Microsoft said Wednesday that top security leader Charlie Bell will take on a new role and that Hayete Gallot will return to the company to run security after a stint at Google.

Bell joined Microsoft in 2021 after 23 years at Amazon, where he played a key management role inside Amazon Web Services. He’s moving into a position focused on engineering quality as an individual contributor, or IC, continuing to report to CEO Satya Nadella.

“Charlie and I have been planning this transition for some time, given his desire to move from being an org leader to being an IC engineer,” Nadella wrote in a memo to employees. “And I love how energized he is to practice this craft here day in and day out!”

The changes comes as investors worry that generative artificial intelligence models might damage the growth prospects of mature software companies. On Tuesday, Microsoft announced that four sales executives were becoming executive vice presidents, in a move the company said was meant to improve its ability to stay close to clients while pursuing growth in AI.

Microsoft shares are down 14% this year, and the iShares Expanded Tech-Software Sector ETF has declined about 21%. In Microsoft’s earnings report last week, the growth rate for Azure was weaker than some analysts expected.

Gallot arrived at Microsoft in 2009, taking a role in strategy and business development. When she departed for Google’s cloud unit to be president of customer experience in 2024, she was a corporate vice president working on selling products in a variety of categories, including security, according to her LinkedIn profile.

“She brings an ethos that combines product building with value realization for customers, which is critical right now,” Nadella wrote.

In her new role, Gallot will be an executive vice president reporting to Nadella. Ales Holecek, chief technology officer for Microsoft’s Experiences and Devices Group that includes the Windows operating system and other products, will become chief architect for security and will report to Gallot, Nadella wrote. 

During Bell’s tenure, Microsoft had to deal with the fallout from prominent cyberattacks. In 2023, Microsoft said China breached U.S. government officials’ email accounts, leading to a critical Department of Homeland Security report. Microsoft made operational changes and started evaluating cybersecurity contributions in employee reviews that influence compensation.

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