***Update*** We began writing and researching this article in the middle of last week. Then out of nowhere, Amazon crushed their third quarter earnings and the stock exploded. With the explosion, Jeff Bezos' net worth increased $10 billion in 48 hours. And with that jump, he ended up snagging the title of richest person in the world from Bill Gates. He topped Bill's net worth by $1 billion. Bill's net worth ALSO increased a few billion last week thanks to strong Microsoft earnings, but not enough to keep his crown. Sooooo the answer to the article below is… he already lost it!
Bill Gates has been the richest person in the world for 18 of the past 23 years, but his reign is close to coming to an end. Amazon's Jeff Bezos is nipping at Gates' heels with a net worth just $1 billion short of Gates' $90 billion. Of course, Gates could and would be much richer if he wasn't a founder of the Giving Pledge, which stipulates that members must donate at least half of their fortunes in their lifetimes. But he is and Amazon's soaring stock is about to put Bezos in the top spot, possibly indefinitely.
We estimate that Gates would be worth about $150 billion if he hadn't already donated $2.6 billion in cash and assets and nearly 700 million shares of Microsoft to various causes and philanthropies. Warren Buffett is in the same situation. He has spent the past 10 years donating shares of his Berkshire Hathaway to charity. He has a current net worth of $75 billion. If he hadn't been so charitable, he'd have about $135 billion today.

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Earlier this summer Jeff Bezos passed Bill Gates to become the richest person in the world for a few hours when Amazon stock soared. By the end of the day, the share price had fallen some and he fell back into his role as the second richest person in the world. He is just starting to get his footing as a major philanthropist. At 53, he has a ways to go to catch up to 61-year-old Gates and 87-year-old Buffett. You may remember how Bezos sent a tweet out to ask the public how and where he should contribute to philanthropy. Bezos has been donating shares of Amazon since 2002. Those shares total around $400 million at current share prices. Bezos also sells $1 billion worth of his Amazon shares each year to fund his pet project—his space exploration company Blue Origin.
Gates and Buffett have both done most of their giving through the Bill & Melinda Gates Foundation. The foundation focuses on improving issues like health care and poverty across the globe. The foundation has made $41 billion in grants and has assets worth $40.3 billion. Gates and Buffett founded the Giving Pledge in 2010. Since that time, 168 fellow billionaires have committed to give most of their wealth away.
Jeff Bezos isn't the only billionaire threatening Gates' hold on the title of the richest man in the world. Zara founded Amancio Ortega's $80 billion net worth is only $10 billion behind Gates.
How long do you think it will take for Jeff Bezos to claim the title of the richest person in the world?
(Answer: A lot less time than we predicted when we thought of this article idea!)