Why was my order rejected with "Error 503"?

When you see the message "No opening trades: ineligible PINK stock" it means an opening order for that contract is not allowed, even if your account has trading permissions for US Penny Stocks.

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This error message will appear in the Order Preview window when submitting a short sale order after the order goes through a credit check and it is determined that IBKR will not be able to borrow shares by the trade settlement date.

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If you do not have sufficient funds to cover the Initial margin requirements for a futures contract order, the following will occur:

1. Order Rejection: Your order will be automatically rejected by our system.
2. Error Message: You will receive an error message on your trading platform…

The IBKR API is not available to IBKR Lite accounts. If you are logged into an IBKR Lite account through an API, when you submit an order you will be given an error message "You are not allowed to trade on IBKR-LITE account."

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