Specialists can see the stop orders. Market makers should be aware of the order flows (including stop orders) of their books. Market makers also have the access to Nasdaq level III. General people have the access to Level I or Level II. It's possible a market maker can benefit by delays the orders. I do not know how long can a market maker legally delay the orders. Does any one how long can a market maker legally delay the orders?
I found only this definition for Level III: >>Level III This quote platform is restricted to Nasdaq member firms who are registered Market Makers and to a number of large brokerage firms. It provides all of the Level II data but, in addition, gives Market Makers the ability to enter or change quotes, execute orders, and send out confirmations of trades. >> Essentially which is the edge vs. the Level II?
You could say that with Level III Nasdaq build itself a lill' 'trading pit' for their buddies. Why else should level III be kept away from public view?