diff --git a/synapse/handlers/profile.py b/synapse/handlers/profile.py
index 834b37f5f3dc9e4aaf5be6cc815c3a62cb0c3a92..7853bf5098dbf47971ca3753a6551d14f32fd636 100644
--- a/synapse/handlers/profile.py
+++ b/synapse/handlers/profile.py
@@ -202,7 +202,6 @@ class ProfileHandler(BaseHandler):
 
             content = {
                 "membership": j.content["membership"],
-                "prev": j.content["membership"],
             }
 
             yield self.distributor.fire(
diff --git a/synapse/handlers/room.py b/synapse/handlers/room.py
index d09743ed1b841745a496ee903fbe94cd1c6b1a4d..7d9458e1d00dae36d0fc7eefa1cf9c7826a8b0a0 100644
--- a/synapse/handlers/room.py
+++ b/synapse/handlers/room.py
@@ -364,9 +364,6 @@ class RoomMemberHandler(BaseHandler):
             target_user_id, event.room_id
         )
 
-        if prev_state:
-            event.content["prev"] = prev_state.membership
-
         room_id = event.room_id
 
         # If we're trying to join a room then we have to do this differently