Private companies№ 23AI research and tools, San Francisco

Thinking Machines Lab

Mira Murati's AI lab sells fine-tuning tools and open models, valued at $12B, now in talks at $40B+.

Private companyUpdated 16 min readPedrum Shokouhi

Thin moat

This company is private. It has no public share price and you cannot buy it on an exchange. Valuations come from funding rounds and press reports and can be out of date. No IPO plan reported. Research, not investment advice.

Key facts

  • FoundedLaunched February 2025 in San Francisco, as a public benefit corporation6
  • CEOMira Murati (cofounder)21
  • StaffAbout 120 (press-reported, March 2026)13
  • RevenueNot published. Press-reported: more than $100M (TechCrunch) to hundreds of millions (The Information), annualised16
  • Last closed roundAbout $2B seed at $12B post-money, July 20259
  • Pending talks$5B to $6B at $40B+ pre-money (press-reported, not closed)16
  • Compute dealAt least 1 gigawatt of Nvidia Vera Rubin systems, from early 202710
  • ProductsTinker (fine-tuning API); Inkling and Inkling-Small (open-weights models)2

The answer

  1. Thinking Machines Lab is a private AI company, founded in 2025 by former OpenAI CTO Mira Murati, selling a fine-tuning service called Tinker and releasing open-weights Inkling models26.
  2. Its last closed valuation was $12B in July 20259, and press reports say it is negotiating $5B to $6B at $40B or more before the new money, against press-reported revenue of $100M to a few hundred million16.
  3. My model gives a base value of about $12B, with a wide range of $1B to $75B, so the talks price looks well above what public data supports, though not impossible if a frontier model succeeds.

Six questions, one line each

Why does the business win?
It has not clearly won yet: Tinker has real customers3 and Inkling got attention2, but revenue is small against its plans16.
What is the moat?
Thin. People and Nvidia compute, but customers can switch and open models can be copied3.
What is the advantage?
A strong research team, a founder network and a gigawatt compute deal starting 202710.
Who runs it?
Mira Murati, CEO, with John Schulman and Soumith Chintala; four cofounders have left2116.
What is the margin of safety?
None at talks pricing: my base is about $12B, less 25% is about $9B, against $40B+16.
What is the price?
$12B post-money in July 20259; $40B+ pre-money under negotiation, not closed16.

What it does

Thinking Machines Lab is a private artificial intelligence company in San Francisco. It was launched in February 2025 by Mira Murati, who had been chief technology officer of OpenAI6. It is not listed on any stock exchange. Its shares cannot be bought on the open market, and no public filing shows its accounts. Everything below about its money comes from press reports and a few company posts, so read the numbers as estimates.

The company says it wants to make AI systems more widely understood, customisable and generally capable, and that it publishes research, papers and code1. In practice it has shipped two kinds of thing so far.

The first is Tinker, launched on 1 October 2025 and made generally available on 12 December 20252. Tinker is a developer service for fine-tuning. Fine-tuning means taking an existing AI model and training it further on your own data or tasks so it does one job better. With Tinker the customer writes the training loop, the reward functions (the scoring rules used in reinforcement learning) and decides when to save checkpoints, while Thinking Machines runs the graphics-chip infrastructure3. The page lists customers such as Bridgewater, Glean, Exa, Mercor and Krea, plus university researchers3.

The second is its own models. On 15 July 2026 it released Inkling, an open-weights model, and on 30 July 2026 a smaller one, Inkling-Small2. Open-weights means the trained model files can be downloaded and run by anyone, though the training data and code may not be shared. The company’s release post describes Inkling as a mixture-of-experts model with 975 billion total parameters (a rough measure of model size), of which 41 billion are active at a time. It says the design largely follows DeepSeek-V3 and that post-training began with a fine-tuning step on synthetic data generated by open-weights models including Moonshot’s Kimi K2.522. Inkling is also offered through a serverless inference service, still in beta3.

What the company has not shown, as of early November 2026, is a closed frontier model sold to the public the way ChatGPT or Claude is. Its public pitch is human and AI collaboration and models people can shape themselves110. I cannot judge from outside how good its unreleased research is.

A plain way to see the company: it has two businesses of very different size. One is a software service with usage-based pricing, which can be run with few staff and has a clear customer list3. The other is a bet on training large models, which costs far more and has no sales yet. The valuation talks are almost entirely about the second. A reader trying to judge the company should keep the two apart, because the first could be a decent business on its own and still not justify a price set for the second.

