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The Google-Facebook duopoly dominating the digital ad market is about to get company.

Amazon is expected to pull in $40 billion in annual ad revenue by 2023, new research shows, up from miniscule levels just a few years ago. According to recent report from Juniper Research, the e-commerce giant’s ad business will grow more than 470% over the next five years, outpacing the growth rates of both Google and Facebook in that period, and making it one of Amazon’s fastest-growing and most profitable business segments.

Amazon has been expanding its offerings to advertisers over the years, selling inventory across its sprawling website to niche products like the Chefman pressure cooker and, more recently, to well-known household brands from Unilever and Procter & Gamble. Display ads, paid search results, and instructive videos are just some of the available inventory.

Amazon doesn’t disclose its digital ad revenues publicly, but analysts have a good beat on its progress as it makes up an overwhelming chunk of a line item that the company calls “other.” Using that measure, Amazon’s digital ad revenues topped $2.7 billion in the first quarter of 2019. That was a mild disappointment, but the segment looks like a promising financial driver as the company’s core retail business begins to grow at a slower clip.

On the first quarter earnings call with analysts in April, Amazon chief financial officer Brian Olsavsky lumped the ad business in with Amazon Web Services’ cloud business as one of the company’s fastest growing segments with particularly strong demand from marketers in North America and Europe.

Amazon’s momentum in ads is happening at an inflection point for online marketing. Growth rates for digital ads, industry wide, are beginning to slow, Juniper and others say. Earlier this month, prominent venture capitalist Mary Meeker, in her closely-read annual Internet Trends report, noted that the companies that can harness the data they collect about users to send increasingly targeted ads—particularly for e-commerce—will emerge victorious in this highly competitive space.

Amazon has been investing heavily in machine learning and the data mining of its customer’s browsing and buying tendencies to deliver more sophisticated ad targeting. That’s catching on with advertisers, says Sam Barker, the report’s author. “In turn, advertisers will churn from Google and Facebook’s ad platforms” to Amazon’s.

Amazon did not immediately respond to a request for further comment about its ad business.

In the study, Juniper Research shares a five-year horizon that suggests the increased investment in A.I. will impact advertisers’ return on ad spending over the next two years. Juniper also warns of a consumer and regulatory backlash ensuing over the sheer collection of personal data.

These factors will lead to a greater shakeout among digital ad platforms. The tech companies that can most reliably deliver targeted ads will distance themselves from the pack. “The most successful platforms will be those which have access to, and can successfully leverage the largest datasets,” Barker says.

By 2023, the global digital advertising market will hit $520 billion, up from $294 billion this year. At that point, the top three digital advertising platforms—Google (at $230 billion), Facebook ($110 billion) and Amazon ($40 billion)—will comprise roughly three-quarters of the market, according to Juniper Research.

In research from earlier this month, Meeker showed that revenue from Amazon’s ad business was growing nearly twice as fast as Google’s. To wit, Juniper Research predicts Google’s share of the global digital ad market will dip by a single percentage point to 44% by 2023, while Amazon’s marketshare will grow from 3% today to 8% of the worldwide digital ad market in 2023.

From Peanuts to $40 Billion, Amazon’s Ad Business Set to Be the Next Great Disruptor

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