Accel in Talks to Lead Thinking Machines’ $1B Round at $40B Valuation
Accel may lead a $1 billion Thinking Machines round at a $40 billion valuation as revenue tops $100 million, despite several co-founders leaving for OpenAI.
Summary
Thinking Machines, founded in early 2025 by former OpenAI CTO Mira Murati, was discussing a $1 billion raise on September 3, 2026, at a valuation of at least $40 billion. Existing investor Accel is in talks to lead the round, which may not close and would fall below the $50 billion valuation sought in late 2025. The AI lab’s annual revenue run rate exceeds $100 million, making the proposed valuation an extraordinarily high revenue multiple. Accel and Thinking Machines did not immediately comment.
In July 2026, Thinking Machines introduced Inkling, an open-weight model that generates revenue through usage-based compute fees when customers adapt models to proprietary data on its Tinker platform. Its previous $2 billion financing, among history’s largest seed rounds, valued the company at $12 billion. Andreessen Horowitz led that investment, joined by Nvidia, GV, Lightspeed and Conviction Partners, largely backing Murati and her team of former OpenAI researchers. Several prominent co-founders have since departed, including Lilian Weng and Luke Metz, who returned to OpenAI.
Positives
- $1 billion in potential funding could give Thinking Machines substantial capital to expand its AI models and Tinker platform.
- More than $100 million in annual revenue run rate shows the startup has established meaningful commercial demand.
- Inkling earns usage-based compute fees from customers adapting models to proprietary data through Tinker.
- $2 billion in prior financing attracted Andreessen Horowitz, Nvidia, GV, Lightspeed and Conviction Partners.
- At least a $40 billion proposed valuation would more than triple the company’s previous $12 billion mark.
Risks & concerns
- At least a $40 billion valuation against revenue above $100 million represents an extraordinarily high revenue multiple.
- $40 billion would remain below the $50 billion valuation Thinking Machines sought in late 2025.
- Lilian Weng and Luke Metz are among several prominent co-founders who have left for OpenAI.
- Accel and Thinking Machines have not commented, and the proposed $1 billion round may not be completed.