You are ridiculous no retail can trade past 4 decimal places. If you think that is incorrect go to whatever platform you trade from and give it a go. It will display a error message that states you are not able to trade in fractions past 4. The trade of 500 to the 5th decimal may have been MMS chopping up a order and using it to how they see fit but 0 retail investors entered in a sell to 5 decimal places for 500 shares
That is not proof ... proof is try to physically put in a limit order with your brokerage for anything past the 4th decimal digit on your electronic device ... YOU CAN’T ... even if you call your broker asking them to do it ... YOU CAN’T ... say you put your limit at the 4th decimal but it does get filled at the 5th or past ... that is not retail filling it even though you may or may not have got it for that. The MMs are the ones who designated for it to be filled at that. As well they have the ability to break up the order to get filled how they want while fulfilling it. Whether it be 500 ... 911 ... or even 1. Retail has no control.
Back last year when Float was locked I slapped the ASK very hard. MMs could not fill my order. Kept getting MULTIPLE fills at 100 trades then pps jumped up past my limit so I had to set it higher. I was also getting trade jumped. MMs do what they want. I called and complained to my broker and their hands were tied saying the MM fills the order and I would just have to increase my limit. I was pissed and if I recall I even submitted a complaint to the SEC.
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