Contract Proof
Prove exactly what was signed and when.
Cryptographic attestation for contracts, signatures, and amendments — immutable evidence that survives legal challenges.
Trusted by legal teams at
Contract Disputes Cost Billions
Without cryptographic proof, contracts become "he said, she said" in court
Version Disputes
"That's not the version I signed" — parties dispute which contract version was actually agreed upon.
$12B lost annually to disputes
Timestamp Challenges
"They backdated the signature" — without independent timestamps, signature dates can be disputed.
35% of disputes involve timing
Amendment Confusion
"I never agreed to that amendment" — amendment chains become impossible to verify years later.
Average dispute: $2.4M
Cryptographic Proof for Every Contract
Contract Proof creates an immutable, timestamped record of every document version and signature
Certify Documents
Upload contract documents. We create a SHA-256 fingerprint proving exactly what content was agreed upon.
Record Signatures
Capture signer identity, IP address, and consent. Each signature gets its own cryptographic attestation.
RFC 3161 Timestamp
Receive a legally-binding timestamp certificate proving exactly when each party signed — from an independent authority.
Track Amendments
Link amendments to original contracts. Maintain complete version history with cryptographic proof.
{
"certificate_id": "cert_contract_8x7k2m",
"contract": {
"title": "Master Services Agreement",
"version": "2.0",
"document_hash": "sha256:7d8a9b2c...",
"parties": ["Acme Corp", "Widget Inc"]
},
"signatures": [
{
"signer": "john@acme.com",
"role": "CEO",
"timestamp": "2024-12-15T10:30:00Z",
"ip_address": "203.0.113.42",
"certificate_id": "cert_sig_a1b2c3"
},
{
"signer": "jane@widget.com",
"role": "CFO",
"timestamp": "2024-12-16T14:15:00Z",
"ip_address": "198.51.100.73",
"certificate_id": "cert_sig_d4e5f6"
}
],
"timestamp": {
"rfc3161": true,
"tsa": "DigiCert",
"signature": "MIIEpAIBAAKCAQ..."
},
"verification_url": "certnode.io/v/8x7k2m"
}Complete Contract Evidence Suite
Everything you need to prove contract authenticity in court
Document Certification
SHA-256 fingerprint of every document version. Prove the exact content that was signed — byte for byte.
Signature Attestation
Cryptographic proof of who signed, when, and from where. Each signature independently verifiable.
RFC 3161 Timestamps
Legally-binding timestamps from accredited authorities. Self-authenticating under FRE 902(13-14).
Amendment Chains
Link amendments to originals. Complete version history with cryptographic proof of each change.
Public Verification
Share verification links with opposing counsel. No account required — anyone can verify authenticity.
Evidence Packages
One-click export for litigation. PDF certificates ready to submit to courts and arbitration panels.
Built for Legal-Grade Documentation
From startups to enterprises, protect your agreements
M&A Transactions
Prove exactly what was agreed in acquisition documents. Protect against post-closing disputes.
- LOI and term sheet certification
- Definitive agreement versioning
- Disclosure schedule attestation
Real Estate
Prove purchase agreement terms years after closing. Protect against buyer/seller disputes.
- Purchase agreement certification
- Disclosure attestation
- Amendment tracking
Employment Agreements
Prove employment terms, non-competes, and equity grants. Protect against wrongful termination claims.
- Offer letter certification
- Equity agreement attestation
- Policy acknowledgment tracking
Vendor Contracts
Prove SLA terms and pricing agreements. Protect against vendor disputes and scope creep claims.
- MSA certification
- SOW versioning
- Change order tracking
Simple, Transparent Pricing
Pay per contract. No hidden fees.
Startup
For small legal teams
- 100 contracts/month
- Signature attestation
- RFC 3161 timestamps
- Basic API access
Business
For growing legal teams
- 1,000 contracts/month
- Amendment chains
- Evidence export
- Priority support
Enterprise
For large legal departments
- Unlimited contracts
- CLM integration
- Litigation support
- Dedicated support
Don't Wait for the Dispute
Start certifying your contracts today. When litigation comes, you'll have verifiable proof of exactly what was agreed.