Initially, he was the only full-time employee at SoftBank, which, despite sounding like a tech start-up, operated “like an investment fund, with a portfolio of holdings
that Son would adjust based on changing growth rates,” Mr. Miki said.
The 59-year-old technology investor — a grandson of South Korean immigrants who has amassed one of Japan’s largest personal fortunes by pursuing grand,
Silicon Valley-inspired visions — is best known outside his homeland for buying the American mobile phone carrier Sprint for $21.6 billion in 2013.
“The goal was to become a 100 trillion-yen company,” Mr. Miki said, an amount equal to about $1 trillion.
SoftBank is buying ARM for a rich $32 billion, and it plans to plow another $25 billion in the Saudi joint venture over the next five years.
His goal is nothing less than to change how the material world works —
and to turn his company, the SoftBank Group, into the future’s most important technology business.
The investment displayed Mr. Son’s willingness to act on a general conviction: in this case,
that web portals would be crucial to the early commercial development of the internet.
And he is collaborating with Saudi Arabia’s ruling family to create what could become the world’s largest technology investment fund.
One item in the portfolio was Yahoo, an early investment that earned Mr.