diff --git a/src/c3nav/editor/forms.py b/src/c3nav/editor/forms.py
index 0f873bca..2123f75d 100644
--- a/src/c3nav/editor/forms.py
+++ b/src/c3nav/editor/forms.py
@@ -48,6 +48,8 @@ class EditorFormBase(I18nModelFormMixin, ModelForm):
             sources = {s['name']: s for s in Source.objects.all().values('name', 'access_restriction_id',
                                                                          'left', 'bottom', 'right', 'top')}
             used_names = set(sources.keys())
+            if not creating:
+                used_names.remove(self.instance.name)
             all_names = set(os.listdir(settings.SOURCES_ROOT))
             self.fields['name'].widget = Select(choices=tuple((s, s) for s in sorted(all_names-used_names)))