Hyperliquid has launched its Outcome Tokens fee structure, marking a significant step towards its mainnet launch and positioning itself against prediction market leaders Polymarket and Kalshi. The new structure eliminates fees for opening positions, charging only upon closing or settlement. Users trading with the platform's "aligned quote token" benefit from a 20% reduction in taker fees and a 50% increase in maker rebates. This launch coincides with the HIP-4 upgrade, allowing binary contract trading on real-world events alongside existing perpetual and spot positions. The timing of Hyperliquid's launch is strategic, as Polymarket recently announced the upcoming introduction of perpetual trading. The prediction market industry has seen substantial growth, with trading volumes surging over 300% year-over-year in 2025, reaching $63.5 billion. Currently, Hyperliquid's Outcome Tokens are in the testnet phase, with the mainnet launch date yet to be announced.