Amazon's Jeff Bezos has surpassed Bill Gates to become the world's richest man Thursday.

Assuming stock gains, Bezos has executed a meteoric rise up the billionaires list a testament to the growing might and wealth of the Seattle company he runs.

Microsoft co-founder Gates, 61, has held the top place in the billionaire list since May of 2013. Just a year ago Bezos was number five on the list.

But on Thursday their places look likely to change.

After the market opened Thursday, Amazon shares rose more than 1% driving Bezos' net worth to $90.9 billion, compared to Gates' $90.7 billion. Gates was worth $90.8 billion while Bezos was at $89.9 million, according to the Bloomberg Billionaire Index.

Amazon (AMZN) shares surged Thursday morning, in anticipation of the company's earning statement expected after the bell. Early on in the day they hit $1,074.68.

Should those gains hold throughout the day, Gates could cede his long-held place to Bezos, 53.

Unlike many of the world’s richest people, Bezos has not signed the Giving Pledge, a campaign launched in 2010 by Warren Buffett and Gates to encourage the world’s wealthiest people to contribute the majority of their money to philanthropic efforts.

More than 150 have done so, including many in the tech elite including Larry Ellison, Mark Zuckerberg and his wife Priscilla Chan, and Elon Musk.

He maintains a web site listing some of his philanthropic investments at Bezos Expeditions.

In June, Bezos did ask his Twitter followers for suggestions on what he could do to make the world a better place.

"This tweet is a request for ideas," he wrote in the tweet June 15. "I'm thinking of a philanthropy strategy that is the opposite of how I mostly spend my time — working on the long term."

Some of those projects he cited in his tweet included Blue Origin, the aerospace manufacturer and spaceflight services company he founded, and the Washington Post, which are "contributing to society and civilization in their own ways," he wrote.

So far, Bezos has not announced what short-term projects might come out of his tweet. He did not respond to a request for comment.