(Bloomberg) -- The shares of SoftBank Group Corp.’s Japanese telecom business fell at the start of trading on the Tokyo Stock Exchange after Masayoshi Son raised more than $20 billion in an initial public offering.

SoftBank Corp. declined 6.4 percent to 1,404 yen as of 9:01 a.m. in Tokyo on Wednesday, compared with 1,500 yen, the price at which the stock was sold to investors in the offering.

SoftBank stuck to its price for the offering instead of a range, even amid a Japan-wide network outage and a continuing global equities selloff. Son is selling a stake in his crown-jewel domestic telecoms business to fund further investments in global technology companies, a portfolio that already includes Uber Technologies Inc. and WeWork Cos.

Including an overallotment of about 160 million shares, SoftBank is selling a total of roughly 1.76 billion shares. The 2.65 trillion yen ($23.6 billion) listing includes the cash-generating businesses spanning wireless, broadband and fixed-line services.

Nomura Holdings Inc., Deutsche Bank AG, JPMorgan Chase & Co., Sumitomo Mitsui Financial Group Inc., Mizuho Financial Group Inc. and Goldman Sachs Group Inc. are the joint global coordinators.

Son is transforming his Tokyo-based company from a telecom operator into a global tech investor, but the listing comes at a time when Japan’s wireless industry has come under pressure from the government to reduce phone bills. The entry of e-commerce giant Rakuten Inc. is also raising the risks of a price war next year.

To contact the reporter on this story: Pavel Alpeyev in Tokyo at palpeyev@bloomberg.net

To contact the editors responsible for this story: Robert Fenner at rfenner@bloomberg.net, Reed Stevenson

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