SK Hynix Weighs Japan NAND Cooperation as Kioxia Stake Remains Unsettled

SK Hynix is considering closer cooperation with Japanese customers and suppliers to develop the NAND flash market, but the idea is still exploratory. CEO Kwak Noh-jung said the company was “very carefully looking” at how to co-develop the market—not announcing a specific partnership. Meanwhile, SK Hynix’s Indiana project is moving forward as a separate investment in high-bandwidth memory (HBM). 117

Japan NAND cooperation is under consideration, not confirmed

Kwak’s comments point to a possible deeper relationship with Japanese customers and suppliers around NAND flash. They do not establish that SK Hynix and any Japanese company have agreed to joint production, a joint venture or a new facility. The available remarks describe the company as examining how cooperation might develop. 110

That distinction matters in Kioxia’s case: the two companies are connected through SK Hynix’s indirect investment, but they also compete in NAND flash. Closer cooperation would therefore be a potential commercial development, not proof that the companies have combined operations. 12

What SK Hynix’s indirect Kioxia stake means

SK Hynix’s Kioxia interest is held indirectly through a Bain Capital-affiliated investment vehicle, rather than as a direct holding in the company’s own name. Reporting has described that vehicle as Kioxia’s largest shareholder, while noting that SK Hynix’s ability to directly influence Kioxia’s management is limited.

Kwak said SK Hynix had no fixed plans for the stake. His comments leave open the possibility of closer NAND-market cooperation, but they do not announce a change to the investment or a plan to use it to direct Kioxia’s decisions. 16

Indiana is a separate HBM investment

SK Hynix is investing more than $4 billion in an advanced packaging plant in West Lafayette, Indiana. The project is intended to become the company’s first U.S. HBM production base. SK Hynix says mass production of next-generation HBM is planned for the second half of 2029; Reuters reported a target of third-quarter 2029 volume production for HBM4E. 1517

Kwak described Indiana as a future key HBM production base in the United States by 2030. The project is a concrete manufacturing commitment, unlike the still-unsettled discussions about deeper cooperation in Japan.

Further U.S. investment and Solidigm listing remain undecided

Kwak said SK Hynix was open to additional investment in the United States but had not made a decision. His comments signal openness to opportunities, not a confirmed next project. 5

A possible U.S. initial public offering for Solidigm, SK Hynix’s NAND subsidiary, also remains unresolved. Kwak said the listing was still under discussion and had not been withdrawn. 89

What is confirmed—and what is not

The clearest distinction is between projects underway and possibilities still being assessed: SK Hynix has broken ground on its Indiana HBM plant, while its comments about Japan describe cautious exploration. The company has announced no specific Japanese NAND partnership, no fixed plan for its indirect Kioxia stake, and no decision on further U.S. investment or a Solidigm listing. 11516