Use mass ownership change when you need to transfer one user's data to another user This applies to cases where, for example, a colleague is leaving and their records need to be handed over to someone else. The change takes just a few clicks and can only be performed by an Administrator.
Click on the Settings button in the top right corner under your name.
From the left menu, select the Mass Ownership Change option.
Choose the original and new owner and check the items for which you want to perform the mass change. If you are using security levels, set the appropriate level as well. Finally, click the Change Owner button.
The change will reflect on all selected records, except for those already completed or canceled activities. Those will remain under the ownership of the original user, so you won't lose information about who actually completed the activity.