The papers and blog posts matter more here than at a normal software firm. The news page shows research posts on reinforcement learning for text-to-SQL, expert judgment in financial tasks and forecasting world events with a partner, Mantic, as well as safety and interactivity research grants2. This is how the company recruits and builds a name, and it is also a hint at where it sees paying work: finance, search, data and code3.

How it makes money

The company has not published revenue. The best public clue is usage pricing on the Tinker page: customers pay per million tokens (a token is a small chunk of text) for training, sampling and prefill, plus $0.10 per gigabyte per month for stored checkpoints, with rates varying by model3. Serverless inference for Inkling is billed per million tokens of input and output3. PYMNTS, citing The Information, describes the model as selling tools that let businesses customise AI with their own data while giving open-weight models away17.

Revenue estimates conflict. The Information, via reporter Stephanie Palazzolo, put annualised revenue in the hundreds of millions of dollars. TechCrunch, using another source, put it above $100 million16. Annualised means a recent month or quarter multiplied up to a year, so it overstates a full year if growth is lumpy. RuntimeWire points out these figures are self-reported by the company to reporters and unaudited14. I use $0.3 billion as a midpoint for the base case. That is my estimate, not a reported number.

On the other side of the ledger, costs are very large. Training and serving big models needs rented or owned graphics chips. The Nvidia agreement covers at least one gigawatt of systems, and the Financial Times, as relayed by The Next Web, said the chip arrangement alone is worth tens of billions of dollars11. Jensen Huang has said a gigawatt of data-centre capacity can cost up to $50 billion11. No source says how much of that Thinking Machines itself must pay, and how it is financed is not public. That gap is the single biggest unknown in valuing this company.

Two ideas help in reading the revenue range. Fine-tuning demand tends to be lumpy: a handful of large customers running big training jobs can lift a quarter’s usage and then pause. And if revenue is mostly compute resold with a margin, gross profit is much lower than for ordinary software. The company has not said which it is. I assume a modest gross margin in the base case, and that is part of why I use a terminal multiple of 10 times sales, not the higher multiples of the software names above.

Revenue and funding figures, with source type

MetricValueSource
Annualised revenue, low press estimateMore than $100M (press-reported)16
Annualised revenue, high press estimateHundreds of millions (press-reported)16
Tinker storage price$0.10 per GB per month (reported by company)3
Seed round, July 2025About $2B at $12B post-money (reported)9
Capital raised since founding, per TechCrunch, March 2026More than $2B (reported)10
Pending round$5B to $6B at $40B+ pre-money, talks only (press-reported)16

The market and the competition

Thinking Machines competes in two markets at once. In the developer tools market, Tinker competes with fine-tuning services from the large model makers and cloud providers, and with open-source training software that customers run themselves. The Tinker page supports models from Moonshot, Z.ai, Qwen, OpenAI (gpt-oss), DeepSeek and Nvidia as well as Thinking Machines’ own3. That helps customers, and it also shows Tinker is a layer on other people’s models, not a lock on one.

In the model market, the company says it wants to build frontier models, meaning the most capable systems1. The Daily Upside reads the Nvidia deal as a sign it intends to compete with Anthropic, Google, OpenAI, Meta and Alibaba, though the company has not said so in those terms12. TechCrunch’s seed coverage also named OpenAI, Anthropic and Google DeepMind as rivals9. These competitors have far more revenue and compute. I do not have a verified, current figure for their revenue from a source I opened, so I make no numeric comparison here.

Open-weights models are a double-edged choice. They win attention and trust with researchers, and Tinker customers can build on them. But giving the model away makes it hard to charge for the model itself, so money has to come from services around it: training, hosting and support17.

How it could be disrupted from below: cheap open models are improving quickly, and tools that make fine-tuning easier are getting more common. If a customer can fine-tune a good open model on its own servers in an afternoon, a hosted service has to offer reliability, scale and support to earn its fee. Tinker’s pitch includes automatic retry if a graphics chip fails, security options such as customer-managed encryption keys, and audit logs3. These are real features for large buyers. They are also things cloud providers already sell.

How it could be disrupted from above: a large lab could bundle fine-tuning with its own frontier model at low or no extra price. That would turn Tinker from a product into a feature. I have no source saying this has happened, so I treat it as a risk, not a fact.

The moat and how it could be disrupted

I rate the moat as thin. The company has real strengths: a founder with a strong network, a research team with a record at OpenAI, PyTorch and others1, and now a large compute commitment with Nvidia10. But none of these yet produces the sort of protection that keeps a customer from leaving.

