I was wondering why Masayoshi Son has a monosyllabic surname. I’ve never seen a Japanese surname like it.
Turns out it is a Korean name. Son is a 3rd generation "Zainichi Korean", which are ethnic Koreans with permanent residency or citizenship in Japan.
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Son's family had adopted the Japanese surname Yasumoto (安本), and Son had used that surname as a child.[9] He decided to use his Korean surname instead on returning to Japan from the U.S.,[15] and became a role model for ethnic Korean children in Japan.[15]