CurrentUserGroups and SharePoint 2013 Task List

I'm in a SharePoint 2013 environment. I have the following filter in a task list: 
"<Where><Or><Membership Type="CurrentUserGroups"><FieldRef Name="AssignedTo"/></Membership><Eq><FieldRef Name="AssignedTo"/><Value Type="Integer"><UserID Type="Integer"/></Value></Eq></Or></Where>"
How do I get this so that it shows the tasks affiliated with the Groups that the current user is a member of? The results I am getting are only the tasks that the user is personally assigned. I feel like I'm missing something really simple and it's driving me batty.
<o:p></o:p>

JFitch