OCTX is connected to OTCMarkets, which maintains the markets : OTCQX, OTCQB and Pink. It seems odd to me they can also buy/sell in those markets, like the SEC having its own market maker. Anyway, mostly high frequency trading, they will aggressively out bid or out ask your order, and mostly flip shares from what I have seen of them. Anything sold to them on the bid, gets put immediately back on the ask at whatever price their algo predict the price will hit. But people that use InteractiveBrokers for a broker have told me their orders route through OCTX sometimes, so they can be retail at times.