Tokyo's frontier AI research lab — nature-inspired foundation models for Japan and the world
HQ: Tokyo, Japan | Founded: 2023 | Employees: ~50 (2026) | Stage: Late Stage VC (Series B) | Website: https://sakana.ai
Sakana AI is a frontier AI research and development company founded in Tokyo in July 2023 by David Ha (CEO, former Google Brain research scientist and head of research at Stability AI), Llion Jones (CTO, co-author of the landmark Transformer paper 'Attention Is All You Need' and former Google Brain engineer), and Ren Ito (COO/Chairman). The company's thesis, articulated at founding, is to build AI inspired by nature — using evolutionary algorithms, self-organization, and swarm intelligence rather than only scaling up monolithic models.
That approach has produced a distinctive research portfolio: evolutionary model merging that creates new models by combining existing ones (including some of the first 'Tokyo 7B' and Japanese-language foundation models), the viral 'The AI Scientist' — a fully autonomous agent that generates and evaluates its own research papers, with papers accepted at top workshops — and 'AI CUDA Engineer' for automatic kernel optimization. On the product side, Sakana builds Japanese AI services, research assistants, and model orchestration APIs, positioning itself as Japan's foundation-model champion with Japanese-language quality as a moat.
Sakana became Japan's fastest unicorn when its Series A (led by NEA, Khosla Ventures, and Lux Capital, with NVIDIA investing) valued it above $1.1 billion in September 2024. In November 2025 it raised a ¥20 billion ($135M) Series B at a $2.65 billion post-money valuation — led by a mix of Japanese and global investors including MUFG, Khosla Ventures, and Macquarie — later expanded to roughly $200 million, making it Japan's most valuable private startup. The company now works with NTT on Japanese-language foundation models, MUFG on financial AI, and Japan's Ministry of Defense on AI for national security, while keeping a lean team of roughly 50 researchers.
Sakana AI — 'sakana' means fish in Japanese — is Japan's most valuable private AI company, built on a contrarian bet: instead of chasing larger general-purpose models with ever more compute, it applies nature-inspired algorithms (evolutionary model merging, swarm intelligence, automated scientific discovery) to build efficient, specialized models. Its founding team is arguably the strongest in Asia (a Transformer co-author and a former Google Brain lead), and its strategic positioning — Japanese-language foundation models, partnerships with NTT, MUFG, and Japan's defense establishment, and the viral 'AI Scientist' research agent — gives it a national-champion tailwind no U.S. lab enjoys. The bear case is the same one that dogs all research labs: monetization is unproven, compute scale lags the frontier, and its research agenda, however elegant, may not translate into durable commercial advantage.
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