AT&T to Sell Xandr Advertising Business to Microsoft

AT&T acquired the advertising platform AppNexus in 2018 for $1.6 billion, and relaunched it as Xandr (named after Alexander Graham Bell) the next month. The goal at the time was to leverage AT&T’s first-party phone data with Xandr’s advertising technology and WarnerMedia’s content to create an advertising business that could rival that of Google or Facebook.