FILE PHOTO: SoftBank Corp. placard is prepared during a ceremony to mark the company's debut on the Tokyo Stock Exchange in Tokyo, Japan December 19, 2018. REUTERS/Issei Kato/File Photo

TOKYO (Reuters) - Japan’s SoftBank Corp said on Wednesday it would buy 456.5 billion yen ($4.15 billion) worth of new shares to be issued by Yahoo Japan Corp, boosting its stake to 44.64 percent from 12.08 percent.