3.1.4.3.2.2 Additional Constraints for the Tasks Folder

If a delegate is to process task requests on behalf of the delegator, a client MUST:

1. Grant send on behalf permission to the delegate.

2. Grant, to the delegate, the Author or Editor role on the delegator's Task special folder, as specified in [MS-OXCPERM] section 3.1.4.2. Note that granting the Author role will allow the delegate to act only on new items and on items that the delegate creates.