Dentsu Aegis Network has kept its grip on Microsoft's mammoth media agency business.

Ad Age first reported the news of the review in December, when the tech giant said it was conducting a closed review of its media account as part of its "normal course of business." Adweek reported the winner earlier Friday.

The tech giant awarded the work to Dentsu, with the win led by media agency Carat. Dentsu and Carat deferred comment to the client.

"After completing a review of our global media agencies, we are extending our relationship with Dentsu Aegis," Kathleen Hall, corporate VP of brand, advertising and research at Microsoft, said in an emailed statement.

In April 2014, Microsoft selected Interpublic Group as agency of record for advertising and global deployment and Dentsu Aegis Network to handle search advertising and media buying and planning — right on the heels of appointing Chris Capossela as its new chief marketing officer.

The Redmond, Washington-based tech company continues to work with m:united//McCann, a dedicated agency within IPG, for its creative work.

The tech giant said last summer it would be overhauling its sales and marketing organization, reportedly cutting 3,000 to 4,000 jobs, to "better serve [its] customers and partners."

The Ad Age Datacenter estimates Microsoft Corp. spent an estimated $1 billion in worldwide measured media for calendar year 2016. The company stated that its worldwide "advertising expense" for fiscal year (ending June 30, 2017) was $1.5 billion.

Dentsu Aegis Network won media and creative work for Subway across North America in December. The network was also a big winner in Anheuser-Busch InBev's global media agency review last fall, with Vizeum taking over media planning and buying in the U.S., Canada, Europe and Africa.