Additional Windchill Capabilities > Manufacturing Process Management > Transforming an eBOM into an mBOM > Cutting and Pasting Equivalent Occurrences
  
Cutting and Pasting Equivalent Occurrences
When cutting a part with equivalent occurrence links from the structure tree and pasting it into a different location, equivalent occurrences are maintained provided that the new downstream location has an equivalent upstream link. Additionally, positioning information is maintained.
If the part that is cut has more than one equivalent occurrence link then the occurrence link is duplicated.
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After pasting the copied part at its new location, you must select View > Update Equivalent Occurrence Status from the structure toolbar to populate the part’s occurrence status column.
To enable equivalent occurrences, the Equivalent Occurrence Links preference in the Preference Management utility must be set to Yes.