MUFG now Sakana AI’s largest Japanese investor

Its projects include an AI capable of rewriting its own code for self-improvement.

Mitsubishi UFJ Financial Group (MUFG) and its subsidiary MUFG Bank is making a second investment in Sakana AI K.K., and AI research and development (R&D) company.

The investment, amount undisclosed, is expected to make MUFG the largest Japanese investor in Sakana AI.

Sakana AI’s projects include the “AB MCTS,” which leverages the strengths and weaknesses of multiple AI models to solve complex problems, and the “Darwin Gödel Machine,” an AI capable of rewriting its own code for self-improvement.

Sakana AI recently established an “Applied Team” to expand its efforts in AI social implementation, which involves linking its research achievements and technologies to real-world business challenges, MUFG said in a press release.

MUFG first invested in Sakana AI in its series A funding round in September 2024. MUFG Bank, meanwhile, entered into a partnership agreement with Sakana AI in May 2025. The bank had been working together to implement AI solutions aimed at addressing the bank’s business challenges, it said.