Saudi Arabia was home to 10 billionaires last year, according to Forbes. This year, it has none.
Forbes said it was unable to assess the wealth of the oil kingdom's richest men after a corruption probe late last year that left many of them detained for months in a 5-star hotel.
Some were later released after agreeing to hand over cash and other assets worth more than $100 billion, but Saudi officials have given few details about individual settlements.
"There are a thousand and one stories about what precisely happened, making it impossible to know definitively who gave how much to whom when," Forbes said on its website.
"Given these shifting sands of truth, we've chosen to leave all ten Saudis off our billionaires list this year; none would comment," it added.
The most prominent figure arrested last year was Prince Alwaleed bin Talal, a global investor with stakes in Citigroup (C), Twitter (TWTR) and Apple (AAPL). In the 2017 Forbes list, his net worth was pegged at $18.7 billion.
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The prince spent nearly three months at the Ritz-Carlton hotel in Riyadh before he was freed in January. Shares in his company, Kingdom Holding, gained more than $1 billion in value on news of his release.
It remains unclear whether Prince Alwaleed's personal fortune is intact, however, because the conditions of his release have not been made public.
He has fallen out with Forbes in the past, suing the magazine for libel in 2013 after it said he was worth only $20 billion. They agreed to settle the case in 2015.
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Since the crackdown on corruption, officials have been trying to assure international investors that their country is open for business. The Saudi government is hoping to encourage investors to commit cash in support of its economic transformation program, Vision 2030.
Crown Prince Mohammed bin Salman, who is spearheading efforts to wean Saudi Arabia off oil, is in London this week before he heads to the US later this month.