Switching costs for Tinker look low to moderate. A customer’s training recipes and reward functions are theirs, and the service runs on open-weight models, so moving to another trainer is mostly an engineering job3. There is no network effect I can see. Data advantage is limited: the company states it does not train on customer content3, which is good for trust and means it does not accumulate customer data.

People are the main asset and also the main risk. Of the six cofounders named in early coverage, four have left by early November 2026: Andrew Tulloch went to Meta, Barret Zoph and Luke Metz returned to OpenAI in January 2026, and Lilian Weng left in July 202616. Murati and John Schulman remain, and Soumith Chintala, co-creator of PyTorch, now leads technical work16. Axios, cited by The Neuron, said hires outnumbered departures and headcount grew from about 30 to about 12013. Both can be true.

Compute is a form of scale, but it is rentable by anyone with money, and the Vera Rubin systems are not due until early 202716. A deal signed before the hardware exists is a promise, not an advantage already in place11. If better open models appear from larger labs, or if a rival offers cheaper fine-tuning, the case for paying Thinking Machines weakens.

What an owner could actually take out is an open question. Nobody who holds shares in a private company of this kind can sell them freely. There is no dividend and none is plausible while the company is spending on compute. Returns would come only from a later sale of shares, an acquisition or a listing. A strong founder vote16 means an outside holder cannot force any of those. Secondary sales, where early holders sell to new buyers, may be allowed only with company approval, and I have no source on that. Pooled funds such as the one in the Form D carry their own fees and terms4.

Thin moat

A strong team and Nvidia compute, but low switching costs, open weights and repeated cofounder exits leave little durable protection.

Where the advantage comes from

  • Founder and researcher network from OpenAI and PyTorch1
  • Nvidia partnership and planned gigawatt of compute from 202710
  • Trust position: states it does not train on customer content3
  • Brand among AI researchers; open-weights release attracted attention2

How it could be disrupted

  • More cofounders and senior researchers leave for larger labs
  • Larger labs offer cheaper or better fine-tuning on the same open models
  • Open models from other labs match Inkling, leaving little to charge for
  • Cannot fund the compute commitment, forcing a down round or a sale
  • Customers move training in-house on open-source tools

Scale: very hard to disrupt, strong moat, can be disrupted, thin moat. Rated for the company as it is today.

The numbers we can see

There are almost no hard numbers. The company files nothing publicly beyond one small SEC notice. That notice, a Form D filed on 27 June 2025, belongs to a special-purpose fund set up by Sydecar that sold $595,030 to 14 investors on a first sale date of 11 June 20254. It tells us that small investors pooled money into the company through a fund. It does not show the company’s own accounts, and I did not find any Form D from the operating company itself in the EDGAR search I ran5.

Valuation history, all reported: Bloomberg said in June 2025 that the company was raising close to $2 billion at $10 billion before the money went in8. TechCrunch reported the round closed in July at $12 billion, led by Andreessen Horowitz, with Nvidia, Accel, ServiceNow, Cisco, AMD and Jane Street9. Bloomberg reported in November 2025 early talks at about $50 billion, with some figures up to $60 billion717. Those talks did not close14. In September 2026, The Information reported talks for $5 billion to $6 billion at a pre-money value of at least $40 billion, with Accel in talks to lead and Nvidia giving roughly half16. An earlier version of the story had said just over $1 billion14. Sources disagree on size, and none shows a signed deal as of 3 November 2026.

Simple arithmetic on the pending round: $40 billion divided by revenue of $100 million to a few hundred million is roughly 80 to 400 times annualised sales, as The Next Web notes16. For comparison, on 2 to 3 November 2026 Palantir traded at 57 times trailing sales18, Snowflake at 18.6 times19 and Nvidia at 16.0 times20. Those are enterprise value to trailing twelve-month revenue, from StockAnalysis.

Compared with others in the same line, two points stand out. The company has lost senior people faster than most young labs, and some of those moves were to rivals who are also its competition for hires1316. And its own post-launch momentum has been product-led: Tinker in October 2025, general availability in December, a gigawatt deal in March, Inkling in July, and one-year Tinker notes in October 20262. That is a steady record of shipping, which is a point in its favour that I weigh against the departures.

The numbers I would most like to see are cash on hand, the split of revenue between customers, gross margin on Tinker, and the cost schedule of the Nvidia commitment. None is public. Until at least some arrive, any valuation of this company is mostly a view on what a frontier AI lab is worth, not on what this firm earns.

