The new entity, SB OpenAI Japan, will be co-owned by OpenAI and a company established by SoftBank and its domestic telecom unit.
Following the announcement, OpenAI CEO Sam Altman and SoftBank founder Masayoshi Son met with Japanese Prime Minister Shigeru Ishiba on Monday, highlighting the venture’s strategic significance.
As part of the partnership, SoftBank will pay US$3 billion annually to integrate OpenAI’s technology across its various businesses. The company also plans to invest between US$15 billion and US$25 billion in OpenAI, in addition to its US$15 billion commitment to Stargate, a separate AI infrastructure initiative backed by OpenAI and Oracle to expand AI capacity in the US.
The massive investment comes as AI competition heats up globally. China’s DeepSeek, a rising AI player, has drawn attention for developing a model that appears to rival the capabilities of leading US firms, prompting questions about the scale of investment being funneled into AI.
For Son, this marks a return to aggressive dealmaking after a period of caution due to the declining value of SoftBank’s tech portfolio and previous high-profile investment missteps. His renewed backing of OpenAI signals a strong bet on AI’s future role in business and technology.