03 Sl SEAL Hash Vault

⚠ Your Files Can Be Modified Without Your Knowledge

If it can be changed,
it's safe it can be falsified.

Contracts. Evidence. Source code. Financial records. Any file on any drive.

A document that can be modified and shared as original is a document that cannot be trusted. Digital files carry no memory of being changed. Without a cryptographic proof of what existed at a specific moment in time — you have nothing.

1,293,847 Files modified without detection globally today █
See the Solution See the Threat
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BlackBox Seal · Live Preview

See It Running

Register a document. The hash is your proof. Any modification breaks the seal.

BlackBox|Seal
Documents
invoice_Q1_2026.pdf
contract_amended.docx
env_report_final.pdf
site_brief_v3.pdf
nda_pending.pdf
Summary
4 verified 1 tampered
invoice_Q1_2026.pdf
Registered 2026-03-18 · SHA-256
✓ VERIFIED
Cryptographic Hash · Matches
a3f9c2e1b847d56f12340abcd9876543ef218abc901234def56789012345678901234567890
Sealed At
2026-03-18 · 09:41:22 UTC
Verified At
2026-03-22 · 14:03:07 UTC
File Size
84,220 bytes · Unchanged
Algorithm
SHA-256 · Tamper-proof
⚠ contract_amended.docx — HASH MISMATCH
Registered hash does not match current file. Document was modified after sealing. Do not authorize payment.
🔒
Cryptographic Proof
SHA-256 hash registered at the moment of document finalization. Mathematically impossible to fake.
⚠
Tamper Detection
Any modification — even a single byte — breaks the seal. Hash mismatch triggers an immediate alert before any action is taken.
📋
Audit Trail
Every seal event is timestamped. Exportable certificate provides legal-grade chain of custody for compliance and litigation.

The Threat Is Undetectable

A modified file looks
identical to the original.

There is no visible difference between a contract that has been altered and one that has not. Without a cryptographic hash anchored to an immutable record, you cannot prove a file's integrity — to yourself or to anyone else.

$4.2B
Lost annually to document fraud
Contract manipulation, evidence tampering, and forged records cost organizations billions annually. The attack surface is any digital file. The defense requires cryptographic proof.
0sec
Time to modify a file
Any text editor, hex editor, or file system command can alter a file in under a second. Modified timestamp can be reset. No trace left. No alarm triggered.
99%
Of organizations have no file integrity system
Hash-based integrity verification exists in enterprise security tools — but almost no individual or small organization uses it. The technology gap is the exploit.
∞
Ways to modify a file undetected
Bit flip. Whitespace change. Invisible Unicode character. Metadata edit. Any of these produces a different file that looks identical and carries no signature of having been changed.
📋
Contract Manipulation
A PDF contract sent for signature can be modified after signing in certain configurations. A single character change in a clause — dollar amount, date, party name — is invisible without a hash comparison against the original.
SHA-512: [original] ≠ SHA-512: [received] · TAMPERED
🔬
Evidence Tampering
Digital photographs, audio recordings, and documents submitted as evidence in legal proceedings carry no inherent proof of originality. Anyone with file access can alter them. Chain of custody requires cryptographic proof.
No hash record found · File integrity: UNVERIFIED
💾
Supply Chain Attacks
Software distributed without cryptographic signatures can be silently replaced with malicious versions. A binary that looks identical to the original — same size, same name — can contain entirely different code.
installer.exe · modified: 2026-03-14 · hash: UNVERIFIED
📁
Version Drift
When a file is shared across teams, clouds, and devices — edits accumulate without a canonical reference. Which version is the authoritative original? Without sealing the original, there is no answer.
contract_v3_final_FINAL2.docx · last modified: unknown

Proof that a file existed,
unchanged, at a specific moment.

Seal generates a SHA-512 cryptographic hash of your file — a mathematical fingerprint that changes if a single bit changes — and anchors it to the Bitcoin blockchain via a public timestamp. The record is permanent. The proof is yours.

When you need to prove a file's integrity — in court, in contract, in code — you run Seal's verifier. The hash either matches or it doesn't. There is no ambiguity.

∩R = {Ψ(i)} · The Cunningham Loop · The invariant that doesn't change

How It Works

Hash. Anchor. Vault. Verify.

Seal computes a cryptographic fingerprint of your file, anchors it to the Bitcoin blockchain, stores the chain of custody locally, and gives you an instant tamper verdict on demand.

01 · Hash
Cryptographic fingerprint
Seal computes a SHA-512 or SHA-256 hash of your file — a 128-character fingerprint that is mathematically unique. If a single bit changes, the hash changes.
SHA-512 / SHA-256
02 · Anchor
Bitcoin blockchain timestamp
Seal fetches the latest Bitcoin block hash and creates an anchor hash combining your file hash, the block hash, and a local timestamp. The blockchain is your witness.
Immutable record
03 · Vault
Seal stored locally
The hash, timestamp, blockchain anchor, and chain-of-custody log are stored in your local vault. Every subsequent verification is appended to the record.
Chain of custody
04 · Verify
Tamper detection
Drop the file. Seal recomputes the hash and compares it to the stored record. INTACT or TAMPERED — in under a second. Export a standalone HTML verifier anyone can use offline.
Instant verdict

BlackBox | Seal

SHA-512 · Bitcoin Anchor.
Mathematical proof of integrity.

