I think the only way @TradeViper s solution wouldl be right is if all these big players were doing this is to hit sell @ market to drive the price down, then hit Buy at market and pull th eprice up again and rely on selling at better prices than the buy back.
I’m really not convinced that would work and if it did, within the vast lumps of money, why not reverse the system when price was rising to benefit from the underlying market movement. This is not happening.
A further notable “coincidence” is that every one of those tails starts at an exact pip value and most seem to be at 2 pips behind the real bar (ie price ends in a zero) There is one exception, a little doji bar in the minute following 20:20. Wicks on the upside do not show this, they are pretty random and just end where they end. I cannot believe that any trading resource would cause this “Zero effect”, but why it should occur due to a computer recording system either - I don’t know !
BUT those long tails and the zeros plus my previous experience on the DOW Futures leads me to believe the “Glitch” more than the “Computer trading” theory.
I do hope someone can come up with a reason why such a “Glitch” cannot be cured ?
And I’m still open to the Computer trading argument if someone can explain how and why that would work and make money.