ESIGN & UETA Compliant

eIDAS-Aligned

Hash-Chained Audits

Enterprise-Grade Signatures. Startup-Friendly Pricing.

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Assess Risk2-min Security Audit

See Your Savings

Stop paying for paper, printing, and manual delays. Calculate your savings.

Documents Signed Monthly

Annual SavingsBased on $2.50 avg. cost of paper, toner, and labor per 14-page document.

$28,200

projected annual savings by digitizing

Trees SavedCalculated at 14 pages per document and 10,000 pages per tree.

16.8trees / yr

Water ConservedCalculated at 10 liters of water used to produce 1 page of paper.

1.68Mliters / yr

500+

Integrated Teams

10M+

Hardened Documents

60%

Average Efficiency Gain

4.9/5

Peer Review Average

Forensic Resilience Protocol

Architected for
the "Worst Case".

We don't ask you to trust our policy. We ask you to verify our architecture. 18 critical failure vectors, neutralized by design.

Cryptographic Integrity

“What if someone downloads a signed PDF, edits it, and claims the agreement was different?”

The IUSign Protocol

SHA-256 PAdES Seal. Even a 1-bit alteration invalidates the embedded cryptographic signature, providing instant forensic proof of tampering.

Identity Governance

“What if someone creates a fake iusign document and sends it to my client?”

The IUSign Protocol

Organization Root CA. Every verified document is cryptographically bound to your tenant's specific identity, making unauthenticated clones impossible.

Security Engineering

“What if someone intercepts our webhook and replays it with modified data?”

The IUSign Protocol

HMAC-SHA256 Signed Idempotency. Every payload is signed with a rolling secret; replayed or modified packets are rejected by the gateway.

Fraud Prevention

“What if an admin tries to alter or delete audit logs to hide fraud?”

The IUSign Protocol

DB-Level Immutable Triggers. We use hardened Postgres triggers that physically prevent 'UPDATE' or 'DELETE' actions on audit records.

Legal Compliance

“What if we’re under litigation and need to preserve a document indefinitely?”

The IUSign Protocol

Indefinite Legal Hold. Suspends all auto-deletion policies and mandates permanent archival until the hold is manually revoked.

Data Sovereignty

“What if we want to keep documents stored but destroy the encryption key?”

The IUSign Protocol

KMS DEK Invalidation. We physically purge the unique Data Encryption Key (DEK) from the KMS, rendering the storage-at-rest mathematically void.

Recovery Protocol

“What if we accidentally delete a document—can we recover it?”

The IUSign Protocol

30-Day Forensic Soft-Lock. Deletion triggers a 'Tombstone' state, allowing recovery via 2FA verification before final cryptographic erasure.

Forensic Audit

“What if a regulator asks us to prove deletion?”

The IUSign Protocol

Verified Deletion Certificate. We issue a cryptographic tombstone signed by the KMS proving the key destruction event.

Access Control

“What if someone signs from a shared device—can it be misused later?”

The IUSign Protocol

Ephemeral Signing Tokens. Sessions are tied to a one-time cryptographic nonce that expires immediately upon document submission.

Temporal Accuracy

“What if somebody changes document’s timestamp—how do we prove real time?”

The IUSign Protocol

RFC 3161 Trusted Timestamping. Timestamps are sourced from an external TSA, independent of the server's local clock.

Compliance Logic

“What if a user invokes GDPR deletion but it's legally required?”

The IUSign Protocol

Regulatory Hold Reconciliation. Automatically prioritizes legal retention mandates over deletion requests to ensure compliance.

Tenant Isolation

“What if two competing clients use iusign—how do you ensure zero leakage?”

The IUSign Protocol

Row-Level Security (RLS). Hardened database policies ensure that Client A can never physically access Client B's data at the kernel level.

Key Management

“What if our team uses the wrong API key—can data be accessed across tenants?”

The IUSign Protocol

Strict UUID Key Binding. API keys are cryptographically locked to a single Tenant ID; cross-tenant calls trigger an immediate security alert.

