When the account linked to the source of a post has been suspended, deactivated, or deleted. Note that while this tag has a large overlap with bad id, some platforms may keep posts from deleted or deactivated accounts accessible.
For Twitter, this can be detected if a post link shows the message: "This Post is from a suspended account".
For Tumblr, this can be seen in the blog's URL, as it will have -deactivated appended to the end of the URL, followed by the date of deactivation.
