diff --git a/backend/composer/api/permissions.py b/backend/composer/api/permissions.py
index e0a06841..b74891a1 100644
--- a/backend/composer/api/permissions.py
+++ b/backend/composer/api/permissions.py
@@ -25,8 +25,8 @@ def has_permission(self, request, view):
         if request.method in permissions.SAFE_METHODS:
             return True
 
-        # Checks if creator is the owner of the related entity (if related entity exists)
-        if request.method == 'POST':
+        # If creating a new instance, ensure related entity ownership
+        if request.method == 'POST' and view.action == 'create':
             return check_related_entity_ownership(request)
 
         # For unsafe methods (PATCH, PUT, DELETE), allow only authenticated users
@@ -59,25 +59,6 @@ def has_object_permission(self, request, view, obj):
         return obj.connectivity_statement.owner == request.user
     
 
-class IsSentenceOrStatementOwnerOrSystemUserOrReadOnly(permissions.BasePermission):
-    """
-    Custom permission to allow:
-    - System user to bypass all checks.
-    - Only the owner of a sentence or connectivity statement can create a note.
-    """
-
-    def has_permission(self, request, view):
-        # Allow system user to bypass all checks
-        if request.user.username == 'system' and request.user.is_staff:
-            return True
-
-        # Allow read-only access (GET, HEAD, OPTIONS)
-        if request.method in permissions.SAFE_METHODS:
-            return True
-
-        # For POST (create), PUT, PATCH (update), or DELETE, check ownership
-        return check_related_entity_ownership(request)
-
 
 def check_related_entity_ownership(request):
     """
diff --git a/backend/composer/api/views.py b/backend/composer/api/views.py
index f48c8951..c6406eb2 100644
--- a/backend/composer/api/views.py
+++ b/backend/composer/api/views.py
@@ -45,7 +45,6 @@
     BaseConnectivityStatementSerializer,
 )
 from .permissions import (
-    IsSentenceOrStatementOwnerOrSystemUserOrReadOnly,
     IsStaffUserIfExportedStateInConnectivityStatement,
     IsOwnerOrAssignOwnerOrCreateOrReadOnly,
     IsOwnerOfConnectivityStatementOrReadOnly,
@@ -321,7 +320,9 @@ class NoteViewSet(viewsets.ModelViewSet):
 
     queryset = Note.objects.all()
     serializer_class = NoteSerializer
-    permission_classes = []
+    permission_classes = [
+                permissions.IsAuthenticatedOrReadOnly,
+    ]
     filterset_class = NoteFilter