From FIXwiki

FIX Message Component OrderQtyData

The OrderQtyData component block contains the fields commonly used for indicating the amount or quantity of an order. Note that when this component block is marked as "required" in a message either one of these three fields must be used to identify the amount: OrderQty, CashOrderQty or OrderPercent (in the case of CIV).

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Notes

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For example if you were writing a clarification on how to specify the "quantity" of an order in FIX, you might add the
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