged in the audit trail.
Signing Links (Professional+)
Create reusable signing links that anyone can use to sign a document. Share a single URL — each visitor gets their own envelope. Ideal for onboarding, waivers, and self-service agreements.
Signer Delegation
Signers can delegate signing authority to someone else directly from the signing page. Chain limit enforced, full audit trail of the delegation, and the original signer is marked as delegated.
Embedded Signing
Embed the signing experience directly in your app via iframe. Keep users in your product — no redirects, no new tabs. Full API control with postMessage events for completion callbacks.
SDK docs & code examples →In-Person Signing
Kiosk mode for face-to-face signing on a shared device. Hand the device to each signer in turn — each sees only their fields. Ideal for offices, notaries, and point-of-sale scenarios.
Remote Online Notarization (Business)
Legally binding video notarization powered by BlueNotary. Connect signers with a commissioned notary in real-time for documents that require notarial acts. Session recorded, notarized PDF returned, and full audit trail preserved in the evidence package.
Passkey Biometric Verification (Professional+)
WebAuthn device biometric proof using fingerprint, face recognition, or hardware security keys. Adds cryptographic device-bound identity verification to the signing ceremony — stronger than passwords, phishing-resistant, and logged in the evidence package.
Team & Governance
Developer Portal
Full management dashboard — envelopes, templates, API keys, webhooks, branding, and usage stats. SSO via Abundera account. No separate login required.
Signing Ceremony Proof
Records every interaction during signing — page views, field focus, consent checks, signature actions. Tracks exact viewing duration, scroll depth, and device details. All captured in the evidence package.
Signer Evidence Score
Weighted multi-factor evidence score for each signer based on email verification, ESIGN consent, SMS OTP, VPN status, viewing duration, scroll depth, identity photo, and browser GPS. Rated Basic to Maximum on the certificate.
Court-Ready Declaration (Professional+)
Auto-generated 13-section "Declaration of Custodian of Records" PDF citing FRE 803(6), 901(b)(9), 902(11), 902(14), and 28 U.S.C. § 1746. Includes a 26-term technical glossary for the Court, PAdES-LTA digital signature, and eight verification layers. Formatted to support use in litigation and evidentiary review, subject to counsel and local rules.
Identity Photo Capture (Professional+)
Request or require a webcam photo of each signer during signing. Records camera availability, permission state, and capture events. Photo stored in the evidence package — never shared publicly. Use only where justified by document risk, privacy obligations, and consent requirements.
Browser GPS Location (Professional+)
Request or require precise GPS coordinates from the signer's browser. Records latitude, longitude, accuracy radius, and permission state. Shown on the Certificate of Completion and verification page. Availability depends on browser/device permissions and should be used only where location evidence is relevant and lawful.
Audio & Video Statements (Professional+)
Request or require signers to record themselves reading a sworn statement aloud. Audio captures voice biometrics; video adds facial identification. Recordings stored in the tamper-evident evidence package with SHA-256 hashes. Provides richer evidence than a standard click-to-sign flow, when appropriate for the transaction. Use only with clear disclosure, informed consent, and retention policies appropriate to the transaction.
Team Organizations (Business)
Create shared workspaces where your team collaborates on envelopes and templates. Role-based access (owner, admin, member, viewer), email invitations, and a dedicated org audit trail. No per-seat fees — each extra user adds bonus envelopes to your plan.
Custom Email Domains (Business)
Send signing requests from your own domain — notifications@yourdomain.com instead of a generic sender. Builds trust with recipients, improves deliverability, and reinforces your brand on every email touchpoint. DNS verification with guided setup.
State-Specific ESIGN Consent
Go beyond generic federal consent. Set jurisdiction per envelope to add state-specific legal disclosures for New York, California, Texas, Illinois, and Washington. Document type exclusion warnings flag contracts that may not be valid under state law. Full consent text — federal plus state supplemental — stored in the evidence package.
Security & Compliance
Enterprise-grade by default
What these records help prove
- ✓ Document integrity after sealing
- ✓ Time of sealing
- ✓ Signer access and signing interaction
- ✓ Configuration and delivery history
- ✓ Optional additional identity-strength signals
What these records do not prove by themselves
- — Subjective understanding
- — Legal capacity
- — Absence of coercion
- — Ultimate admissibility outcome
- — Success in litigation
Enterprise Ready
Built for buyer review, not just signer clicks
Ready to get started?
See our plans or try the full signing experience right now — no account needed.