L1 Signature
An EIP-712 signature from the root EOA wallet used to authenticate high-privilege CLOB API operations like API key registration.
Definition
An L1 signature is a cryptographic signature generated by an Ethereum externally-owned account (EOA) — a wallet controlled directly by a private key, with no smart-contract intermediary. On Polymarket, L1 signatures are used for operations that require the highest level of authority, such as registering API keys, linking a proxy wallet, or accessing CLOB endpoints that require full wallet ownership proof.
In practice
During initial bot setup, the bot signs an L1 message using the root private key (via ethers.Wallet from the private key in secrets.json) to register or derive the API credentials with Polymarket. After this one-time setup, all routine order operations use L2 signatures from the lighter-weight API key. Because L1 signatures expose the root wallet's signing capability, the private key should never be present in production bot runtime configs. The ClobClient initialization flow handles L1 registration automatically when credentials are first derived.