SoftBank Group Corp is building up stakes in Nvidia and Taiwan Semiconductor Manufacturing Co (TSMC), showing founder Masayoshi Son’s focus on the tools and hardware underpinning artificial intelligence. The Japanese technology investor raised its stake in Nvidia to about US$3 billion by the end of March, up from US$1 billion in the prior quarter, according to regulatory filings. It bought around US$330 million worth of TSMC shares and US$170 million in Oracle Corp, the filings show. That was...