From 32trades.com
Why Are Market Makers Important?
Like it or not, your fate is in the hands of market makers since they essentially control the stock market. Your order placed to buy or sell a stock on the OTC Markets will usually pass through one of the more trusted sources like NITE, ATDF, ETRF, and ARCA. Seeing a level 2 screen which only has these on it is what’s referred to as a “Clean Level 2” – one with no dirty hands on it. Typically, these four are there to do what markets makers are supposed to do which is simply fill buy & sell orders without attempting to manipulate the behaviour pattern of a particular stock.