Microsoft chief executive Steve Ballmer, the world's 44th-richest person, has seen his net worth jump $786 million (R8 billion) since announcing his retirement from the largest software maker.
The 57-year-old is the second-largest individual shareholder of Microsoft, after co-founder and chairman Bill Gates, the world's richest man. Ballmer's net worth is $16.8bn, according to the Bloomberg Billionaires Index. On Friday he said he planned to step down within the next 12 months after serving as chief executive since 2000.
"Investors want new leadership to navigate the company in a world that doesn't rely on the PC anymore," said Jack Ablin, the chief investment officer of BMO Private Bank in Chicago. "In a big picture sense, he's done a good job."
Microsoft rose 7.3 percent to $34.75 at the close of trading in New York on Friday. The stock has gained 30.1 percent this year, driving up Gates's fortune by 15.4 percent and Ballmer's by 21.5 percent.
Gates co-founded Microsoft with billionaire Paul Allen in 1975, and is still its largest individual shareholder with a 4.8 percent stake.
Ballmer, who joined Microsoft in 1980, holds 4 percent. Allen, who controlled as much as 28 percent of Microsoft's shares, now holds 2 percent, according to the index.
The world's richest man derives about 19 percent of his $72.4bn fortune from Microsoft shares and saw his net worth increase by $1.1bn on Friday.
Almost 70 percent of Ballmer's fortune is derived from Microsoft shares. The rest of his fortune stems from stock and dividends.
Allen left Microsoft in 1983 before beginning his career as a media, technology and sports team investor. He has about 25 percent of his $15.4bn fortune tied to Microsoft shares, which added $251m.
Microsoft has lost almost half its value under Ballmer's leadership and the shares have not closed above $50 since his first year on the job.
Ballmer attended Harvard University with Gates. Unlike his schoolmate, who left the Ivy League institution before graduating, he stayed and received a bachelor's degree in applied mathematics and economics.
Before joining Microsoft he worked as a marketing executive for Procter & Gamble, the world's largest consumer goods producer.
Since taking over the chief executive role from Gates, Ballmer has been working to bolster Microsoft's performance in areas like mobile computing and away from the PCs that have long been powered by Microsoft's flagship Windows software.
Last month, he presided over the biggest reorganisation of Microsoft in a decade in a bid to speed up development of hardware and services as the company's Windows business suffers from the shrinking PC market and poor demand for Windows-based mobile devices.
"This is a time of important transformation for Microsoft," Ballmer said in his resignation announcement. "This is an emotional and difficult thing for me to do. I take this step in the best interests of the company I love."
He planned to remain one of the company's largest owners. He has the fifth-largest stake. - Bloomberg