SoftBank's dip shows worry about OpenAI

OpenAI pressured by debut of Gemini 3.0

- MAYUMI NEGISHI KENTARO TSUTSUMI

Growing unease over frothy artificial intelligence valuations is weighing on shares of SoftBank Group Corp, which traders increasingly view as a proxy for privately held OpenAI.

The Japanese tech investor sits at the forefront of a global AI selloff amid worries about new pressure on OpenAI following Alphabet Inc's Gemini 3.0 debut. SoftBank shares have plunged around 40% since late October, erasing over ¥16 trillion ($102 billion) in market value, as its founder Masayoshi Son prepares to double down on OpenAI and the infrastructure that supports it.

SoftBank has ridden the global Al investment boom faster than any other Japanese company. Its exposure to OpenAI — and a $14.6 billion gain on that stake — helped it post a surprise ¥2.5 trillion net income in the fiscal second quarter, putting it on track for one of its highest annual profits.