[projektfu]

As you're learning about the story, you might hear a few things "on background, off the record." That means that you can't really act like you were told that, but you now know that you have a story. So, you start reporting, and over time you get employees asking for anonymity from 10 hospitals to say such and such, and from 12 hospitals to say another thing, and you heard some of this on background. So you can say "at least" but you can't say the full number. If there is a libel or defamation lawsuit, your sources can be reviewed under seal, but since you don't note the source of your background information, you can't state that those sources exist.