I didn't have a chance to check POLA during the day, but what appears to have happened is that someone slowly and very methodically ratcheted up the bid. When 200 shares were sold to test the bid, then buyer slapped back with a 200 share buy at the ask.
Almost looks as though someone was doing both sides of these transactions. Really a fascinating chart. Not sure at all what it portends. Hopefully the fundamentals will come through and blow all of these minor technical considerations out of the water.
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