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Market Makers Overview

Market makers on Openfish maintain standing bid and ask orders in prediction markets, providing the depth that lets other participants open and close positions without excessive slippage. In exchange for this service, market makers collect the bid-ask spread, qualify for liquidity rewards, and receive maker rebates.


  • Zero maker fees — Makers never pay trading fees on Openfish.
  • Maker rebates — Earn tiered daily USDC rebates based on your maker volume. See Maker Rebates.
  • Liquidity rewards — A separate incentive pool distributed daily to liquidity providers who keep tight, two-sided quotes. See Liquidity Rewards.
  • Capital efficiency — Negative risk markets let you collateralise positions across multiple outcomes with a single deposit. See Negative Risk.
  • RFQ flow — Large block traders submit Requests for Quote that only market makers can respond to, giving you first look at institutional flow.

  1. Complete setup — Fund your wallet with USDC.e on Polygon, approve exchange contracts, and generate API credentials. See Getting Started.
  2. Connect to data feeds — Subscribe to the WebSocket for real-time orderbook updates and the Gamma API for market metadata. See Market Data.
  3. Start quoting — Post limit orders via the CLOB REST API. See Trading.

ActionToolDocumentation
Deposit USDC.eBridge APIBridge
Approve tokensRelayer ClientGetting Started
Post limit ordersCLOB REST APITrading
Monitor orderbookWebSocketMarket Data
Split USDC.e into tokensCTF ContractInventory
Merge tokens to USDC.eCTF ContractInventory
Respond to RFQsRFQ APIRFQ
Check rebatesCLOB REST APIMaker Rebates

  • Getting Started — Wallet setup, deposits, token approvals, and API key creation.
  • Trading — Order types, batch submission, cancellation strategies, and best practices.
  • Inventory Management — Split, merge, and redeem outcome tokens to keep your books balanced.
  • Liquidity Rewards — How the reward program works, the scoring formula, and daily distribution.
  • Maker Rebates — Volume-tiered BPS rebates paid daily in USDC.

Quoting prediction markets carries tangible risk. A crossed book — where your bid exceeds your ask — means every fill loses money. Always validate quote prices against current market conditions before submission, and wire up a kill switch that fires cancel_all the moment you detect anomalous fills, position limit breaches, or connectivity degradation.


For market maker onboarding and technical support, contact support@openfish.fun.