Empty description tag even though 'Show empty Metatags?' unchecked

In the default configuration for metatags, I kept Show empty Metatags? unchecked. I created a dynamic description metatag based on node.teaser. I enabled and inherited metatags for a content type, where body is optional.

When I generate a page for a node (my custom type) where there is no body, I get an empty description metatag(<meta name="description" content="" />).