According to BitMEX's Q2 2026 report, structural flaws in collateral design drive persistent funding rate disparities across perpetual swap contracts. The exchange's analysis of its bitcoin-margined inverse contract (XBTUSD) versus its USDT-margined linear counterpart (XBTUSDT) showed an average annualized spread of 3.93% over 3.5 years, peaking at 27.6% on April 23, 2026.
Comparing across venues, Hyperliquid maintained a 7.17% annualized Bitcoin funding premium over Binance from 2023 to 2026, with Ethereum perpetuals showing a 5.31% premium. BitMEX attributes the divergence to differing trader demographics and barriers preventing large institutional arbitrage capital from flowing into decentralized platforms. The exchange advises traders to identify whether funding rate gaps stem from long-duration structural factors before deploying arbitrage capital.