Anti-Phishing

“What if someone creates a lookalike domain (sign.c0mpany.com) to phish users?”

The IUSign Protocol

Verified Sender Profiles. We enforce SPF/DKIM and DMARC hardening, ensuring invitations only originate from your verified corporate domain.

Infrastructure

“What if your system goes down during a critical signing period?”

The IUSign Protocol

Multi-Region Hot-Failover. Real-time data replication across three geographic zones ensures zero data loss and sub-second recovery.

Portability

“What if we want to leave iusign—can we export everything?”

The IUSign Protocol

Open-Standard Export. Export full forensic packages in machine-readable JSON with PAdES-LTV signatures. No vendor lock-in.

Leak Containment

“What if an API key is leaked—can someone misuse it silently?”

The IUSign Protocol

IP-Bound Whitelisting. API tokens can be restricted to specific IP ranges, rendering leaked keys useless outside your corporate network.

Bulk Ops

“What if we send to 1000s and some fail—can we retry only failed ones?”

The IUSign Protocol

Atomic Bulk Retries. Our task queue tracks every individual recipient state; 'Retry' only targets failed nodes, never duplicates successful ones.

Engineered to outperform.

Swipe to compare

Capability Framework	IUSign	Enterprise Market Leader	Suite-Based Provider
Bulk Send Pipeline Automate high-volume distribution. Send personalized signature requests to thousands of recipients simultaneously via CSV/API.	Built-in / Unlimited	No	Limited
Domain White-labeling Remove vendor branding. Use your own custom domain (e.g., sign.acme.com) for a seamless, trusted recipient experience.	Standard / Native	Enterprise Only	No
API Ecosystem Full REST access. 39+ endpoints, SDKs, and developer-first documentation for rapid, secure product integrations.	Developer-First / Full	Restricted / Tiered	Restricted
Envelope Surcharge Zero hidden fees. Unlike competitors, we don't charge per-document overages or tiered usage surcharges.	Non-existent	Usage-based Fees	Usage-based Fees
GCP KMS Key Control Total data sovereignty. Your document encryption keys are wrapped by a master key residing in your own GCP KMS instance.	Included / Native	Unavailable	Unavailable
Cryptographic Provenance Immutable event integrity. Every action is cryptographically chained using SHA-256 hashes for irrefutable audit trails.	SHA-256 Chaining	None	None
Audit Integrity Hardened verification. Database-level triggers prevent any post-event modification of logs, even by system administrators.	DB-Level Triggers	Policy-Based	Log-Only
Data Sovereignty Verifiable deletion. Crypto-shredding ensures that once a document is deleted, its keys are destroyed across all nodes.	Crypto-Shredding	Storage-Based	Manual Deletion
Memory Security Zero-persistence processing. Sensitive data exists only in volatile RAM and is physically overwritten after encryption.	Zero-Persistence	Persistent Temp	Disk-Based
Hybrid Execution Digital-to-Analog bridge. Native support for 'Print & Sign' workflows while maintaining a digital forensic audit record.	Native Print & Sign	Manual / Complex	Unsupported
Signature Standards Global interoperability. Supports PAdES Long-Term Validation (LTV) for signatures that remain valid for decades.	PAdES-LTV Native	Optional / Add-on	Proprietary
Webhook Reliability Secure async sync. HMAC-signed, idempotent webhooks ensure your backend stays in sync without duplicate events.	HMAC / Idempotent	Simple POST	None
Forensic Audit Export Defensible evidence. Export full transaction metadata in machine-readable JSON for independent third-party verification.	Self-Verifying JSON	Dashboard Only	PDF-Only
Account Governance Least-privilege access. Granular, identity-bound roles (Owner, Admin, User, Viewer) prevent unauthorized data access.	Identity-Bound Roles	Shared Permissions	Limited
Multi-Party Routing Complex workflow logic. Define sophisticated sequential or parallel signing orders for multi-stakeholder agreements.	Sequential / Native	Limited / Add-on	Standard

Assess Risk

Current Feature Matrix Verification: April 2026

Core Ecosystem

Full Stack. Zero Bloat.

