Shares of SoftBank Group jumped 16.5% after Japanese markets reopened following the Golden Week holidays, as investors rushed into AI-related technology stocks. The rally reflected growing optimism around artificial intelligence infrastructure, semiconductor demand, and SoftBank’s increasing exposure to leading AI companies.
A major driver behind the surge was investor enthusiasm surrounding SoftBank’s aggressive investment in OpenAI. The company’s cumulative commitment to OpenAI has reportedly risen to around $64.6 billion, giving SoftBank a significant stake in one of the world’s leading AI firms. Investors are increasingly viewing SoftBank as a public-market proxy for the AI boom, particularly because OpenAI remains privately held.
The rally was also fuelled by strength in semiconductor stocks globally. SoftBank owns a major stake in Arm Holdings, whose chip designs are widely used in AI data centres and energy-efficient computing systems. Rising expectations around AI infrastructure spending and strong momentum in global chipmakers such as AMD and Nvidia helped lift sentiment across Asian technology markets.
Japan’s broader stock market benefited from the AI-driven optimism as well. Investors poured into semiconductor and AI-related companies, mirroring similar rallies seen in South Korea and the United States. The enthusiasm follows growing forecasts that AI-related computing demand will continue to expand rapidly over the coming years, driving growth for companies involved in chips, cloud infrastructure, and AI platforms.
Despite the strong rally, analysts note that SoftBank’s strategy also carries significant financial risk due to its large leveraged bets on AI companies and infrastructure. However, for now, investor sentiment remains strongly positive as markets continue rewarding firms positioned at the centre of the global AI expansion. The latest surge underscores how artificial intelligence has become one of the dominant forces shaping global equity markets and technology investments.
