Reuters was first to report that SoftBank Group (9984.T) CEO Masayoshi Son was in San Francisco on Wednesday when he joined a call with his bankers in New York to make a final decision about his company’s most valuable asset: chip designer Arm Holdings (ARM.O). Arm’s blockbuster initial public offering (IPO) was oversubscribed by 12 times, and could have been priced at $52 per share, above the indicated range of $47 to $51.