TradeStation Help
The Underlying Asset/Existing Position window is where you enter one or more Underlying Assets to change. If you do not know the symbol for the underlying asset, you can press the Lookup button, which will bring up a dialog that will allow you to find the symbols you wish to consider. Underlying Stock and Index symbols are the only valid symbol that search can analyze, do not enter specific option root symbols.
You will be able to make your selections from all the available optionable stock and index symbols. When you select the underlying asset(s), the Search automatically links each underlying asset with all its corresponding options based on your proximity settings for strike and expiration date.
You may select more than one underlying asset on which to search. For example, if three stocks are listed, the search will include the options of all three stocks. By selecting multiple assets, you may compare one asset's option positions with another.