She emigrated when she was 14, married his much older grandfather, and raised hogs in an impoverished part of Kyushu, the third largest of the islands that make up Japan. As a child, Son was happy to ride around on a wheelbarrow filled with scraps for the pigs.
His family's circumstances improved over the years, shifting from raising hogs to running a restaurant, but Son began to feel ashamed of his Korean background as he grew older and even rejected his grandmother. He took on a Japanese name.
It was not until his decision to attend high school in the U.S. at age 16 that he vowed to become an entrepreneur, seeing it as a way to create a more inclusive world, he said at the end of his two-hour presentation, fighting tears.
Against that backdrop, Son triumphantly declared Monday that with the Sprint deal his company had truly beaten Nippon Telegraph and Telephone Corp., a former government monopoly and an iconic symbol of old Japan, and was on its way, he hoped, to No. 1 mobile company in the world. The combination of Softbank and Sprint will be the world's No. 3 mobile company by revenue.
In Japan, Softbank was always an also-ran third to NTT DoCoMo, NTT's mobile unit, and KDDI Corp. That began to change after Softbank worked out a deal with Apple, thanks to Son's American connections, to be the first to offer the iPhone in Japan where the market was dominated by cellphones compatible only with the country's special network-linking formats.
Softbank users in Japan have grown to more than 30 million from 19 million in 2008, the year it began offering the iPhone. KDDI began offering the iPhone only last year. NTT DoCoMo recently acknowledged it won't offer the iPhone.
Analysts anticipate an even bigger exodus to Softbank with the ongoing rollout of the iPhone 5, potentially catapulting Softbank to No. 1 in Japanese market share in coming months.
"Some people have been waiting four years for DoCoMo to come out with an iPhone. They're fed up with waiting," said Hisashi Kamio, a consultant, who has written books on computer technology. "The iPhone 5 is dealing a serious blow to DoCoMo's brand power."
Daiwa Securities Co. analyst Koki Shiraishi said Son was making a smart move with its Sprint acquisition, noting the risks were minor compared with the 2006 takeover of Vodafone Japan, which Son transformed into a profitable company Softbank Mobile.
"The prospects for the latest deal are several notches better, considering the cash cow in its mobile business," he said.
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