Very interesting to hear about that arb, and the reasons it comes about and persists makes a lot of sense. In addition to the reasons you mention (retail cluel

Very interesting to hear about that arb, and the reasons it comes about and persists makes a lot of sense. In addition to the reasons you mention (retail cluelessness, margin requirements, risk systems), these are some other reasons I can think of as to why the arb persists over time: - Perps are popular on Bitmex/Bybit, and futures are popular on Ok and Huobi (even though the latter has perps, they're relatively illiquid). So there's a cross-exchange dimension which adds more difficulty and risk in performing the arb. - Counterparty risk of keeping funds on an exchange increases the required compensation for performing the arb, which allows it to persist.