diff --git a/src/caoscrawler/converters.py b/src/caoscrawler/converters.py
index 9b759d3c4a0674f8cd647d5b86be2ece7c19d9aa..728c308209e7e62f1b545e2a8348d59f08c5eac7 100644
--- a/src/caoscrawler/converters.py
+++ b/src/caoscrawler/converters.py
@@ -290,9 +290,10 @@ class Converter(object, metaclass=ABCMeta):
         self.name = name
 
         # Used to store usage information for debugging:
-        self.metadata: dict[str, set[str]] = {
-            "usage": set()
-        }
+        # TODO: remove?
+        # self.metadata: dict[str, set[str]] = {
+        #     "usage": set()
+        # }
 
         self.converters = []
 
diff --git a/src/caoscrawler/crawl.py b/src/caoscrawler/crawl.py
index 66a81c77605cd42f772ad7aa7d73c1b02c702d55..00363f9700914adaaa0b2b1c40074db2887983e9 100644
--- a/src/caoscrawler/crawl.py
+++ b/src/caoscrawler/crawl.py
@@ -4,8 +4,8 @@
 # ** header v3.0
 # This file is a part of the CaosDB Project.
 #
-# Copyright (C) 2021 Henrik tom Wörden
-#               2021 Alexander Schlemmer
+# Copyright (C) 2021 Henrik tom Wörden <h.tomwoerden@indiscale.com>
+#               2021 Alexander Schlemmer <alexander.schlemmer@ds.mpg.de>
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU Affero General Public License as
diff --git a/src/caoscrawler/structure_elements.py b/src/caoscrawler/structure_elements.py
index 952f29d012f8373062ed9dfe8a830bd18c4b0baa..c743d066d015c4401d90461dc549af1f94f21bc3 100644
--- a/src/caoscrawler/structure_elements.py
+++ b/src/caoscrawler/structure_elements.py
@@ -32,9 +32,10 @@ class StructureElement(object):
 
     def __init__(self, name):
         # Used to store usage information for debugging:
-        self.metadata: tDict[str, set[str]] = {
-            "usage": set()
-        }
+        # TODO: remove?
+        # self.metadata: tDict[str, set[str]] = {
+        #     "usage": set()
+        # }
 
         self.name = name
 
diff --git a/unittests/test_tool.py b/unittests/test_tool.py
index 187ec06e097a3aba1053c865eac1190654a267c0..12ea6fcacb696a933f1477fe9489744e5c66d024 100755
--- a/unittests/test_tool.py
+++ b/unittests/test_tool.py
@@ -3,7 +3,7 @@
 #
 # This file is a part of the CaosDB Project.
 #
-# Copyright (C) 2021 Alexander Schlemmer
+# Copyright (C) 2021 Alexander Schlemmer <alexander.schlemmer@ds.mpg.de>
 # Copyright (C) 2023 Henrik tom Wörden <h.tomwoerden@indiscale.com>
 # Copyright (C) 2023 IndiScale GmbH <info@indiscale.com>
 #