The simple explanation
Imagine you write down an invention idea today. Six months from now, someone else files a patent for the same concept. How do you prove you thought of it first?
Proof of existence solves this. You take your document, compute a cryptographic fingerprint (SHA-256 hash), and record that fingerprint on a public blockchain. The blockchain timestamp becomes permanent, immutable evidence that your document existed at that exact moment.
Crucially, the document itself is never uploaded. Only its hash. No one can read what your file contains.
How it works technically
- You select a file (design spec, code, invention description, contract draft, etc.)
- Your browser computes a SHA-256 hash of the file locally — the file is never sent to any server
- The hash is submitted and included in a blockchain transaction
- The transaction is confirmed on-chain, creating a permanent timestamp
- You receive a PDF certificate with the hash, timestamp, block number, and transaction ID
- To verify later: anyone rehashes the original file and checks if the hash matches the certificate
Why it matters
Private by design
Your file never leaves your device. Only a cryptographic fingerprint goes on-chain — mathematically impossible to reverse.
Immutable timestamp
Once written to the blockchain, the record cannot be altered, backdated, or deleted — by anyone, including the service provider.
Legally relevant
Courts and patent offices recognize blockchain timestamps as prior art evidence. It does not replace a patent, but it strengthens your position dramatically in any priority dispute.
Publicly verifiable
Anyone can verify your proof using just the original file and a certificate ID — no trust in any third party required.
Who uses proof of existence?
| Who | Why |
|---|---|
| Inventors & startup founders | Establish prior art before sharing with investors or contractors |
| Designers & creatives | Prove original authorship before publishing or pitching clients |
| Software developers | Timestamp algorithm specs before open-sourcing |
| Legal & compliance teams | Create audit trails for contracts and regulatory submissions |
| Researchers & academics | Establish priority before formal publication |
Proof of existence vs. a patent
These serve very different purposes.
A patent grants exclusive rights to an invention — but filing takes 1–3 years and costs $5,000–$15,000+, and requires disclosing how your invention works.
Proof of existence simply proves you had the idea first, without revealing it. Think of it as locking a sealed envelope in a tamper-proof vault with a certified date — before you show it to anyone.
The two are complementary. Smart inventors use proof of existence during ideation and development, then file a patent when ready to go public.
Getting started
Services like Patent.rocks offer blockchain-anchored proof of existence starting at $5 per proof. The process takes about 2 minutes:
- Create an account
- Drag and drop your file
- Pay with crypto (USDT, BTC, ETH)
- Download your blockchain-anchored certificate
There's no reason to wait until you can afford a patent attorney. Timestamp your idea today.
This article was originally published at patent.rocks/en/what-is-proof-of-existence
