AT&T has agreed to sell its global programmatic advertising marketplace, Xandr, to Microsoft. The agreement builds on a decade-long relationship between Xandr, including its predecessor companies, and Microsoft for delivering global digital media solutions for advertisers.

AT&T said that  Xandr’s technology strategically complements Microsoft’s current advertising offerings and will help accelerate delivery of digital advertising and retail media solutions for the open web by combining Microsoft’s audience intelligence, technology and global advertising customer-base with Xandr’s scaled, data-driven platform.

“Microsoft’s shared vision of empowering a free and open web and championing an open industry alternative via a global advertising marketplace makes it a great fit for Xandr,” said Xandr’s EVP and GM, Mike Welch. “We look forward to using our innovative platform to help accelerate Microsoft’s digital advertising and retail media capabilities.”

For Microsoft, Mikhail Parakhin, President of Web Experiences, said: “With Xandr’s talent and technology, Microsoft can accelerate the delivery of its digital advertising and retail media solutions, shaping tomorrow’s digital ad marketplace into one that respects consumer privacy preferences, understands publishers’ relationships with consumers and helps advertisers meet their goals.”