Visual Document Preparation

Drag-and-drop signature, text, date, and checkbox fields directly onto your PDF. Upload PDF or DOCX — automatic conversion via LibreOffice.

Sequential Multi-Party Signing

Define signing order: Person 1 → Person 2 → Person 3. Each signer receives the document only when it's their turn.

Immutable Audit Trail

Database-level triggers physically prevent deletion or modification of audit logs. SHA-256 hash chain per event.

Change Request & Revision Workflow

Signers click anywhere on the PDF to place comment pins. You resolve, upload a revised document, and re-send — all version-tracked.

Full White-Label Capability

Custom logo, brand colors, organization name, custom email from address, custom domain with DNS verification. Per-tenant usage limits enforced.

Smart Email Delivery

Redis-backed queue with exponential backoff retry. 4 Jinja2 email templates with custom composer and variable substitution.

Stuck Document Detection

Automatically detects documents inactive for 7+ days. Status filters, manual reminders, and blocker identification.

Security-First API

Cryptographically verifiable actions, SHA-256 event chaining, and PAdES-LTV validation. Idempotent webhooks with HMAC signatures for high-trust integrations.

Secure by Architecture

Infrastructure-Level Trust

AES-256-GCM GCP KMS Envelopes

Your document is encrypted with a unique data encryption key (DEK) before it ever touches disk. The DEK itself is wrapped with a master key controlled in your GCP KMS instance.

Deploy Control Key

IUSIGN_KERNEL_X64

// GCP KMS ENVELOPE HANDSHAKE

STATUS: ENCRYPTED

MASTER: kms:global:ias:key/01

DEK_HASH: sha256:5e8...3a2

// ACCESS LOGGED VIA CLOUD AUDIT ✓

SHA-256 Hash Chain Integrity

Every signature event — envelope created, document viewed, signature applied — is cryptographically chained. If a single record is altered, the entire chain triggers a violation.

Validate Integrity

IUSIGN_KERNEL_X64

// CRYPTO-CHAIN VERIFICATION

EVENT: SIG_LOG_09

SIGNED_BY: MICHAEL ROBERTS

HASH: 0x82f0be...a12b

PREV: VIEW_LOG_08

DOCUMENT_RENDERED

HASH: 0x41e9d4...d94c

INTEGRITY: MATHEMATICALLY VERIFIED ✓

Ephemeral Zero-Persistence Flow

Raw document content exists only in temporary memory buffers during processing. We physically collect garbage (GC) and overwrite memory sectors after encryption.

Simulate Breach

IUSIGN_KERNEL_X64

// ZERO-PERSISTENCE STREAM

... allocating ephemeral_buffer [0x00FF23]

input_stream = io.BytesIO(encrypted_blob)

transformer.flatten(input_stream)

! EMERGENCY WIPEOUT INITIATED !

overwrite_sectors(0x00FF23, pattern=0x00, passes=3)

SOVEREIGNTY PRESERVED ✓

Immutable PDF Flattening

Signatures aren't just invisible overlays; they are physically burned into the document's structure at 300 DPI, creating a permanent, flattened forensic record.

Verify Provenance

IUSIGN_KERNEL_X64

IUSIGN ARCHITECTURE VERIFICATION

PROCESS_ID: 97588

status = service.verify("pdf-render")

Result: SUCCESS -- ENFORCED

Universal Evidence Package

Export a self-contained, court-ready JSON bundle containing all metadata, signer IP logs, intent capture, and the full hash chain provenance.

Download Bundle

IUSIGN_KERNEL_X64

IUSIGN ARCHITECTURE VERIFICATION

PROCESS_ID: 72217

status = service.verify("evidence-json")

Result: SUCCESS -- ENFORCED

HMAC-Signed Idempotent Pipelines

Webhooks aren't just POST requests. They are HMAC-signed for security and support idempotent retry logic to ensure your backend stays in perfect sync.

