Security and proof
If it ever comes to a dispute, you'll have a signed, dated record of what was agreed. Anchor it, and its fingerprint sits in a dated Polygon transaction we don't control. Any later change to the record would no longer match it.
How it works
From first draft to final proof
Here's the full path of a TrustChain agreement, from the first draft to proof you can show in a dispute. Anchor the record, and its fingerprint and date rest on a public blockchain instead of on trusting us.
You write it down
You put the terms in plain words and invite the other person. Once you both have accounts, you can talk it through in a chat on the agreement that's end-to-end encrypted. The keys live on your devices, not on our servers, so only the people in the chat can read it. Not even us.
You sign the agreement
Both of you sign after verifying your identity, and each signature is logged with its time. We store the agreement so TrustChain can work, and it goes to OpenAI only when you ask AI Advisor or Pip for help with it.
Anchoring computes a fingerprint
When you anchor a signed record, we work out a short code, its fingerprint, from its ID, title, terms, amount and both parties' account IDs. The same inputs always give the same code; change a single character and it comes out completely different.
It's written to Polygon
That code and the record's ID are written to Polygon in a dated transaction. If the record changed later, it would no longer match that entry, and anyone can look it up on Polygonscan.
Your data
What stays private. What goes public.
Your agreement has three layers: what's sensitive, what keeps the service running, and the small piece that goes public if you anchor. Here's where each one lives.
Visible to the parties
Stored by TrustChain so the service can work. Never made public.
- Full agreement text
- Terms and conditions
- Negotiated clauses
Maintained by TrustChain
Data that keeps the service running. The public link shows status and signing dates, never who you are.
- Signature states
- Timestamps
- Agreement status
On Polygon, if you anchor
Anyone can look it up on Polygonscan, no account needed.
- The fingerprint
- TrustChain's internal ID for the agreement
- The date and time of the anchor
- Two empty wallet slots
No agreement text, names or emails go on-chain. Anchoring writes the agreement's fingerprint and its TrustChain ID. The two wallet slots in the transaction stay empty: you never connect a wallet.
When it matters
If a client refuses to pay
The work is done, and the client won't pay, or says you agreed to something different. Here's what happens next.
You open the agreement you both signed
It sits in your TrustChain account exactly as both sides signed it. Neither party can edit the terms after the fact.
You share its public link
Anyone can open it without an account and see that both sides signed, and when. Nothing private is shown.
If it was anchored, the date is public
Its fingerprint sits in a Polygon transaction with its own timestamp, so a later change to the record would no longer match it.
A different version has to explain itself
If the other side brings a copy that says something else, you can point to the record you both signed and its dated Polygon entry.
You don't need anyone to take your word for it. You have the signed record.
Under the hood
For the technically minded
If you want the specifics, here they are.
Open source
Check it without us
The anchor contract's source and a read-only checker are open on GitHub under the MIT licence. With Node.js 18 or newer, these commands check our sample record, a test deal we made ourselves, against Polygon. The checker needs no account and no keys.
git clone https://github.com/TRUSTCHAIN-creator-KK/trustchain-protocol.git
cd trustchain-protocol
node verify/bin/trustchain-verify.js 5c79fbb0Read the code on GitHub · What each check does · Open the sample record
What you can check without us
- The fingerprint was written to Polygon by TrustChain's anchoring wallet, at that block's time.
- The contract still holds that fingerprint, and it has no function to change or delete an entry.
- The contract's code on Polygon matches the source published on GitHub.
What rests on our word
- Who the people are, and that both of them signed. Signatures and their times come from TrustChain's records.
- That a record ID belongs to that anchor. The 8-character record ID isn't written on-chain, and TrustChain's public record links the two.
- What the fingerprint was made from, unless you hold the record file. Either person on an anchored agreement can download it from its Proof tab.
Common questions
Questions people ask
Can TrustChain read my agreement?
Your agreement is stored so TrustChain can work, so yes, technically we can access it. It goes to OpenAI only when you ask AI Advisor or Pip for help with it (see Privacy, section 5). Your chat is the exception: it's end-to-end encrypted, so only the people in the chat can read the messages. Not us.
Can someone turn a fingerprint back into my text?
No. The fingerprint is one-way, so your text cannot be reconstructed from it.
What if I lose my copy of the agreement?
Your agreement is stored in your TrustChain account, so you can retrieve it there at any time. If the record was anchored, its fingerprint and date also stay on Polygon even if every copy of the text were lost.
Who do you share my data with?
Only with the services that run TrustChain: Sumsub for identity checks, Stripe for payments, OpenAI when you ask AI Advisor or Pip for help, an email service that delivers invites, Google Firebase, and the analytics you opt into. We don't show ads on TrustChain.
TrustChain security
TrustChain isn't a law firm and doesn't give legal advice. For questions about enforceability, talk to a qualified professional where you live.
Found a security problem? Email founder@trustchain.biz with Security in the subject.