Facebook and Meta founder Zuckerberg saw his net worth slashed by more than half.
The Silicon Valley tech titan now sits 17th on the index with a total of $86 billion, after he lost $95 billion in the first six months of the year.
Musk’s fortune plunged almost $90 billion, while Bezos’ wealth tumbled by $92 billion.
Both entrepreneurs, however, remain firmly at the top of the billionaires index.
Tesla founder Musk is now worth $310 billion, according to the index, while Amazon boss Bezos has a personal fortune of $195 billion.
While Rinehart is very much top of the Australian wealth tree, she slides down to 76th richest person in the world, the rankings estimate.
Musk’s company Tesla has endured a particularly difficult start to the year.
The electric car company faces billions of dollars in losses from its new plants, supply chain problems and COVID-19 lockdowns, Musk revealed in an interview last month.
“The past two years have been an absolute nightmare of supply chain interruptions, one thing after another,” Musk said.
“We’re not out of it yet.
“That’s overwhelmingly our concern is how do we keep the factories operating so we can pay people and not go bankrupt.”
All seven tech entrepreneurs who dominate the top-10 Bloomberg index have seen their net worth drop this year.