Here is why all the manipulation. You really do need to read up on these ECN's. They can trade any way they like.
Electronic Communication Network - ECN
An electronic system that attempts to eliminate the role of a third party in the execution of orders entered by an exchange market maker or an over-the-counter market maker, and permits such orders to be entirely or partly executed.
Investopedia explains Electronic Communication Network - ECN An ECN connects major brokerages and individual traders so that they can trade directly between themselves without having to go through a middleman.
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