Prove you
created it first.

Cryptographic timestamps that hold up when it matters. We seal your files with a verifiable timestamp and give you the only key.

We believe that ownership begins with the creator and that proof should too.

How it works

It happens fast

The freelancer: You deliver mockups to a client. They ghost you. Three months later, you see your exact designs on their website — and they're refusing to pay.

The developer: You share your algorithm with a potential partner. They pass. Six months later, their "new feature" looks awfully familiar.

The author: You send your manuscript to a publisher. They reject it. A year later, a suspiciously similar book hits the shelves.

The contractor: You finish the project on time. The client claims you were late to avoid the final payment.

You know you created it. You know when you delivered it.
But can you prove it?

Current solutions fall short

Email to yourself Headers can be forged. Courts know this.
Screenshots Trivial to edit. No cryptographic proof.
Cloud storage timestamps Controlled by the provider. They can change.
Notarization Expensive, slow, limited to physical documents.

Our solution

SoulProp creates a cryptographic seal around your files. We request a timestamp from an independent authority (not us), encrypt your files so only you can open them, and store it securely.

You get a key file. This is the only copy — we don't keep it. When you need to prove when you created something, return with your key. We'll decrypt your files and provide a complete evidence package.

We never see your content. Your files are encrypted the moment they arrive, before any human could access them. The key is generated and given only to you — we never store it. Without your key, we cannot read what you sealed. Not now, not ever. Your work stays "prop" — proprietary to you alone.

RFC 3161 Industry standard timestamp, used in legal proceedings worldwide
Zero knowledge Your files are encrypted. Without your key, we can't see them.
Verifiable Anyone can independently verify the timestamp — no trust required

Why not blockchain?

NFTs and blockchain timestamps require wallets, gas fees, and chain-specific infrastructure that may not exist in 10 years. RFC 3161 timestamps are legally recognized, universally verifiable, and work with standard tools — no crypto expertise required.

Seal a book's worth of text for $7.

Priced for accessibility, not exclusivity.

Seal your work

How it works

When you seal

  1. Upload your files Documents, code, designs, contracts — anything you create. Size limit depends on your tier (500 KB to 100 MB). Multiple files are bundled automatically.
  2. We encrypt and timestamp Your files are compressed and encrypted with XChaCha20-Poly1305. We compute a SHA-256 fingerprint and request an RFC 3161 timestamp from an independent authority.
  3. Download your key file You receive a .soulprop file containing your decryption key. This is the only copy — we don't keep it. Store it somewhere safe.

Your key is irreplaceable. Without it, your files stay sealed forever. Back it up to cloud storage, a USB drive, or anywhere you won't lose it.

When you need proof

  1. Return with your key file Come back to SoulProp and upload your .soulprop key file. This proves you have the right to reveal the seal.
  2. We decrypt and verify Your original files are decrypted and the timestamp is cryptographically verified against the independent authority's records.
  3. Download your evidence package A complete package containing your original files, the RFC 3161 timestamp token, a PDF certificate, and verification scripts anyone can run independently.

No trust required. The evidence package lets anyone verify your timestamp without relying on SoulProp. The cryptographic proof stands on its own.

See it for yourself

Walk through the full experience with a sample document. See exactly what you get — the sealing process, your key file, and the evidence package.

Watch the demo

2-3 minutes

Who uses this

Creators protecting original work before sharing with collaborators

Authors timestamping manuscripts and books before submission

Developers timestamping algorithms and code before open-sourcing

Inventors documenting prior art before patent filings

Businesses proving when contracts and deliverables existed

Ready to seal?

Starting at $7. No account needed. Proof in minutes.

Seal your work