What's an ad?
We all know what happens when we click on the following news item:

It's a Bloomberg article, so what else can we expect but a paywall?

Today, it dawned on me, and I don't know why it took so long, that the news item above is an "ad"!
It's advertising Bloomberg subscriptions.
But there is no "ad" symbol.
The advertising industry has created a category called "native ads." This is when a news item is labeled "sponsored", "promoted", etc. For example:

But the Bloomberg item is not considered a native ad, even though the primary purpose of the item is to drive subscriptions.