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YouTube is still the king of Internet video, but AOL's takeover of Adap.tv last month is making it the richest in that kingdom.

In ComScore's Web video rankings for September, AOL topped Google as the property with the most video ads watched last month, with 3.7 billion views compared to the YouTube parent's 3.2 billion.

It was in September that AOL closed its takeover of Adap.tv, a company that automates the marketplace of video ads. The $405 million takeover was the largest for Chief Executive Tim Armstrong since he took command of AOL, eclipsing the purchase of Huffington Post.

AOL's move to the No. 1 spot is largely a benefit of simply adding in AOL's ad numbers to Adap.tv's, which was the No. 2 property the month before.

"Clearly this is early. What they reflect right now is the sum of parts, but it's where the parts are growing quickly," Amir Ashkenazi, CEO and founder of Adap.tv, told CNET. "So I do think what you should expect is even faster growth."

In addition, according to AOL, its 3.7 billion ads were the largest number by a single property ever recorded by ComScore.. And looking at the previous month's stats shows the move to No. 1 has more to it than only arithmetic. Had AOL and Adap.tv been counted together in August, their total would have still fallen short of Google.

The news comes one month after AOL overtook Facebook in the ComScore ranking of Web properties' unique video views. Google is still the leader in that category by far, but AOL's climb reflects Armstrong's focus on video as the home of the fastest-growing ad market on the Web.

The online media company has also enlisted A-list celebrities like Sarah Jessica Parker, Gwyneth Paltrow, and Jonathan Adler to either host or star in original Web series for its AOL On Network, the company's video platform.

Last week, AOL sealed a partnership with ESPN to syndicate clips from the coveted sports network on AOL Web sites, including owned sites like Huffington Post, and onto connected devices through its AOL On app.