How does a broker know you are (consistent) profitable ?

This question is crucial for any FX broker to know whether you should be A-booked or B-booked as trader. But how do they know this when to hedge their position to other counterparties ? What kind of trading statistics you need therefore ? What do you think or assume here ? When do you know as trader you get A-booked instead of B-Booked (more slippage or anything else ?) on a FX broker ? Let me know your thoughts and insights please.

 

It is the transaction that is usually A-booked or B-booked. There might be exceptions.

 

I know, but how do you know this as trader ? When does a broker decide on what criterias to do this ?

 

With exception the trader is not automatically booked A or B.

 

So broker knows where FX market will go?
Or they are simply keeping their books in balance?

 

When it becomes statistically unlikely that you consistently produce certain positive returns. They gather data across their client base and when you fall like in 5 or 1 percentile of the best traders they can start to hedge your trades