Say for example, you want to buy at the ASK price of $0.0001; the market maker will fill the trade at $0.00005 or whatever they chose to sell at. This has happened to me plenty of times. Good Luck!
A new trade reporting facility opened November 17, 2014 - FINRA set it up strictly for OTC stocks after eliminating the OTCBB - this new facility shows all six digits. However, placing orders is still limited to the minimum of $.0001 by FINRA for the OTC.
The trades that you see at 5 to 6 digits are either after arbitrage or an occasional market order transaction.
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