The distinction between spoofing and market making is very clear.  When a market maker puts an order on both sides of the market the would absolutely <i>love</i> it if both orders traded.  That is, in fact, how they make money.  In general they would love every single order they put in to trade, so long as it happens in the right order.<p>When a spoofer puts in a spoofed order, that order is all cost.  Under no scenario do they want that order to trade.  The hard distinction to make in this case is not between normal market making behavior and spoofing, but between normal hedging behavior and spoofing.  Hedges look like pure costs, but they are costs you are happy to pay to give up some risk.  So spoofing all comes down to intent, which seems pretty easy to prove when you have chat transcripts.<p>Whether spoofing <i>should</i> be illegal is another discussion, and probably one the legislature should have, but for now while it is illegal, it should be aggressively enforced as if it&#x27;s not, it incentivizes the bad actors.