Can you please give me a few names of market data providers that have the real-time list of stocks that are halted on NYSE (I'm specifically interested in pre-open, both news pending and imbalance). For example, I know that AT financial's list of most active NYSE listed stocks will mention all the halts. Sorry if this question has already been discussed, I'm doing a search on ET right now.
I asked the Nyse about 18 months ago about order imbalances before the close and they said they were going to do an email service. Try sending them an email