For the uneducated who do not understand trading and how a company can dump 10 billion shares and go to no bid.
What market makers do.
Market makers must maintain continuous two-sided quotes (bid and ask) within a predefined spread. A market is created when the designated market maker quotes bids and offers over a period of time. They ensure there is a buyer for every sell order and a seller for every buy order at any time.
Once the market maker has entered a price, he or she is obligated to either buy or sell at least 1,000 securities at that advertised price. Once the market maker has either bought or sold these shares, he or she may then "leave the market" and enter a new bid or ask price to make a profit on the previous trade.
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