Test Endpoint

IUSIGN_KERNEL_X64

IUSIGN ARCHITECTURE VERIFICATION

PROCESS_ID: 82605

status = service.verify("webhook-flow")

Result: SUCCESS -- ENFORCED

Scale bulk sends without jobs failing.

Distributed task queue + surgical retry. Failed recipients auto-retry without resending completed ones. Idempotent webhooks guarantee no duplicates.

Verify System Integrity

Common Queries

Everything you need to know.

Is IUSign legally binding?

Yes. IUSign is fully compliant with the ESIGN Act and UETA in the US, and aligns with eIDAS standards in the EU. We capture intent to sign, mandatory consent, and provide an immutable SHA-256 audit trail for every transaction.

How does the 'Zero-Persistence' security work?

Unlike traditional platforms, IUSign processes sensitive document data in ephemeral memory. Once the PDF is flattened and encrypted, the raw data is physically overwritten in memory, ensuring your document content is never stored in an unencrypted state.

Can I use my own domain for signing?

Absolutely. Our Growth plan includes full white-labeling, allowing you to use your own domain (e.g., sign.yourcompany.com) with automated SSL, custom email branding, and localized signing experiences.

What is an Immutable Audit Trail?

Every event in the signing process is cryptographically hashed and chained to the previous event. This creates a forensic record that cannot be altered without detection, ensuring absolute cryptographic certainty in a court of law.

Does IUSign have a developer API?

Yes. We pride ourselves on being developer-first. We offer 39 documented REST endpoints, Python and Node.js SDKs, HMAC-signed webhooks, and a sub-15 minute integration time for most applications.

Take control of your
document logistics.

Self-hosted ephemeral security, immutable audit trails, and 100% data sovereignty starts here.

Start Free(No credit card required)

Enterprise-Grade Signatures. Startup-Friendly Pricing.

See Your Savings

Architected for the "Worst Case".

“What if someone downloads a signed PDF, edits it, and claims the agreement was different?”

“What if someone creates a fake iusign document and sends it to my client?”

“What if someone intercepts our webhook and replays it with modified data?”

“What if an admin tries to alter or delete audit logs to hide fraud?”

“What if we’re under litigation and need to preserve a document indefinitely?”

“What if we want to keep documents stored but destroy the encryption key?”

“What if we accidentally delete a document—can we recover it?”

“What if a regulator asks us to prove deletion?”

“What if someone signs from a shared device—can it be misused later?”

“What if somebody changes document’s timestamp—how do we prove real time?”

“What if a user invokes GDPR deletion but it's legally required?”

“What if two competing clients use iusign—how do you ensure zero leakage?”

“What if our team uses the wrong API key—can data be accessed across tenants?”

“What if someone creates a lookalike domain (sign.c0mpany.com) to phish users?”

“What if your system goes down during a critical signing period?”

“What if we want to leave iusign—can we export everything?”

“What if an API key is leaked—can someone misuse it silently?”

“What if we send to 1000s and some fail—can we retry only failed ones?”

Engineered to outperform.

Full Stack. Zero Bloat.

Visual Document Preparation

Sequential Multi-Party Signing

Immutable Audit Trail

Change Request & Revision Workflow

Full White-Label Capability

Smart Email Delivery

Stuck Document Detection

Security-First API

Infrastructure-Level Trust

AES-256-GCM GCP KMS Envelopes

SHA-256 Hash Chain Integrity

Ephemeral Zero-Persistence Flow

Immutable PDF Flattening

Universal Evidence Package

HMAC-Signed Idempotent Pipelines

Scale bulk sends without jobs failing.

Everything you need to know.

Is IUSign legally binding?

How does the 'Zero-Persistence' security work?

Can I use my own domain for signing?

What is an Immutable Audit Trail?

Does IUSign have a developer API?

Take control of your document logistics.

Architected for
the "Worst Case".

Take control of your
document logistics.