1 files changed, 8 insertions, 4 deletions
diff --git a/rrd/models.py b/rrd/models.py
index 2dc629a..7ccc89a 100644
--- a/rrd/models.py
+++ b/rrd/models.py
@@ -23,19 +23,23 @@ def _sanitize_path(path):
 class ModelWithPerms(models.Model):
     users_read = models.ManyToManyField(
         amodels.User,
-        related_name="%(class)s_read"
+        related_name="%(class)s_read",
+        blank=True,
     )
     users_write = models.ManyToManyField(
         amodels.User,
-        related_name="%(class)s_write"
+        related_name="%(class)s_write",
+        blank=True,
     )
     groups_read = models.ManyToManyField(
         amodels.Group,
-        related_name="%(class)s_read"
+        related_name="%(class)s_read",
+        blank=True,
     )
     groups_write = models.ManyToManyField(
         amodels.Group,
-        related_name="%(class)s_write"
+        related_name="%(class)s_write",
+        blank=True,
     )
 
     class Meta: