May 15, 2026 /SemiMedia/ — Denso has withdrawn its acquisition proposal for Rohm, adding new uncertainty to Japan’s power semiconductor consolidation plans. Talks involving Rohm, Toshiba and Mitsubishi Electric are continuing, but no clear structure has been finalized.

The main issue remains management control and operational integration. Rohm President Katsumi Azuma said combining manufacturing, R&D and sales operations could reduce decision-making efficiency if multiple companies share control.

While negotiations continue, Toshiba and Mitsubishi Electric have already moved ahead with separate 300mm wafer production investments. Because production strategies are now being developed independently, future cooperation may provide limited benefits in process standardization and manufacturing scale.

European competitors including Infineon Technologies and STMicroelectronics have expanded aggressively in automotive power semiconductors and SiC devices, while also accelerating 300mm wafer production plans.

Toyota group companies had hoped to strengthen automotive semiconductor supply chains through a Denso-Rohm deal, but Rohm’s position on maintaining management independence prevented the plan from moving forward.

Japan’s power semiconductor suppliers are now facing pressure from both European manufacturers in high-end automotive applications and Chinese competitors expanding production capacity in the mainstream market. Continued delays in consolidation could weaken Japan’s position in the global power semiconductor industry.