Who is CSE and why aren't they in TWS (IB)?

I see a market maker with the letters CSE in Level II, posting large size in several stocks, but this size never shows up in IB TWS...wondering why not?

(Yes, CSE is at the best bid/ask, but nevertheless, their size still does not show in TWS: only in my level II quotes that I'm getting through someone else....)

 

CSE is a regional exchange and IB doesn't route to regionals.

 

I have them as well as the Amex direct connection. Only the few and proud have access to them while it lasts.


Jeff--