This could be all or none order usually gets filled at close, if any one is trying to sell a large order it get filled at close. This is very common. You can see bid is .057 and the offer is .0572 yet it gets filled at .0527 I have already given the reason how it happened.
it looked like the trade could have been in the morning spike as it was a large trade 550k and was in a big up move candle, good buy for someone though
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