Can the free delayed market data feed from IBKR be used with Ninja Trader?

No. Delayed market data is available from recent versions of the TWS API, but is incompatible with NinjaTrader specifically because the functionality required to request and display delayed data has not been implemented within the NinjaTrader platform. To receive data from IBKR in NinjaTrader, it's necessary to have market data subscriptions enabled in the Client Portal.

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