Amazon's founder Jeff Bezos was briefly the world's richest man today when Amazon's share price surged just ahead of the company's quarterly results.
When they peaked at $1,083.31, Bezos was worth $92.3 billion, which put him ahead of Bill Gates's $90.8 billion fortune. Bloomberg promptly reported: Jeff Bezos Surpasses Bill Gates as World's Richest Person.
However, Bezos slipped behind Gates when the share price retreated about four hours later, and he's now worth only $89.3 billion.
Gates has generally been the world's richest man for decades, thanks to the value of his share of Microsoft. He has been overtaken from time to time -- once by Oracle's Larry Ellison -- but never put under sustained pressure.
However, it's reasonably safe to predict that Gates will finally hand over the poisoned chalice to his fellow Seattle billionaire.
There are two reasons to think this will happen. First, Gates has spent the past decade being a philanthropist, and he's already given away $31 billion. If he hadn't, Bezos wouldn't even be close. Second, Gates isn't benefiting from Microsoft's booming stock price, because he's no longer a major shareholder. Even Steve Ballmer owns more shares than Bill.
How long Bezos might keep the top spot is much harder to judge.
Bezos's rise to riches has been short and sharp, and the result of the rapid rise in the value of Amazon shares. According to CNBC, Bezos's "net worth has grown by $70 billion over the past five years, surging by $45 billion in the last two years alone -- possibly the largest wealth-creation surge in history."
A decade ago, Bezos was only worth $4.4 billion.
A bear might suggest that Amazon is a bubble stock and that its share price isn't justified by the company's sales and profits. A market "correction" would see Bezos plunge down Bloomberg's Billionaires Index.
A bull would note that Amazon only operates in a small number of countries, that it still doesn't carry a full range of products, and that there are still lots of retail sales for Amazon to cannibalize.
Amazon still has enormous growth potential inside the USA. It has enormous growth potential in China and India, where it is a relative newcomer. It has enormous growth potential in more than 180 countries where it doesn't have local subsidiaries. These include Spain and Portugal, all the Nordic countries (Norway, Sweden, Denmark, Finland), all of South America except Brazil, plus all of Eastern Europe, the Middle East and Africa.
If Bezos stumbles, then Facebook founder Mark Zuckerberg could take the top spot. His net worth has grown by $22.5 billion in the past year to $72.5 billion. (Mind you, it fell by $2 billion today.)
Given the stunning performance of Alphabet/Google, Larry Page ($47.5 billion) and Sergey Brin ($46.4 billion) are also tips for the top.
They're just outside the Top 10 at the moment, but as Bezos's example shows, things can change dramatically in technology.