SoftBank-owned Arm debuts on Nasdaq in biggest U.S. IPO this year

Arm Holdings Plc., a British chip designer owned by Japanese investment conglomerate SoftBank Group Corp., debuted on the U.S. Nasdaq stock exchange Thursday, becoming the largest U.S. initial public offering this year with a market capitalization of over $65 billion.

The shares of the chip giant, which commands an overwhelming share of the world’s smartphone processor market, ended the first day of trade at $63.59, surging some 25 percent from its IPO price of $51.

The IPO comes after Arm’s Japanese parent company posted massive losses in the past two years due to investment missteps. SoftBan...