Changing the File Owner
To change the owner of the file, display the file detail page and click Edit. On the Edit File page, first make sure that the file is shared with whomever you want to make the owner the file, and then check the Owner radio button next to the person that you want to make the owner of the file and click Save.
If you pass ownership of a file to another network member, the new owner of the file receives a notification of the ownership change in their activity stream. If the new owner has checked the Shares content with me directly setting on the Follow & Activity Settings page, they also receive an email notification.
If you are a network administrator and change the ownership of someone else’s file, then both the original owner of the file and the new owner receive notifications as described above. Note that in this case, the original owner of the file retains the ability to edit the file, they simply no longer are the file owner.