Thinking Machines Lab Nears $5B Round at $40B Valuation
Mira Murati's Thinking Machines Lab is reportedly close to a $5 billion round led by Accel at a $40 billion valuation, even as a third of its founders have left.
SUMO· the number puzzle
Dialo· learn languages by speaking
ediviewer· read EDI files like documents
giftdetect· the right gift in minutesThinking Machines Lab, the AI startup founded by former OpenAI chief technology officer Mira Murati, is preparing to raise $5 billion in a new funding round, according to people familiar with the talks. Venture firm Accel is expected to lead the deal, which the company hopes to close as early as this week.
The startup is seeking a valuation of $40 billion before the new money comes in. That is more than three times its worth a year ago. A representative for Thinking Machines Lab declined to comment, and Accel did not respond to a request for comment.
A lower valuation than first sought
The figure is below what the company originally had in mind. Thinking Machines Lab had earlier held talks at a $50 billion valuation, but those discussions did not produce an agreement with investors.
The new round would dwarf the previous one. In July 2025, the company raised $2 billion from investors led by Andreessen Horowitz, at a valuation of more than $10 billion.
A third of the founding team has left
The financial momentum comes with a staffing problem. Around a third of the startup's founders have left, including former CTO Barret Zoph, machine learning researcher Luke Metz and Andrew Tulloch, an engineer focused on AI training infrastructure. Some of the departed staff moved to Meta and OpenAI, which can offer higher salaries and larger compensation packages.
For Murati, the exits hurt in particular. She built the company around specialists who had previously worked at OpenAI, and their ties to the team behind ChatGPT helped the startup win investor attention quickly after she left her post as CTO.
What the company has shipped
The first product from Thinking Machines Lab is Tinker, a tool that lets developers adapt large language models to their own tasks, including programming.
If the round closes, the company will have the capital to compete for talent and compute with much larger rivals. Whether it can keep its remaining researchers, and turn Tinker into a broader product line, will shape how investors view the $40 billion price tag.
Apps worth a look
SUMO: the number puzzleTap the right tiles, add them up, hit the target. Easy to learn, hard to master. Free, for all ages.
Dialo: learn languages by speakingTalk to an AI conversation partner; every sentence comes back corrected and explained in your language. 9 languages, A1 to C2.
ediviewer: read EDI files like documentsOpen EDIFACT and X12 messages, see every segment explained, convert to JSON/XML, export PDF and Excel. Runs locally, no upload.
giftdetect: the right gift in minutesPick who it is for, the occasion and their personality. The search engine reads product descriptions from local shops and ranks what fits. Free, no sign-up.
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