Japan and Korea AI Infrastructure: SoftBank, Sakura, SK — 2026-09-12

Top developments

SK Group Chairman Visits Ulsan AI Data Center Site

On September 10, SK Group Chairman Chey Tae-won made his first visit to the construction site of the "SK AI Data Center Ulsan" since ground broke in August 2025. The 7 trillion won ($5.3 billion) facility is scheduled to begin operations in the second half of next year and is being positioned as the core hub for SK’s AI transformation (AX) strategy. This high-level inspection underscores the urgency for Korean conglomerates to secure domestic compute capacity amidst global GPU shortages.

SoftBank Repays $40 Billion Bridge Loan for OpenAI

SoftBank Group announced on September 9 that it will repay the balance on a $40 billion bridge loan used to finance its investment in OpenAI. The move indicates SoftBank is proceeding with plans to refinance the deal with longer-term debt, stabilizing its capital structure while it continues to fund global AI infrastructure projects like Project Stargate. This financial maneuvering frees up balance sheet flexibility for further investments in Japanese and international data centers.

Naver Deploys 4,000 GPUs for National Security AI

Naver Cloud announced it is deploying 4,000 GPUs specifically for national security applications, aiming to create a sovereign AI shield for South Korea. The company stated that reliance on foreign models in cyber security domains is unacceptable, positioning its proprietary technology as essential for state-level infrastructure. This initiative highlights the shift toward "sovereign AI" where nations prioritize domestic control over critical computational resources.

Samsung SDS CEO Signals Strategic AI Investments

Samsung SDS CEO Lee Jun-hee stated on September 8 that the company will actively pursue strategic investments in AI, robotics, and logistics sectors. This announcement aligns with Samsung SDS's broader narrative of moving from theoretical AI frameworks to practical execution in enterprise environments. LS Securities maintained a "Buy" recommendation with a target price of 307,000 won, citing this shift toward tangible AI infrastructure execution.

Local view

Korean media outlets like The Korea Economic Daily and Yonhap News are closely tracking the "Sovereign AI" trend, emphasizing that companies like Naver are not just building commercial clouds but fulfilling national security mandates by isolating sensitive data from global models. In Japan, Impress Watch notes that while large-scale AI data center plans finally began materializing in early 2026, the country faces significant challenges in competing with global hubs due to power constraints and slower regulatory approval compared to the US and Middle East.

Context & numbers

South Korea’s Ministry of Science and ICT (MSIT) has confirmed that the next-generation national supercomputer, featuring 8,496 GPUs and 614 petaflops of performance, will launch by December 2026. Japan continues to attract significant capital, with Microsoft’s $10 billion investment in local AI infrastructure through 2029 serving as a key benchmark for foreign direct investment in the sector.

On the radar

• December 2026: Launch of South Korea’s 614-petaflop national supercomputer.
• Q4 2026: Expected operational readiness for major private AI data centers in Ulsan and Osaka, pending final power grid connections.