The "Official site" badge is a snippet of text shown next to the advertiser's display name. The following image shows the badge:
When official site badges show
Google displays the badge for hotel owners, direct suppliers, central reservation systems (CRS), and integration partners (IPs). The badge won't appear for online travel agencies (OTAs).
Only one partner for hotel ads and free booking links will receive an official site badge. If a hotel owner doesn't want a CRS or IP to ever show this badge, they must reach out to the third-party advertiser to stop sending rates, inventory and, if applicable, stop bidding on the property. There's no cost to add official site badges to your campaign. Clicks on your ad are charged as usual, and you're charged a click when someone clicks any element of your ad.
When there's more than one price feed for the official site
Google automatically picks the best available hotel rate for your hotel based on feed quality considerations such as price accuracy as well as comprehensive and competitive rates. Google dynamically picks the best available rate for your hotel per user.