LIVEFull-depth Polymarket Up or Down order books for Bitcoin, Ethereum, Solana, XRP, BNB and Dogecoin, with the Chainlink price each market settles on.
The signature type tells Polymarket's exchange which wallet arrangement is signing an order — a plain externally owned account, the proxy wallet created by the Polymarket interface, or a Safe-based smart wallet. Sending the wrong type causes signature validation to fail even when the signature itself is correct.
Per the setup documented in our build guide, type 1 corresponds to the Polymarket-UI proxy arrangement and type 2 to Safe-based smart wallets. Match the type to how the account was actually created rather than copying a value from an example.
API keys are bound to the address that derived them, which is a related trap: a key generated by one address cannot be used to trade another account's positions without the correct funder and signature type in place.
Copying a signature type out of an example rather than matching how the account was actually created. The signature itself is valid, so the error looks like a signing bug rather than a configuration one.
Browse the full glossary (32 terms), the strategy database, or the build guides.