diff --git a/app/models/metadata_has_and_belongs_to_many.rb b/app/models/metadata_has_and_belongs_to_many.rb
index 905000ee..e08c9917 100644
--- a/app/models/metadata_has_and_belongs_to_many.rb
+++ b/app/models/metadata_has_and_belongs_to_many.rb
@@ -76,6 +76,8 @@ class MetadataHasAndBelongsToMany < MetadataBelongsTo
   end
 
   def post_exists?
+    return true if empty? && can_be_empty?
+
     !belongs_to.empty?
   end