Less than two months after finalizing her divorce from the world’s richest person, MacKenzie Bezos has indicated that she intends to be a far more generous philanthropist than her husband has been.

MacKenzie Bezos announced in a letter on Tuesday that she had signed the Giving Pledge, a commitment to give half of her $35 billion in assets, or at least $17 billion, to charity over her lifetime or in her will. Despite facing criticism for being the world’s richest man but having donated only a tiny fraction of his wealth, Bezos’s ex-husband, Amazon founder Jeff Bezos, has for years conspicuously declined to sign on.

MacKenzie’s commitment to the Giving Pledge comes as liberals are accusing companies like Amazon of being anti-competitive and are questioning more loudly than ever whether CEOs should be able to accumulate fortunes in the tens of billions of dollars in the first place, which shows how times have changed.

Nine years ago, the Giving Pledge and its chief ambassadors, Bill Gates and Warren Buffett, were heralded as today’s Andrew Carnegie and John D. Rockefeller, at the vanguard of a new movement by American billionaires to remake global philanthropy by encouraging earlier, bigger, and more public giving. Since then, tech billionaires in particular have had to begin playing defense on their philanthropic efforts — especially since some see these gifts as PR cover for their capitalist misdeeds. And a headline-capturing, vague philanthropic commitment like the Giving Pledge is particularly susceptible to scrutiny because it is only a promise, with plenty of wiggle room and zero accountability.

That’s especially true in Silicon Valley, where some rival groups to the Giving Pledge are increasingly gaining traction, as Recode reported last month. While the Giving Pledge can claim to be ultimately responsible for more than $500 billion in commitments, other philanthropic efforts like Founders Pledge — focused on earlier-stage tech entrepreneurs — and Pledge 1%, focused on corporate giving, are hoping to replicate and disrupt the Giving Pledge, forcing it to compete for the mindshare of today’s tech community.

Representatives from the Giving Pledge have told Recode that they felt it was performing well within the tech community, and the 18 new signers it announced on Tuesday are a reminder of the pledge’s dominance. Joining MacKenzie in signing the pledge on Tuesday were Twilio founder Jeff Lawson and his wife Erica; venture capitalist Chris Sacca and his wife Crystal; and Brian Acton, the WhatsApp founder who now encourages people to delete Facebook after selling it his company for $19 billion, along with his wife Tegan.

These new additions bring the total number of Giving Pledge signers to more than 200 people — which sounds like a lot until you realize that’s only about 7 percent of the world’s billionaires. Many of the world’s wealthiest people who call Silicon Valley home, such as Sergey Brin and Larry Page, have not signed.

Jeff Bezos hasn’t signed it either, although he’s not immune to pressure to become more philanthropic. After becoming the world’s richest man in 2018, Bezos announced last year that he would commit $2 billion to early education and anti-homelessness programs. As Amazon faces high-stakes questions about its power and threats of governmental regulation, Bezos seemingly realized he could no longer afford to entirely ignore his critics.

And that’s what makes MacKenzie Bezos’s decision so revealing. The Bezoses had nine years to sign the Giving Pledge and declined to do so over and over again. But as soon as MacKenzie Bezos was in charge of her personal fortune, she immediately signed the document. That obviously raises questions about whether she disagreed with her husband about their philanthropic strategy.

If she did, she gave no signs of it in her letter announcing her plans, dated this past Saturday, May 25, just before the Giving Pledge’s annual retreat takes place this week. And yet she intimated that she stood by the idea about charitable giving that her ex-husband has long expressed: You shouldn’t rush into it.

“We each come by the gifts we have to offer by an infinite series of influences and lucky breaks we can never fully understand. In addition to whatever assets life has nurtured in me, I have a disproportionate amount of money to share,” MacKenzie Bezos said in her letter. “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.”

The letter didn’t offer many specifics, so how exactly MacKenzie Bezos, a novelist, will fulfill her philanthropic commitment has yet to be seen. She has said as part of the divorce process that she and Jeff Bezos would continue their joint philanthropic work on homelessness and early education. So far, she has focused most of her public attention on anti-bullying efforts, which could perhaps become a major focus of her philanthropic work.

As one of the world’s wealthiest women, she will be under the microscope. But like Jeff Bezos, she has until now tried to remain a private figure, rarely weighing in publicly on Amazon matters despite her key early role at the company, for instance.

Their divorce, the costliest split in the history of divorces, suddenly thrust MacKenzie Bezos into countless headlines. And her decision to sign the Giving Pledge, which by its public nature was bound to attract attention and questions, is an indication that she — also like Jeff Bezos — is increasingly leaning into that spotlight.

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