Believe me, you don't want to hear who they are. They are bad news but often move off the ask especially when the sp is moving up fast. They're dilutors of the stock and nobody likes them hanging around.
Not dumb at all. As Marilyn said, they are what are referred to as MM's (Market Makers). MM's are the group that all trades go thru into the market including when you and I buy/sell stocks. The ones you mentioned are many times known for diluting shares for the company/selling them into the market.
List of the Money-Makers. Here is a list of the people who like to steal our money. VFIN is usually bad for dilution but, have seen them disappear in a hurry in a run. They also buy and sell so it can be hard to tell.
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