# Thinking Machines Lab raises $5 billion at $40 billion valuation

> The AI startup founded by former OpenAI CTO Mira Murati is closing a funding round that would triple its valuation from last year, even as it loses founding team members to rivals.
- Title: Thinking Machines Lab raises $5 billion at $40 billion…
- Summary: The AI startup founded by former OpenAI CTO Mira Murati is closing a funding round that would triple its valuation from last year, even as it loses founding…
- Keywords: thinking machines lab, mira murati, accel, ai funding, openai, tinker, ai talent, Business Insider
- Source: Business Insider — https://businessinsider.com/thinking-machines-lab-is-closing-5-billion-new-round-2026-11
- Author: Katie Roof
- Published: 2026-11-06T00:40:20.679+00:00
- Read time: 1 min
- Topics: thinking machines lab, mira murati, accel, ai funding, openai, tinker, ai talent, business, technology
## Five billion dollar round closing this week
AI startup Thinking Machines Lab is set to close a fresh round of funding as soon as this week at a forty billion dollar pre-money valuation, led by Accel.
## Valuation triples from last year's round
This round would more than triple Thinking Machines' valuation from its last public round last year, when it was valued at more than ten billion dollars and raised two billion dollars.
## Founded by Mira Murati from OpenAI
Thinking Machines Lab emerged from stealth last year led by Mira Murati, who previously served as OpenAI's chief technology officer. Other key figures helped train early versions of ChatGPT.
## Losing founding members to rivals
About a third of Thinking Machines' founding team has left, including Barret Zoph, Luke Metz, and Andrew Tulloch, driven by huge pay packages from rival AI labs like Meta and OpenAI.
## First product Tinker gains ground
Thinking Machines released a new version of Tinker on Thursday, a system enabling users to fine-tune large language AI models, with the company stating the model has seen gains in AI coding.
## Key takeaway

Thinking Machines Lab is raising five billion dollars at a forty billion dollar valuation, led by Accel, tripling its value from last year despite losing key staff to competitors.