No it is not, 100% of the trades can be marked short. You have failed to understand how trades are marked and transacted in the OTC market.
Mary has a limit offer for 1000 shares at 1$ Joe puts in a bid for 1000 shares at 1$
The market maker Sells Joe 1000 shares for 1$ which is the first leg of the trade and is a short sale. SO THE WHOLE TRADE IS MARKED AS SHORT. Then the second leg is transacted and the market maker then buys 1000 shares from Mary. So now they both have their shares and money switched and the MM is flat.