Jeff Bezos’ former wife, known as world’s 22nd richest person with $36.6bn fortune, signs up to the Giving Pledge

MacKenzie Bezos, who recently became the world’s fourth richest woman after her divorce from Jeff Bezos, founder and chief executive of Amazon, has promised to give away at least half her $36.6bn (£28.4bn) fortune.

The 49 year-old novelist and founder of the anti-bullying group Bystander Revolution said on Tuesday that she had “a disproportionate amount of money to share” and promised to work hard at giving it away “until the safe is empty”.