Steve Ballmer is now worth $157 billion — more than his former Microsoft boss Bill Gates

Bill Gates and Steve Ballmer. Elaine Thompson/AP

• Bill Gates' former assistant is now wealthier than his old boss for the first time.
• Steve Ballmer, who succeeded Gates as Microsoft CEO, is worth an estimated $157 billion.
• Microsoft stock has surged amid a broader AI boom, boosting Ballmer's net worth.

A former assistant to Bill Gates has scaled the ranks of the world's wealthiest people to become richer than his old boss for the first time.

Steve Ballmer's fortune more than doubled from $77 billion in November 2022 to $157.2 billion at Monday's close, putting him sixth on the Bloomberg Billionaires Index.

Gates, Microsoft's legendary cofounder and perhaps the world's best-known philanthropist, is in seventh place and worth $156.7 billion. He was $17 billion richer than Ballmer a year ago.

Ballmer is now about $5 billion behind Alphabet cofounder Larry Page, who is in fifth place on Bloomberg's rich list at ($162 billion).

The Los Angeles Clippers basketball team owner, Ballmer ranks above the likes of Oracle's Larry Ellison ($156 billion), Alphabet's Sergey Brin ($153 billion), Warren Buffett ($128 billion), Michael Dell ($116 billion), and Nvidia CEO Jensen Huang ($109 billion).

Steve Ballmer owns the Los Angeles Clippers. Thomson Reuters

Ballmer owes his wealth to joining Microsoft in 1980 as an assistant to the president — a role more akin to a business manager than a PA. He originally agreed a $50,000 base salary plus 10% of the profit growth he generated. But Ballmer's compensation soon became outsized, so he agreed to exchange it for a significant equity stake, according to Forbes.

A close advisor to Gates, he succeeded him as CEO in 2000. Ballmer stepped down in 2014 with 333 million shares, or a 4% stake, regulatory filings show.

Bloomberg's estimate of Ballmer's wealth assumes that he's retained most of his Microsoft shares. The outlet values his stake at more than $150 billion based on Monday's $457 closing price — over nine times its split-adjusted level in 2014 when Ballmer left. He's likely to have collected dividends worth billions of dollars over the years as well.

Ballmer's net worth has skyrocketed over the past 18 months or so because of the artificial-intelligence boom, which Microsoft has tapped into by investing in industry star OpenAI. The stock has jumped by over a third in the past year alone.

Gates has fallen behind Ballmer because he's diversified his personal investment portfolio away from Microsoft stock, and made large donations to his foundation and other charities.

Even so, it's striking that Ballmer is officially richer than Gates, given how rare it is for an employee to become wealthier than his company's founder.

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