In an email to advertisers, the Google-owned platform said the change follows its move last year to retire all full-day masthead ads, like the one then-President Donald Trump used on Election Day 2020. Such ads it said would be replaced with more targeted ads that are bought on a per-impression basis, meaning it would be more difficult for one advertiser to dominate YouTube’s homepage.

The unit involves a banner running across the top of the video platform’s homepage, and, according to the company, is the most prominent Google advertising placement available to advertisers.

The change is effective immediately, with gambling now listed as one of YouTube’s Prohibited Categories for its masthead ad: “Assets that depict or reference gambling-related content, including offline gambling, online gambling, online non-casino games, and social casino games.”

“We believe this update will build on changes we made last year to the masthead reservation process and will lead to a better experience for users,” a Google spokesperson told Axios, who first reported the story.

Ads that endorse a candidate for office meanwhile will be banned, as well as ads that promote the sale of alcohol.