MacKenzie Bezos signs pledge to give at least half of her $36 billion fortune to charity

MacKenzie Bezos has become the latest billionaire to commit to giving at least half of their fortune to charity.

Bezos, whose net worth is estimated to be $36.6 billion, on Tuesday signed the Giving Pledge, a campaign launched by Bill and Melinda Gates and Warren Buffett that encourages the world's wealthiest people to give a majority of their wealth to charity during their lifetime or in their wills, CNN reports. In addition to Gates and Buffett, other past signatories have included Facebook CEO Mark Zuckerberg and Tesla CEO Elon Musk.

Her divorce settlement with Amazon CEO Jeff Bezos makes MacKenzie Bezos the fourth-richest woman in the world, Bloomberg reports, as well as the world's 22nd richest person. She is among the wealthiest people to sign the Giving Pledge so far. Jeff Bezos, the richest person in the world, has not signed it.

"I have a disproportionate amount of money to share," Bezos said on Tuesday. "My approach to philanthropy will continue to be thoughtful. It will take time and effort and care. But I won't wait. And I will keep at it until the safe is empty."

Among the other new signatories announced on Tuesday were WhatsApp Co-founder Brian Acton, whose net worth is reportedly $4 billion, and Pinterest Co-founder Paul Sciarra, whose net worth is $1.6 billion, Forbes reports. They were among the 19 people who signed the Giving Pledge on Tuesday, bringing its total number of signatories to 204.