diff --git a/builtins/amp-ad.md b/builtins/amp-ad.md
index f6e143294c1a..23ce48221d4d 100644
--- a/builtins/amp-ad.md
+++ b/builtins/amp-ad.md
@@ -1,13 +1,10 @@
-### `amp-ad`
+## `amp-ad`
-NOTE: The specification of `amp-ad` is likely to significantly evolve over time. The current approach is designed to bootstrap the format to be able to show ads.
+**Note:** The specification of `amp-ad` is likely to significantly evolve over time. The current approach is designed to bootstrap the format to be able to show ads.
A container to display an ad.
-Ads are loaded like all other resources in AMP documents, with a special
-custom element called ``. No ad network provided JavaScript is allowed to run inside the AMP document. Instead the AMP runtime loads an iframe from a
-different origin (via iframe sandbox) as the AMP document and executes the ad
-network’s JS inside that iframe sandbox.
+Ads are loaded like all other resources in AMP documents, with a special custom element called ``. No ad network is required, provided that JavaScript is allowed to run inside the AMP document. Instead, the AMP runtime loads an iframe from a different origin (via an iframe sandbox) as the AMP document, and executes the ad network’s JS inside that iframe sandbox.