Microsoft is buying the Xandr Inc. ad marketplace from AT&T for an undisclosed amount. The two companies announced the deal via an AT&T press release on December 21. 

Xandr is a "first-tier affiliate" of AT&T, according to the press release, as well as a "data-enabled technology platform powering a global marketplace for premium advertising. Xandr offers ad products including Xandr Invest, Xandr Monetize, Xandr Curate and Invest TV. The release says Xandr's technology complements Microsoft's current ad offerings, including its audience intelligence, technology and global advertising customer base.

Microsoft's own ad-buying solution, the Microsoft Audience Network, its PromoteIQ retail-media solutions and Microsoft Customer Experience Platform for marketers is the backbone of Microsoft's digital advertising platform.

Microsoft is continuing to look for ways to expand its digital advertising business. Its Web Experiences Team (WebXT) is focused on using Edge, Bing and Microsoft Start (the renamed MSN News) to grow Microsoft's advertising business. During the last few months, Microsoft has been adding more shopping features to its Edge browser. It also has been working on getting more users to click on Microsoft Start content by including it in a widgets panel in Windows 11.

As part of its Q1 FY22 earnings report, Microsoft officials said search and news advertising revenue, excluding traffic-acquisition costs, was up 40% compared to the year-ago quarter, citing both a low prior-year comparable and improved customer advertising spend as drivers.

Updates: Bloomberg (citing unnamed sources) says Microsoft paid$1 billion. Meanwhile, back in July, Axios reported AT&T was in discussions to sell Xandr to Indian ad-tech vendor InMobi. At that time, Axios said Xandr was losing "tens of millions a year and has been grossly mismanaged by AT&T."

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