That distinction likely goes to the House of Saud, the ruling royal family of Saudi Arabia. Comprising 15,000 family members (although a majority of the wealth is only held by about 2,000 of them), the House of Saud is estimated to be worth $1.4 trillion. For reference, that's nearly 16 times the British royal family's net worth.
Much like their British counterparts, the members of the Saudi royal family are notoriously private about their fortune. But what is known, suggests an envious lifestyle filled with big spending, private jets, luxury yachts, top of the line helicopters, sprawling chateaus and a palatial estate decked out with gold furniture — including a gold-plated Kleenex dispenser.
However, members of the family also provide money to those in need through charitable organizations and invest in the Saudi people. More recently, the country pledged millions to a World Bank fund for female entrepreneurs.
Origin of the the family wealth
Their riches stem from the vast oil reserves uncovered more than 75 years ago, under the reign of King Abdulaziz ibn Saud. The country's state-owned natural gas and petroleum company Saudi Aramco is valued by some at more than $2 trillion. If that estimation is correct, it would be one of the world's most profitable oil companies.
The leader of the pack
One of the most influential members of the royal family is King Salman of Saudi Arabia, who succeeded his late brother Abdullah bin Abdulaziz Al Saud in 2015. Reportedly worth $17 billion, the 82-year-old has handed over much of the country's leadership to his son and heir to the throne Crown Prince Mohammed Bin Salman, 32.
The future of the royal family
In an effort to clamp down on corruption last year, the crown prince forced the country's richest people to turn over their fortunes to the state, including many of his own relatives. As a result, Forbes dropped ten Saudis from its annual list of the world's billionaires.
The country claims to have recouped more than $100 billion through this "corruption campaign," but that figure is impossible to verify.
The finer things
According to the New York Times, the heir recently purchased a a $450 million Da Vinci painting, a $500 million yacht and a $300 million French chateau. He reportedly also owns two homes in London and a compound on Spain's southern coast.
In an interview with CBS News, the Crown Prince said that his finances were a private matter and that he did not need to apologize for an opulent lifestyle. "I'm a rich person and not a poor person. I'm not Gandhi or [Nelson] Mandela," he said. "I'm a member of the ruling family that existed for hundreds of years before the founding of Saudi Arabia."
He also claimed that a large share of his wealth goes toward charity. "I spend at least 51 percent on people and 49 on myself," said the prince.
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