Polymarket has launched Protocol V2, a complete rebuild of its prediction market smart contract infrastructure designed to replace the legacy Gnosis Conditional Tokens Framework from 2019. The new system adopts a modular architecture utilizing ERC-1155 position tokens and pUSD collateral, supporting Binary, Atomic Neg-risk, Incremental Neg-risk, and Combinatorial market types while reducing system complexity. The upgraded protocol introduces an OracleAggregator for connecting multiple settlement sources like UMA and Chainlink, alongside cross-chain support for future multi-chain expansion. The codebase has undergone audits by Cantina, Certora, Quantstamp, SigmaPrime, Zellic, and Pashov, and passed formal verification by Certora. Test markets will run through October 30, with new markets tentatively switching to V2 starting November 2.