I think it's a matter of what the SEC allows MMs to do for these crappy tickers to allow them to even keep trading. After all, if the ticker gets delisted by Finra, the shares they pick up at the 5th and 6th digit are worthless. And if people want to take the tax loss, the only buyer is an MM since no one is interested in buying at $.0001.
Do you actually see quotes at $.00001 or $.000001 anywhere?
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