Prompted by Butterfly's excellent thread 'IB API HOWTOs and Guidelines - For Beginners', I want to understand better what limitations (if any) prevent NinjaTrader (NT) from being used for automated trading in a situation where market access is DIRECT rather than through a brokerage firm. For autotrading, three functional components must be present (thank you, Butterfly!): (1) Trading logic execution (2) Market data feeds (3) Trade execution NT handles â1â, ... ... the NT data connection partners usually handle â2â, and â3â is handled by the NT brokerage partners. - I am not aware of NT being used for Direct Market Access, i.e. for connecting directly to an exchange without routing through a brokerage firm or data connection partner (so "2" and "3" provided directly by the exchange). Is anyone aware of any instances where in fact it IS used this way? - If not, why not? Is the reason as simple as being that no-one has yet attempted to write the required client/message server architecture (thanks again, Butterfly!) to connect NT with an exchangeâs price and order servers? Most exchanges seem to provide FIX protocol connectivity as at least one of the connection options, so connecting NT with such exchanges should be technically unchallenging. Or is there another reason why it is not done? Thanks.