Seal uses streaming SHA-512 computation for large files, Bitcoin blockchain anchoring via mempool.space, and an append-only chain-of-custody log per sealed file. No external services required for verification.

Technical Specification · Seal v1.0

Hash Algorithm
SHA-512 · SHA-256 (selectable)
Hash Output
128 hex characters (SHA-512)
Timestamp
Bitcoin blockchain · mempool.space
Anchor
SHA-256(fileHash + blockHash + localTs)
Fallback
Local timestamp if network unavailable
Storage
electron-store · local JSON vault
Batch Sealing
Entire folder · root hash manifest
Chain of Custody
Append-only event log per entry
Export Formats
.seal JSON · standalone HTML verifier
Verifier
browser Web Crypto API · no install
Streaming
Large file support via ReadStream
Platform
Windows · Electron

Seal & Verify Sequence

From file drop to blockchain-anchored proof — and back to verified integrity.

📂
File dropped
Single file or entire folder dropped onto the Seal interface
Any file type
⚡
Hash computed
Streaming SHA-512 reads the file in chunks — handles files of any size without loading into memory
Streaming SHA-512
⛓
Blockchain anchored
Latest Bitcoin block hash fetched. Anchor hash computed. Timestamp recorded with block proof.
Bitcoin witness
🏛
Vault entry created
Hash, anchor, timestamp, and initial custody event written to local vault. Chain of custody begins.
Chain of custody
✓
Verification ready
Drop the file anytime. Seal recomputes and compares. INTACT or TAMPERED. Export .seal or HTML verifier.
Instant verdict
"A hash is not a seal.
An anchor is."

BlackBox | Seal · Luminous.Works

Pricing

Proof costs less
than the alternative.

A tampered contract. A forged document. An unsealed file no court will accept. Seal costs less than one legal dispute — and the blockchain record is permanent.

Personal
$7.99
per month · unlimited files
Hash, anchor, and verify any file. Unlimited sealing. Local vault. Standalone HTML verifier included with every sealed file.
  • Unlimited file sealing · any format
  • SHA-512 + Bitcoin blockchain anchor
  • Local chain-of-custody vault
  • Standalone HTML verifier export
  • Batch sealing · folder support
  • Personal use · 1 device
Request Access
Professional
$24/mo
per user · shared team vault
Shared vault, team batch sealing, and compliance-ready export formats. Built for legal, finance, and procurement teams.
  • Everything in Personal
  • Shared team vault
  • .seal JSON · PDF audit report export
  • Priority support · 24h response
  • Red Team Certification eligible
  • 2–20 users
Request Access
Enterprise
Custom
org-wide · compliance-grade
Ministry and institution-grade deployment. Caribbean data residency. CNSA 2.0 audit documentation. SLA-backed with dedicated onboarding.
  • Everything in Professional
  • Caribbean data residency
  • CNSA 2.0 audit documentation
  • SLA guarantee · custom uptime
  • Dedicated onboarding engineer
  • 50+ users · volume pricing
Contact Sales
Special Access Tiers
Discounts are application-based and manually verified. Not self-declared. Not automatic. Apply with your credentials — we respond within 48 hours.
🗞
Press & Journalism
Verified press access — any newsroom, any circulation, any country. Two reporters at a local weekly paper qualify exactly as much as a national bureau. The credential is what matters, not the masthead. Seal your sources. Protect your evidence. Prove your record.
Verified Press · Full Suite · 15% of suite price Apply with press credentials →
🌍
NGO & Civil Society
Document integrity is a human rights tool. Verified NGOs receive increasing discounts as deployment scales. Access requires registration documents. Self-declaration is not accepted — every application is reviewed manually.
Verified NGO · Professional −25% · Enterprise −40% · 100+ seats −50% Apply with registration documents →
🎓
Academic & Research
Accredited universities and research institutions receive the same tiered structure. Institutional email and department verification required. Seal your research data. Prove it hasn't changed. Application reviewed within 48 hours.
Verified Academic · Professional −25% · Enterprise −40% · 100+ seats −50% Apply with institutional credentials →

Seal it. Prove it. Forever.

Seal is part of the BlackBox Suite. Hash any file. Anchor it to the Bitcoin blockchain. Verify it anywhere — with the standalone HTML verifier that needs no installation and no internet.

Request Early Access View Full Suite

✓ SHA-512 · ✓ Blockchain anchored · ✓ Chain of custody · ✓ Offline verifier