EIP-712 Explained: How Signed Orders Protect Your Funds
EIP-712 lets you sign a readable, structured message instead of blind-signing hex. Here's how it keeps non-custodial trading safe and verifiable.
Every non-custodial trade rests on one action: you sign a message. EIP-712 is the Ethereum standard that makes that signature safe to give — readable, scoped, and impossible to tamper with. Here’s how it works without the cryptography jargon.
The problem EIP-712 solves
Early crypto signing was dangerous. Wallets asked you to sign a blob of hex you couldn’t read. You had no way to know if you were authorizing a $10 trade or draining your wallet — you were blind-signing. Malicious apps abused exactly that.
EIP-712 fixes it by signing structured, typed data: a message with named fields your wallet can display in plain language. Instead of 0x9fa3..., you see the actual order — token, price, size, side — before you approve.
What gets signed in a trade
When you place an order on a non-custodial platform like Pots Market, your wallet shows you a structured order and you sign it with your private key. That signature authorizes that exact order and nothing else:
Order
token: YES (Will event X happen?)
side: BUY
price: 0.62
size: 100
maker: 0xYourAddress
Three properties make this safe:
- Readable — you see the real terms, so you can’t be tricked into signing something else.
- Scoped — the signature covers only this order’s fields. Change any of them and the signature is invalid.
- Domain-bound — EIP-712 includes a “domain” (chain, contract, app), so a signature meant for one contract can’t be replayed on another.
Why it makes trading non-custodial
Because the order is signed by your key and verified on-chain, no intermediary can alter it. The application routes your signed order to the settlement contract, but it can’t change the price, flip the side, or inflate the size — any edit breaks the signature. And it never holds your funds; settlement happens directly on-chain. That’s what makes the whole model non-custodial.
On Pots Market, orders settle through Polymarket’s audited CTF Exchange on Polygon, and each carries an on-chain attribution code — so you can verify your order was routed correctly, not just trust that it was.
What to still watch for
EIP-712 secures the order, not your whole wallet:
- Read every signature prompt. The standard makes terms visible — actually look at them.
- Check the domain. Confirm the contract/app matches where you intend to trade.
- Revoke stale approvals. Token approvals are separate from order signatures; review them periodically.
The takeaway
EIP-712 turns a dangerous blind signature into a readable, tamper-proof authorization. It’s the quiet standard that lets you trade without handing over custody — you sign exactly what you mean, and the chain enforces it. See how it fits the full Pots Market security model.