Some Kraken futures limit orders can still fill after a successful cancel

Some Kraken futures limit orders can still execute after a successful cancellation if the cancel arrives during the Maker Protection hold window. Kraken expanded the system on Oct. 8, bringing that order-handling rule to more contracts.Kraken completed Phase 2 after announcing 61 additional perpetual contracts. Maker Protection applies to selected futures markets; Kraken’s documentation describes an initial 20-millisecond hold.What a Kraken futures cancellation changesMaker Protection holds orders that can take liquidity before they reach the matching engine, giving traders with resting orders time to react. A limit order without a post-only instruction is held on a covered market even if it would otherwise have rested on the book.A cancel inside that window changes what the order may leave behind. Kraken converts the held placement to immediate-or-cancel, meaning it can trade when released but cannot leave an unfilled remainder on the book. The original hold expiry stays the same.For example, a trader submits a non-post-only limit order and cancels before the hold expires. The cancel request bypasses the delay and converts the held placement to immediate-or-cancel. At the original...