Understanding the Legal-Grade Package

What Legal-Grade Adds

A standard TimeProof timestamp (scheduled or verified instant) proves:

What: The exact file contents (via SHA-256 hash)
When: The exact time (via blockchain anchor)

Legal-Grade adds:

Who: The specific verified account that submitted the file (via JWS identity attestation)
How to verify: A complete guide for legal professionals (verification_guide.txt)
Self-proving chain: Every file in the bundle can be verified independently, without contacting TimeProof

The Evidence Bundle

When you apply Legal-Grade to a timestamp, you receive a ZIP archive containing 7 files:

1. certificate.json

The machine-readable timestamp certificate. Contains:

Original file name and size
SHA-256 hash
Blockchain transaction ID
Block number and timestamp
Polygon network details

Use case: Automated verification systems, structured data for exhibits.

2. merkle_proof.json

The cryptographic proof that your specific file was included in the blockchain anchor.

When multiple files are batched together (especially with Scheduled timestamps), they’re combined into a Merkle tree. Only the tree’s root hash is written to the blockchain. The Merkle proof contains the path from your file’s hash to the root — proving your file’s inclusion without revealing other files.

Use case: Technical verification by expert witnesses or opposing counsel’s technical team.

3. identity_attestation.jws

A JSON Web Signature (JWS) per RFC 7515 that cryptographically binds your verified account identity to the timestamp.

The JWS contains:

Your account identifier
The timestamp reference
TimeProof’s digital signature

Verification: Decode the JWS and verify the signature using TimeProof’s public key, published at /.well-known/jwks.json. This is a standard cryptographic operation supported by any JWT library.

Why JWS? JWS is an IETF standard (RFC 7515) used across the internet for authentication and authorization. It’s well-understood by the security community and has robust verification tooling.

4. identity_readme.json

A JSON document explaining:

What the identity attestation proves
How to verify the JWS
Where to find the public key
What each field in the attestation means

Written for technical readers who need to understand the identity binding mechanism.

5. verification_guide.txt

A plain-text, step-by-step guide for legal professionals. Written without jargon for:

Attorneys presenting the evidence
Judges evaluating the evidence
Opposing counsel verifying the evidence
Arbitrators or mediators reviewing the evidence

The guide walks through:

What is a hash and what does it prove?
How to verify the file hash
How to verify the blockchain timestamp on Polygonscan
How to verify the identity attestation
What the combined evidence proves

6. CHECKSUMS.sha256

SHA-256 hashes of every file in the bundle. This allows verification of the bundle’s own integrity — confirming that no file in the evidence package has been modified.

7. The timestamp certificate (PDF)

The standard visual certificate, identical in structure to what scheduled and verified instant timestamps produce.

How to Present Legal-Grade Evidence

Step 1: Prepare the exhibit

Include:

The original file (the document, photo, or evidence you timestamped)
The complete Legal-Grade ZIP archive
A brief declaration explaining what the exhibit represents

Step 2: Walk through the verification

Using the verification_guide.txt, demonstrate:

The original file’s SHA-256 hash matches the hash in the certificate
The transaction ID exists on Polygonscan with the matching hash
The blockchain timestamp confirms the date
The JWS identity attestation confirms the submitter

Step 3: Offer independent verification

Emphasize to the court that every claim is independently verifiable:

The hash can be recomputed by anyone with a SHA-256 tool
Polygonscan is a public service, not controlled by TimeProof
The JWS public key is published and accessible to anyone
No cooperation from TimeProof is required for verification

When to Use Legal-Grade

Scenario	Need Identity?	Recommendation
Routine file backup	No	Standard scheduled timestamp
Portfolio protection	Maybe	Standard first, LG for key pieces
Contract execution	Yes	Legal-Grade
Evidence preservation	Yes	Legal-Grade
Patent documentation	Yes (for key filings)	Legal-Grade for critical docs
Compliance filings	Depends on regulation	Legal-Grade if auditability required
Whistleblower documentation	Yes	Legal-Grade
Brand asset protection	No	Standard scheduled or verified instant timestamp
Research data integrity	Depends on stakes	Standard for routine, LG for grants/publications

Pricing

Operation	Cost	Notes
Scheduled timestamp	1 credit per file	Available to all users
Instant timestamp	2 credits per file	Requires active verification
Legal-Grade upgrade	Starter and Pro: 50 credits up to 25 files, then +2/file. Business: 25 credits up to 25 files, then +1/file. Enterprise: included.

All three operations draw from one unified balance. One-time packs start at Micro $15 (100 credits), and verified monthly plans start at Starter $19/mo (100 credits). Legal-Grade is applied per batch, not per file, so one upgrade covers the entire anchored job.

Independent Verification Paths

The Legal-Grade bundle provides three independent verification paths that don’t require TimeProof’s involvement:

Path 1: File integrity

Recalculate SHA-256 hash → compare with certificate → match proves file unchanged. Tools needed: Any SHA-256 tool (built into macOS, Linux, Windows PowerShell).

Path 2: Blockchain timestamp

Copy transaction ID → search on Polygonscan → verify hash and timestamp on-chain. Tools needed: Web browser and Polygonscan.com.

Path 3: Identity

Decode JWS → fetch public key from /.well-known/jwks.json → verify signature. Tools needed: Any JWT/JWS library (available in every major programming language).

All three paths produce binary results: match/no match, valid/invalid. There’s no subjectivity, no interpretation, no expert opinion required. The evidence either verifies or it doesn’t.