Hitachi shares surge nearly 10% after OpenAI partnership announcement, marking biggest rally since April

Japanese industrial giant Hitachi Ltd witnessed its sharpest intraday stock surge since April 2025, climbing as much as 9.9% to ¥4,285 in Tokyo trading on October 3, following the announcement of a strategic partnership with OpenAI. The rally came after both companies signed a memorandum of understanding (MoU) to collaborate on building sustainable energy infrastructure and artificial intelligence (AI) capabilities, including support for OpenAI’s global data center expansion.

The deal was finalized during a high-profile meeting in Tokyo between Hitachi CEO Tokshiaki Tokunaga and OpenAI CEO Sam Altman, who is currently on a multi-nation tour across Asia to secure partnerships for OpenAI’s Stargate infrastructure initiative. The agreement positions Hitachi as a key supplier of power transmission, distribution equipment, and cooling systems for OpenAI’s next-generation AI data centers.

Hitachi–OpenAI Partnership Highlights

The announcement triggered a wave of optimism across Japan’s tech and industrial sectors, with Hitachi emerging as the top performer on the Nikkei 225 index. The benchmark index itself rose 1.85% to close at 45,769.50, while the Topix gained 1.35% to end at 3,129.17. Other AI-linked stocks also rallied, including Renesas Electronics (+8%), Advantest Corp (+3.4%), and Tokyo Electron (+2.3%).

Hitachi Stock Performance – October 3, 2025

The partnership is expected to benefit Hitachi Energy, a subsidiary that manufactures electricity transmission equipment and provides digital solutions for renewable energy and smart grids. The company’s Lumada platform will also be integrated with OpenAI’s models to enhance predictive analytics and operational efficiency across industrial clients.

OpenAI’s Stargate initiative, aimed at building hyperscale data centers across Asia and North America, has already secured preliminary agreements with Samsung Electronics and SK Hynix earlier this week. Hitachi’s inclusion adds a critical energy dimension to the project, ensuring that AI growth is powered by reliable and sustainable infrastructure.

OpenAI’s Stargate Initiative – Key Partners

Hitachi’s CEO Tokshiaki Tokunaga emphasized the strategic importance of the deal. “AI is the future of industrial transformation, and energy is its backbone. Our collaboration with OpenAI will ensure that the next wave of AI innovation is built on sustainable and scalable infrastructure,” he said in a statement.

Sam Altman echoed the sentiment, stating, “We’re thrilled to partner with Hitachi. Their expertise in energy and infrastructure is vital to our mission of making AI accessible and impactful globally.”

The news also sparked investor interest in other Japanese conglomerates with exposure to AI and energy. SoftBank Group, a major OpenAI investor, rose 3.6%, while chipmakers like Renesas and Tokyo Electron saw strong buying interest.

Japan’s AI-Linked Stocks – October 3 Rally

Analysts believe the partnership could unlock new revenue streams for Hitachi, especially in the AI-powered industrial automation and smart grid segments. “This is a transformative deal for Hitachi. It aligns with global trends in AI, energy efficiency, and digital infrastructure,” said Hiroshi Tanaka, senior analyst at Nomura Securities.

The broader Asia-Pacific markets traded mixed, with Chinese and South Korean exchanges closed for holidays. India’s Nifty 50 and BSE Sensex remained flat, while Australia’s ASX/S&P 200 rose 0.46%.

Social media platforms and investor forums lit up with reactions to the announcement, with hashtags like #HitachiOpenAI, #AIInfrastructure, and #StargateProject trending across Twitter/X, LinkedIn, and YouTube.

Public Sentiment – Social Media Buzz on Hitachi–OpenAI Deal

In conclusion, Hitachi’s partnership with OpenAI has not only triggered a stock market rally but also positioned the Japanese conglomerate as a key player in the future of AI infrastructure. As the Stargate initiative gains momentum, Hitachi’s energy expertise and global footprint could play a pivotal role in shaping the next generation of intelligent systems.

Disclaimer: This article is based on publicly available financial reports, verified news coverage, and official company statements. It does not constitute investment advice or prediction of any stock performance. All quotes are attributed to public figures and institutions as per coverage. Readers are advised to follow official exchange filings and financial disclosures for verified information.