In the history of sudden wealth loss, Li Hejun may have set a new record.
Li, who was China's richest man until this week, saw his fortune drop by as much as $15 billion in a half-hour as the stock in his company, Hanergy Thin Film Power Group, fell by nearly half. Trading in the shares was halted Wednesday and Li didn't attend the company's annual meeting. (Tweet This)
While plenty of billionaires have seen their fortunes cut in half over time, few if any have seen $15 billion wiped out in a half-hour. Li's total fortune was around $30 billion before the stock plunged.
Prior to the drop, the company's shares had risen by more than fivefold since September, baffling analysts. Reuters reports that .
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In a similar wealth decline, Hong Kong property and electronics magnate Pan Sutong has lost more than $11 billion this week as shares of two listed companies, Goldin Financial and Goldin Property, both closed down more than 40 percent.
Pan owns around 65 percent of Goldin Property and more than 70 percent of Goldin Financial, according to filings. His fortune was listed at more than $28 billion, making him Hong Kong's second-richest man.
That means that the two men have lost more in one day that the total net worth of Carl Icahn, Steve Ballmer or Michael Dell.
Pan is known for his large lifestyle. He's a big polo supporter and has sponsored a polo event in Britain attended by Princes William and Harry. He's said that the sport "is a way of life and belief in a sense of nobility."
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Pan also owns vineyards around the world, including three in France and one in California's Napa Valley, called the Sloan Estate, which he purchased in 2011 for around $40 million.