Using Ideate BIMLink for Revit, checking Include Linked Elements checkbox will make two changes to your exported data. First, it will include all elements, as defined by the link, that also exist within any linked Revit file. Secondly, it will alter the value in the Id column to support this method. The new value in the Id column will be formatted as such:
<Unique Id of the linked Revit file>:<Element Id>
Some properties are not supported yet across linked files - refer to the Known BIMLink Issues section for more information.
To learn how to import this linked file data, see Import Linked File Data via BIMLink for more information on this feature.
Learn about reporting spatial data across linked files in BIMLink.
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