Public comparables used in my model (enterprise value to trailing revenue, as of 2 November 2026 close)

CompanyEV / salesSource
Palantir57.4x18
Snowflake18.6x19
Nvidia16.0x20
Thinking Machines at $40B pre-money, on $100M to $400MAbout 100x to 400x (my arithmetic, press revenue)16

Reported valuation points

US$ billions 8916

10Jun 2025 pre-money12Jul 2025 post-money40Sep 2026 talks pre-money (floor)

Who runs it and who owns it

Mira Murati is chief executive. She was OpenAI’s chief technology officer before leaving in September 202411. John Schulman, an OpenAI co-founder, is chief scientist6. Press reports say Murati turned down an acquisition approach from Meta in 2025911.

On control, The Next Web reports that Murati holds voting control over the board on major corporate decisions, whatever the other directors do16. If that is right, outside investors, including at $40 billion, would hold little say. I could not verify it from a company filing.

Known investors from the seed round are Andreessen Horowitz (lead), Nvidia, Accel, ServiceNow, Cisco, AMD and Jane Street9. Conviction Partners was also named8. Albania’s public broadcaster RTSH reported in May 2025 that the Albanian government had decided to invest $10 million, using an amendment to the 2025 state budget23. I do not have a verified cap table, so I cannot say what share of the company founders, staff or investors own. Expected dilution from the pending round is in my model, not in any source.

Valuation: is the last price supported?

Equity value in US$ billions. Not a share price: a private company has none. Latest mark: primary round, post-money (seed, reported by TechCrunch); a $40B+ pre-money round is under negotiation but not closed.

What the last valuation assumes

The $12B seed price assumed a team and a plan. The $40B+ pre-money in talks, about $45B to $46B after the money goes in16, assumes the company reaches something like my bull case: a frontier-grade model and several billion dollars of revenue within four years. On $100M to a few hundred million of annualised sales today, it is paying for the future almost entirely.

Bear, base and bull

CaseEquity value
Bear$1B
Base$12B
Bull$75B
Margin-of-safety value$9B
Last valuation (Jul 2025)$12B
  • Bear. Annualised revenue starts at $0.15B (low end of the press range, my estimate) and grows 80%, 50%, 30%, 20% to about $0.6B by 2030. Terminal enterprise value is 6x sales, below Snowflake’s 18.6x19. Discount rate 25%. Dilution 40% from needed raises. Equity about $0.9B, shown as 1.
  • Base. Starts at $0.3B (midpoint of press range, my estimate16). Growth of 150%, 100%, 70%, 50% gives about $3.8B revenue in 2030. Terminal 10x sales, a discount to Snowflake 18.6x and Nvidia 16.0x1920 because growth is slowing and margins are unproven. Discount rate 20%, my choice for a venture-stage company. Dilution 35%. Equity about $12.0B.
  • Bull. Starts at $0.5B. Growth of 250%, 150%, 100%, 70% gives about $14.9B in 2030, meaning a successful frontier model. Terminal 15x sales, near Nvidia’s 16.0x20 and well under Palantir’s 57x18. Discount rate 18%, dilution 35%. Equity about $75B.

Comparables used

CompanyMetricValueSource
PalantirEV / trailing sales57.4x18
SnowflakeEV / trailing sales18.6x19
NvidiaEV / trailing sales16.0x20

Where I come down

The last closed price, $12B, is near my base of about $12B. The talks at $40B or more are well above it: roughly three to four times my base and just over half of my bull. To justify $40B pre-money I would have to believe revenue reaches about $10B or more by 2030 and that the company stays independent and keeps its researchers. The market may still be right. Frontier AI has repeatedly produced revenue growth that models like mine did not allow for, and a lead investor with Nvidia on board can value compute access and strategic position, not just revenue. Nvidia also profits when its customer succeeds, which can make its investment less price-sensitive. I give the bull case only a modest chance. Margin of safety is my base less 25 percent, about $9B, and the talks are far above that. My model is sensitive: a one-turn change in the terminal multiple moves base value by about $1.2B, and a different starting revenue moves it in proportion.

What I cannot judge

I cannot see the company’s real revenue, costs, cash, cap table or the terms of the Nvidia investment. I cannot judge model quality beyond what the company and press say. I cannot say who pays for the gigawatt of compute. Treat my range of about $1B to $75B as wide on purpose. It is research, not investment advice.

