KUALA LUMPUR (Sept 22): South Korean Kim Jung-youn is the world's youngest billionaire, according to Forbes.

In a report on Wednesday (Sept 21), the magazine said that while both Jung-youn, 18, and her elder sister Kim Jung-min inherited equal shares of a 30.78% stake each in South Korea-based NXC, the teenager has now become the world’s youngest billionaire.

NXC is the largest shareholder in Japan-listed Nexon, with a nearly 48% stake.

The duo are the daughters of Kim Jung-ju, the South Korean founder of Nexon who died in February at the age of 54.

Forbes said that together with the sisters’ existing shares in NXC, their stakes in the company are worth US$2.5 billion each.

After deducting their inheritance tax bill, which Forbes calculates at over US$1.5 billion each (South Korea has one of the highest inheritance taxes in the world), Jung-youn’s and Jung-min’s net worths are estimated at US$1 billion each.

Jung-ju’s wife, Yoo Jung-hyun, who was already a billionaire, inherited a 4.57% stake in NXC from her husband.

Forbes said Yoo, 53, helped Jung-ju start Nexon in 1994 and remains the largest shareholder in NXC with a 34% stake.

It said she made her debut on Korea's 50 Richest list this year with a net worth of US$3 billion.

The magazine said that before his death, Jung-ju was ranked the third-richest person in South Korea last year, right after pharmaceutical tycoon Seo Jung-jin and Samsung’s Jay Y Lee, with a net worth of US$10.9 billion.