Click the Copy Down Task from the Asset Form, Task Window, to open the Copy Down Form:
Click a field in the list to select it for Copy Down. To select more fields hold down the Ctrl Key and click each additional item until all the required fields have been selected.
Click the Copy button.
Things to be aware of:
•Copy Down will propagate the data in one or more fields of an Asset, to the same fields in all of its descendants
•Copy Down is independent of Attribute Sets, so take care that User Fields being copied do not conflict with the intended purpose of User Fields in descendant Assets with a different Attribute Set