(Reuters) – AT&T Inc (NYSE:) said on Tuesday it was selling its advertising unit, Xandr, to Microsoft (NASDAQ:), partly exiting a venture that had appeared to become expensive for the telecom company.

Xandr was established in 2018 by the acquisition of an ad-exchange and a TV adtech company. This allows you to target customers with data from TV, phone and internet services.

AT&T has spent billions to build a media company, satellite TV provider and an advertising platform all under one roof, but those plans faced investors’ criticism as struggled to reduce debt.

According to the telecom giant, its $43 billion merger of WarnerMedia and Discovery assets (NASDAQ:) Inc is set to be completed by 2022.

Microsoft is a major revenue generator through software licensing such as Windows or Office. However, it also operates advertising-supported businesses like its Bing search engine (or Bing), MSN news and LinkedIn business social networks.

“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,” said https://about.att.com/story/2021/xandr.html Mikhail Parakhin, President of Web Experiences at Microsoft.

This deal excludes the DirecTV advertising business and it is subject to regulatory review.

AT&T’s shares were up about 1.4% in early trading.