If you have a FIX request, notifications of changes and comments go out to the person who sent the request, the person who accepted the request and, if the activity is to pick up or drop off a person, a notification will also be sent to the person that is to be picked up or dropped off. If there is a change, or someone writes a comment, before anyone has been able to accept the FIX request, the notification goes out to anyone who has not rejected the request. 


If you have a SYNC request, notifications of changes and comments go to the person who created the activity and to all persons that will participate in the activity.