Health: Market Makers determine the bid ask. With low volume (which this stock is at, whether we are at 15k or 50k) its still low. The market makers (MMs) are the groups that have the effect on the bid/ask. If there was a high volume these investors/ firms would not have such control, it would simply move in the up direction with a buy predominance or downward with a sell predominance. MMs hold a large amount of stock and can establish the bid ask buy putting out large portions of shares for buy or sell. Sometimes I think that I own enough ASTV to do this myself, but since I don't want to sell at this level, I would rather not. hope that helps a bit.
Investopedia: 'Market Maker' A broker-dealer firm that accepts the risk of holding a certain number of shares of a particular security in order to facilitate trading in that security. Each market maker competes for customer order flow by displaying buy and sell quotations for a guaranteed number of shares. Once an order is received, the market maker immediately sells from its own inventory or seeks an offsetting order. This process takes place in mere seconds.
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