diff --git a/api/utils/serializer/serializer.py b/api/utils/serializer/serializer.py
index c8e9083..3820b30 100644
--- a/api/utils/serializer/serializer.py
+++ b/api/utils/serializer/serializer.py
@@ -133,4 +133,19 @@ class AbstractModelAPISerializer:
         return self.model.objects.get(
             id=id,
             users__in=[user]
-        )
\ No newline at end of file
+        )
+
+    @abstractmethod
+    def initialize_objects(self, json_model, user):
+        """ Initializes all needed objects from the json_model data
+
+        Does not persist data to the DB!
+
+        Args:
+            json_model (dict): The json data
+            user (User): The API user
+
+        Returns:
+            obj (Intervention)
+        """
+        raise NotImplementedError("Must be implemented in subclasses")
diff --git a/api/utils/serializer/v1/compensation.py b/api/utils/serializer/v1/compensation.py
index d06807e..3cc2261 100644
--- a/api/utils/serializer/v1/compensation.py
+++ b/api/utils/serializer/v1/compensation.py
@@ -81,8 +81,10 @@ class CompensationAPISerializerV1(AbstractModelAPISerializerV1):
         """
         intervention = Intervention.objects.get(
             id=intervention_id,
-            users__in=[user],
         )
+        is_shared = intervention.is_shared_with(user)
+        if not is_shared:
+            raise PermissionError("Intervention not shared with user")
         obj.intervention = intervention
         return obj