IMO, your discount brokerage company is a uninterested in trading in penny stocks. They make next to nothing as it is on a regular trade if they are charging you less than $10. With that in mind, they actually lose money on penny stock trades because there is a cost per share to actually trade stocks which is usually covered by the commission unless you are trading massive amounts of shares. So if they can find a reason to stop trading pennies, they will.
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