They have history with that check finra website it's would make millions and pay 1 or 2 millions as fine why not hahah
Is SPY not traded on a dozen different venues, as opposed to futures listed on only one exchange? It is likely the low would be different on ARCA and different elsewhere.
I reply to myself - there is a provision called Rule 611 of Reg NMS that says: "The core of Rule 611 is paragraph (a)(1), which promotes intermarket price protection of orders by restricting the execution of trades on one venue at prices that are inferior to displayed quotations at another venue." So the low should be the same across all venues, in theory.