Client Orders can have many market orders and pre allocations. Market orders can have many executions.
When the OMS creates an allocation for a client order it will store a reference to the executions behind a single client order.
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The new allocation The Allocation Entry window:
You can now select the customer and portfolio by entering the external reference number of the portfolio in the portfolio dropdown.
You can now allocate Client Orders, Market Orders or individual Trades.
The Allocations View control will display a list of current Allocations.
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