The List Cancel Request <K> message type is used by institutions wishing to cancel previously submitted lists either before or during execution.
After the list has been staged with the broker, it can be canceled via the submission of the List Cancel message. If the list
has not yet been submitted for execution, the List Cancel message will instruct the broker not to execute it, if the list
is being executed, the List Cancel message should trigger the broker's system to generate cancel requests for the remaining
quantities of each order within the list. Individual orders within the list can be canceled via the Order Cancel Request <F> message.