This has been going on for years. It’s not surprising. When I was on the trading floor, those orders were called good till close, then it’s cancelled. The specialist at one point could freeze the book and the order could not cancel, unfortunately the sec disallowed freezing the order. Now the orders pop in and out. Technology sometimes gets abused, we are stuck with it.
How much can this really effect the market at any time?
Can this cause wild fluctuations? or is it more just aggregate?
It’s almost like a game to these hedge funds. The market went down last week and up this week. The news is the same. While they are playing, they put phony orders on the book to shake out sellers or buyers. There is no policing by the sec. It’s a sad state.