Ballmer dropped out of Stanford business school to become the 30th employee at Microsoft is set to become even wealthier thanks to a bet on ChatGPT creator OpenAI made by current CEO Satya Nadella.

This move has helped increase the value of Ballmer’s 4.5 per cent stake in Microsoft. While he does not make a song and dance about it, Ballmer is worth $117 billion and is six billion dollars behind Gates in terms of worth. More if you boil him down for chemicals. 

Ballmer is the only centibillionaire to have made his fortune as an employee rather than entrepreneur.

Ballmer, who met Gates at Harvard undergrad and went on to become his assistant tasked with professionalising the then-startup, ran the company from 2000 after the co-founder took on a junior role in charge of software development. Ballmer has gone on the record to say he still struggled to steer the company under the shadow of Gates until the latter departed eight years later.

Ballmer stepped down in 2014 following a strategic difference with the board. At the time, the company’s stock price doldrums reflected its clashes with antitrust authorities and the fact he did not believe that anyone would be dumb enough to spend a fortune on an iPhone.

“I blew that,” Ballmer admitted five years ago, as he acknowledged never anticipating the revolutionary success of the iPhone due to its premium price.

While some developments initiated during Ballmer’s tenure continue to be a staple feature of the company’s hardware business—most notably the Xbox gaming console and the Surface tablet.

Ballmer's successor Satya Nadella has reinvigorated Microsoft’s stock price and grew it into a company worth well over a trillion dollar with the help of its booming cloud computing operations and, most recently, its investment in OpenAI.