Polymarket launches pUSD, CLOB and $1M liquidity boost

Polymarket completed a network upgrade on Tuesday, launching a native pUSD stablecoin and a hybrid central limit order book (CLOB). Trading resumed about an hour after the update and the firm deployed $1 million in additional liquidity to support markets.

Registered users with balances can convert bridged USDC to pUSD automatically on the platform’s front end. Polymarket also released an API that wraps USDC into pUSD for programmatic and API-based traders.

Trading will run on a hybrid CLOB that uses off-chain order matching combined with decentralized, non-custodial settlement. Final transactions will settle on Polygon. Polymarket removed bridged USDC from its front end and replaced it with pUSD, which remains backed by USDC.

The company rebuilt its exchange stack, upgrading to Solidity 0.8.30 and rewriting core services including the order manager, ledger, executor, balance checker and tracker. Orders will be tracked by millisecond timestamps rather than by on-chain nonces.

Josh Stevens, vice president of engineering, DeFi, wrote on X that the company plans to overhaul its team and add observability to monitor errors or unusual events.

Polymarket introduced fees on eligible markets at the time of order matching while keeping markets tied to geopolitical and world events free. Fees will fund a Market Rebates Program to compensate market makers; market takers will supply the fees. Traders reported fees being applied on a per-market basis.

The rebate structure has attracted bot-driven market-making and testing of AI agents using autonomous wallets.

The upgrade follows a period of high volumes. Polymarket reported $8.1 billion in trading volume in April, down from a March peak of $10.6 billion, and peak fees of more than $28 million in April. The platform has about 2.49 million unique users and a cumulative trading volume of roughly $81 billion to date.

Polymarket faces competition from regulated rival Kalshi, which leads in taker volumes with more than $13 billion monthly compared with Polymarket’s roughly $8 billion.

Polymarket completed the upgrade on Tuesday, resumed trading about an hour later and said the added $1 million in liquidity will support markets while the new matching engine and settlement processes come online.