Copyright Guides

Blockchain Timestamping Guide

Every file deposited on Copyright01 is anchored on the Polygon blockchain. This guide explains how this anchoring works, why it strengthens your proof of authorship and how to verify it yourself.

8 min read Updated: March 2026
Blockchain Timestamping Guide

What is a digital fingerprint?

A digital fingerprint (or hash) is a unique mathematical signature computed from a file. Copyright01 uses the SHA-256 algorithm, the same as Bitcoin. Any modification, even a single character, produces a completely different fingerprint.

This property guarantees your file's integrity: if the fingerprint matches, the file has not been altered since deposit.

SHA-256 hash simulator

SHA-256 fingerprint

Change a single character: the fingerprint changes completely.

Good to know

A SHA-256 fingerprint is always 64 hexadecimal characters, regardless of the source file size. A 500-page novel and a 10-word tweet both produce a 64-character fingerprint.

Traditional vs blockchain timestamping

Several methods can timestamp a file. Here is how they compare.

Traditional vs blockchain timestamping
Criteria Server (Copyright01) Notary / Bailiff Polygon Blockchain
Cost Free (3 deposits included) EUR 50 to 300 per deed 0 POL (network fees only)
Speed Instant (< 5 seconds) Appointment required (days/weeks) ~2 seconds (1 Polygon block)
Verifiability Verification code + QR code Paper document, manual verification Public, verifiable by anyone on Polygonscan
Independence Depends on Copyright01 Depends on the professional Decentralized, 3,200+ validators
Legal value Opposable proof of anteriority Authentic deed, maximum evidentiary value Proof of existence at a given date

Good to know

Copyright01 combines all three approaches: server anchoring (PDF certificate), blockchain anchoring (Polygon transaction) and online-verifiable certificate. Triple proof.

How Copyright01 anchors your files

The anchoring process is fully automatic. No blockchain knowledge is required.

cloud_upload

File upload

You upload your work (image, text, code, music, video or any other format).

folder_zip

Certified Folder (ZIP)

A ZIP folder is created containing your original file and a proof manifest (who, when, what).

fingerprint

SHA-256 fingerprint of the ZIP

The unique cryptographic fingerprint of the Certified Folder is computed. This is the hash that will be anchored on the blockchain.

link

Polygon transaction (0 POL)

A 0 POL transaction is sent on Polygon with the hash in the data field. No smart contract involved.

verified

PDF certificate with hash and Polygon transaction

Your PDF certificate includes the blockchain transaction hash, verifiable by anyone on Polygonscan.

Key takeaway

The blockchain anchoring is a 0 POL self-transaction. Your file's hash is written in the transaction's data field. Simple, verifiable and permanent.

The blockchain runs 24/7

The Polygon network produces a new block every ~2 seconds, 24 hours a day. Each block is validated by over 3,200 independent validators distributed around the world.

Connecting to Polygon network...

Network unavailable, reload the page.

Block

#

mined s ago
3,200+ validators

Your fingerprint is secured by this network, around the clock.

Good to know

Every transaction on Polygon is irreversible. Once your fingerprint is written in a block, it cannot be modified, deleted or tampered with.

Frequently asked questions about blockchain timestamping

Blockchain timestamping consists of writing a file's digital fingerprint (hash) into a blockchain transaction. The block's date serves as a certified timestamp, proving the file existed at that precise moment.

Copyright01 uses Polygon (formerly Matic), a layer 2 blockchain compatible with Ethereum. It offers fast transactions (~2 seconds), near-zero fees and a network of over 3,200 validators.

No. Blockchain anchoring is a complement to the Copyright01 certificate. Your proof of anteriority is valid even without blockchain anchoring, thanks to the SHA-256 fingerprint and server timestamp.

Open polygonscan.com and paste the transaction hash (tx hash) shown on your PDF certificate. You will see the date, the fingerprint in the Input Data field and the block confirmation.

No. Blockchain anchoring provides proof of existence at a given date. A notarized deed remains the strongest proof under French law. However, blockchain anchoring is instant, free and publicly verifiable, making it a relevant complement.

Blockchain anchoring is included in the Copyright01 subscription at no extra cost. Free and pack users get the SHA-256 fingerprint and Certified Folder, but not the Polygon anchoring.

Test your blockchain knowledge

Question of

/

Thanks for participating! You now understand blockchain timestamping.

What does blockchain anchoring prove?

That you are the legal owner of the file

That a fingerprint existed at a specific date

That the file is stored on the blockchain

Blockchain anchoring proves that a fingerprint (hash) existed at a specific date. It does not store the file itself and does not grant ownership rights, it provides proof of anteriority.

Can a Polygon transaction be modified after the fact?

Yes, with the wallet's private key

Yes, by paying additional fees

No, transactions are irreversible

Blockchain transactions are immutable. Once confirmed in a block, a transaction cannot be modified, cancelled or deleted by anyone.

Do you need a crypto wallet to use Copyright01?

Yes, a MetaMask wallet is required

Yes, you need to buy POL tokens

No, everything is automatic

Copyright01 handles blockchain anchoring transparently. You don't need a crypto wallet, tokens or any technical knowledge. The process is fully automatic.

Sources and references

The information in this guide is based on the following technical resources:

Related guides

Protect your creations

Automatic blockchain anchoring, PDF certificate and opposable proof of anteriority.