In order to offer a fair and equitable marketplace, we’ve built rules into our order matching engine that will be helpful for you to understand.
Orders that are routed to the exchange are prioritized first by price and then by time. The buy side priority is highest price first, followed by the oldest order. The sell side priority is lowest price first, followed by the oldest order. Market orders take priority over limit orders. If an order is cancelled and then placed again, it is sent to the back of the line. This means that priority is given to the order and not to the trader.