Right now BMAK is the top bid at .0070 and also the top ask at .0072. If anyone wants to buy, they have to bid at least .0070 or their order is blocked by BMAK. If anyone wants to sell, they have to sell at .0072 or less or be blocked by BMAK, thus BMAK controls the pps. The second BMAK drops its bid, the other brokers follow suit. When BMAK raises the ask, the brokers follow suit. Throughout most of the day BMAK sets the minimum bid and the maximum ask, for this past week anyway.
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