Enterprise tasking allows a user in Practice A to send a task to a user in Practice B. To enable this feature you need to update your Clinical tasking preferences.

To do that open the Inbox in EHR, then click on the "gear"

Click on the "Preferences" option to open the tasking preferences.

Uncheck the "Task List by Enterprise \ Practice"

If there are many tasks, you can control the filter by "hiding" tasks older to the minimum which is one month.