These are the 5 most important execs who left Microsoft in 2019 — and 10 new power players who signed on

Harry Shum, the Microsoft executive charged with overseeing the artificial intelligence strategy for the entire company, is leaving after 23 years. He officially departs in February, but Microsoft confirmed the departure in November. 

Microsoft CEO Satya Nadella recently said artificial intelligence would play a key role in the company's future and central to the company's strategy to gain more customers for its important cloud business. Nadella said Microsoft is just now starting the "first innings" of artificial intelligence technology.

Shum was key to Microsoft's efforts to take the research it was doing through research subsidiary Microsoft Research and translate it to actual products Microsoft can sell. Now Microsoft has to do that without him just as the business is starting to come together.

Former LinkedIn Chief People Officer Christina Hall left the Microsoft-owned company in December.

Bloomberg reported Hall resigned after breaking internal compliance rules, citing "people familiar with the matter." The report didn't include specifics about the rules or what is said to have occurred.

Hall was responsible for human resources at LinkedIn, including hiring and benefits. Hall earlier this year told Business Insider her advice for managers and the one trait people need to get a job at LinkedIn.

Mike Ybarra, former corporate vice president of Microsoft's gaming division, left the company in November after nearly 20 years.

Ybarra was responsible for online video game multiplayer service Xbox Live, video game subscription service Xbox Game Pass and video game streaming platform Mixer.

Ybarra soon after joined Irvine, California-based video game developer Blizzard Entertainment as executive vice president and general manager.

James Boehm, co-founder of the video game streaming platform Mixer in 2016, left the company in October.

He joined Microsoft when Mixer was acquired and spent the next three years helping to deliver the service onto hundreds of millions of Windows 10 PCs and Xbox One consoles, according to the press release in which he announced his departure.

Boehm is now on the board of a company that designs lotions for gamers called Gamer Goo. The company's website says its products "stops sweaty and clammy hands at the source for up to four hours."

Microsoft's Corporate Vice President and Chief Marketing Officer of Xbox Mike Nichols retired in September after more than two decades with the company.

Jerret West, a former Netflix vice president and head of marketing who spent eight years at Microsoft in the early 2000s, was named as his replacement beginning in December.

Jacky Wright rejoined Microsoft in October with a promotion to chief digital officer.

Wright had left the company for two years to work for the British government's tax department, HMRC, as chief digital and information officer.

She was previously corporate vice president of Microsoft's core services engineering platform. 

"In her new role, Jacky will harness the technical intensity of Microsoft US to help accelerate our customers' ability to digitally transform," Microsoft said when it announced Wright's return.

Microsoft in August hired Apple's former Siri boss Bill Stasior as corporate vice president of technology in the office of Microsoft Chief Technology Officer Kevin Scott.

The Information reported Stasior will "help align technology strategies across the company" and lead an artificial intelligence group. Stasior left Apple in May.

Microsoft hired Google Cloud's former vice president of oil, gas, and energy Darryl Willis to oversee Microsoft's strategy for energy company customers.

Willis, now Microsoft's vice president of energy industry, spent nearly two decades combined at BP, most recently as president and general manager.

Microsoft in September nominated Emma Walmsley – CEO of drugmaker GlaxoSmithKline and the most powerful woman in Big Pharma – to the company's board.

The selection shows Microsoft has a growing interest in the health care space as the company targets the industry in sales for its cloud computing business.

Microsoft in April hired Greg Moore from his former post at Google Cloud to become the company's corporate vice president of health technology and alliances.

Moore was Google's top healthcare leader and reported directly to the Google Cloud CEO. 

Microsoft said Moore will be responsible for building partnerships with leading healthcare organizations to align their research with Microsoft's product development, a central part of the company's healthcare strategy.

Microsoft in September hired Bill Borden, a former managing director at Bank of American Merrill Lynch, as the company's new corporate vice president of financial services.

Borden leads Microsoft's global financial services strategy, which includes customers in banking, capital markets, and insurance. He is based in New York.

Microsoft hired David Rhew in August as the company's chief medical officer and vice president of healthcare.

Rhew joined Microsoft from Samsung, where he was chief medical officer, vice president and general manager for Samsung Electronics America's enterprise healthcare business.

Rhew is a medical doctor, but he's also a computer scientist who holds six U.S. patents including related to data in electronic health records.

Microsoft in August hired open source expert and former Red Hat manager Stormy Peters as director of Microsoft's open source programs office.

Microsoft was once a well-known opponent of open source technology, but made a big turnaround in the past few years under new CEO Satya Nadella. The company even acquired GitHub, the backbone of the open source community, in 2018.

Peters is a central character in Microsoft's open source strategy.

The world's most well-known video game streamer, Tyler "Ninja" Blevins, signed a deal in August to move from Amazon's Twitch platform to Microsoft's Mixer platform — a major coup for Microsoft.

As Business Insider's Ben Gilbert writes, the deal – the amount of which is undisclosed – allows Microsoft to lock in an important influencer who can both increase the value of Mixer and bring eyes to Microsoft's entire gaming platform.

Microsoft in November hired former US Attorney General Eric Holder to investigate an Israeli facial recognition company called AnyVision — in which Microsoft is an investor — and find out whether it complies with the Redmond-based company's ethical principles guiding its work with the technology.

News reports suggest AnyVision's technology is secretly used to monitor Palestinian residents in the West Bank. Holder will lead a team of former federal prosecutors at law firm Covington & Burling to investigate.

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