It means 200 share MM signals being sold. Not sure if I believe that theory but if you watch L2 you'll see the tiny share whacks and 5 digit prints which are usually MM trades.
MM's have signals between themselves 200 means I Need Shares Badley, Do Not Take The Price Down. GOOGLE: MM SIGNALS 200 and you will see all their signals listed
News 
Market Data 
Discover 
AI
