Today, we're launching a beta test for expandable rich media ad units on the Google content network. This ad format can expand to double the original size of the ad to provide more information to your audience about your product. Expandable ads can also include a streaming video or other content designed to engage users through an interactive experience.

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Expandable ads on the Google content network are designed to automatically expand in the direction where the most space is available on the screen. They must be clicked by the user to expand and contract. These features help create a positive experience for users and provide you with more accurate ad engagement metrics by avoiding expansions triggered by accidental mouse-overs. Expandable ads can also help AdSense publishers by engaging users on their sites with more ad variety and opportunities to interact with the ad content.

For now, expandable ads will be available as a limited beta test in the U.S. to advertisers and agencies participating in our 3rd Party Ad Serving program. Please stay tuned for future updates as we expand this test.