diff --git a/app/models/custom_field.rb b/app/models/custom_field.rb
index b7861808b015..19b625c91d7a 100644
--- a/app/models/custom_field.rb
+++ b/app/models/custom_field.rb
@@ -281,13 +281,11 @@ def boolean?
   end
 
   def multi_value_possible?
-    %w[version user list].include?(field_format) &&
-      [ProjectCustomField, WorkPackageCustomField, TimeEntryCustomField, VersionCustomField].include?(self.class)
+    %w[version user list].include?(field_format)
   end
 
   def allow_non_open_versions_possible?
-    version? &&
-      [ProjectCustomField, WorkPackageCustomField, TimeEntryCustomField, VersionCustomField].include?(self.class)
+    version?
   end
 
   ##