Thinking Machines, an AI lab founded in early 2025 by former OpenAI CTO Mira Murati, is reportedly in discussions to raise a $1 billion funding round at a valuation near $40 billion. The Information first reported this development, with venture capital firm Accel positioned to lead the round, according to sources. If completed, this valuation marks a decrease from the roughly $50 billion target the company pursued late last year.

The startup’s revenue run rate now exceeds $100 million annually, which means the $40 billion valuation implies an extremely high revenue multiple. Thinking Machines, known for its flagship open-weight model called Inkling introduced in July, generates income by charging users based on compute for customizing AI models on proprietary data through its Tinker platform. This novel approach aligns with the company’s ambition to capitalize on advanced AI customization.

Thinking Machines previously raised a $2 billion seed round—the largest of its kind—led by Andreessen Horowitz alongside Nvidia, GV, Lightspeed, and Conviction Partners. At that time, the startup was valued at $12 billion, largely reflecting confidence in the leadership of Murati and key former OpenAI staff who helped establish the company. However, it has seen notable co-founder departures recently, including Lilian Weng and Luke Metz, who have returned to OpenAI.

Accel and Thinking Machines have not publicly commented on the funding talks. As the AI sector’s race continues, all eyes are on how Thinking Machines will leverage its substantial investment and talent pool to deliver on expectations at this lofty valuation. The outcome of this financing round will be a significant milestone in the evolving landscape of AI innovation and startup funding.