The IPO

No IPO plan reported. I found no report of an IPO filing or plans as of 3 November 2026. The only SEC filing I found is a small Form D for a pooled fund45. The company is raising private capital instead16. Murati is reported to hold voting control16, which is typical of founders who stay private for a long time. No exchange, ticker, banks or timing are reported.

What to watch

  • Whether the $5B to $6B round closes, at what valuation, and who leads16
  • Any published revenue figure or audited accounts
  • Further cofounder or senior researcher exits
  • First deployment of Vera Rubin systems, targeted early 20271013
  • A closed frontier model, or Inkling adoption data
  • Any Form D or other SEC filing from the operating company

What could go wrong

What most likely destroys this business: spending on compute outrunning revenue. If the company must pay for the gigawatt commitment from its own funds, that is tens of billions of dollars against revenue that is at most a few hundred million1116. If it cannot keep raising, the commitments or the research would have to shrink.

What has to go right together. First, Tinker and Inkling revenue keeps growing quickly. Second, the company ships a model good enough to charge for at the frontier. Third, it keeps its key researchers. Fourth, it raises the capital for compute on acceptable terms. Fifth, no larger rival undercuts it. If I give each a rough 60 to 70 percent chance and treat them as loosely linked, the combined chance is nearer 10 to 20 percent. That is my estimate, not a measured figure. It is also why a venture investor can still do well: payoffs are lopsided, and one success can cover many failures.

Other risks: the funding talks might not close or might close lower, as the $50 billion talks did not14. Open-weight releases can be copied. Key staff keep leaving16. The next best alternative for the same dollar is a listed company with revenue you can read, such as Nvidia at 16 times sales20, or a larger AI lab if one becomes available, at least when you want filed accounts. I cannot say any of these is better. They are simply easier to check.

Sources

  1. 1Thinking Machines Lab: company site (opens in a new tab)Primary2026-11-03 · Accessed 6 Nov 2026↑
  2. 2Thinking Machines Lab: news index (opens in a new tab)Primary2026-11-03 · Accessed 6 Nov 2026↑
  3. 3Thinking Machines Lab: Tinker product page (pricing, models, customers) (opens in a new tab)Primary2026-11-03 · Accessed 6 Nov 2026↑
  4. 4SEC EDGAR: Form D, Thinking Machines Lab Jun 2025 a Series of CGF2021 LLC (opens in a new tab)Primary2025-06-27 · Accessed 6 Nov 2026↑
  5. 5SEC EDGAR: filing list for Thinking Machines Lab entities (opens in a new tab)Primary2026-11-03 · Accessed 6 Nov 2026↑
  6. 6eWeek: Sam Altman's Former CTO Launches OpenAI Competitor, Thinking Machine Labs (opens in a new tab)News2025-02-18 · Accessed 6 Nov 2026↑
  7. 7Reuters via Yahoo Finance: Murati's Thinking Machines seeks $50 billion valuation, Bloomberg reports (opens in a new tab)News2025-11-13 · Accessed 6 Nov 2026↑
  8. 8Bloomberg Law: Murati's Thinking Machines raises cash at $10 billion valuation (opens in a new tab)News2025-06-23 · Accessed 6 Nov 2026↑
  9. 9TechCrunch: Mira Murati's Thinking Machines Lab is worth $12B in seed round (opens in a new tab)News2025-07-15 · Accessed 6 Nov 2026↑
  10. 10TechCrunch: Thinking Machines Lab inks massive compute deal with Nvidia (opens in a new tab)News2026-03-10 · Accessed 6 Nov 2026↑
  11. 11The Next Web: Thinking Machines Lab secures Nvidia investment (opens in a new tab)News2026-03-11 · Accessed 6 Nov 2026↑
  12. 12The Daily Upside: Nvidia partnership reveals big ambitions for former OpenAI tech chief's startup (opens in a new tab)News2026-03-11 · Accessed 6 Nov 2026↑
  13. 13The Neuron: Murati's startup answers skeptics with a giant Nvidia deal (opens in a new tab)News2026-03-11 · Accessed 6 Nov 2026↑
  14. 14RuntimeWire: Thinking Machines seeks $1B-plus at a $40B valuation after last fall's $50B ask (opens in a new tab)News2026-10-14 · Accessed 6 Nov 2026↑
  15. 15Let's Data Science: Thinking Machines Lab pursues $5-6 billion funding round (opens in a new tab)News2026-09-04 · Accessed 6 Nov 2026
  16. 16The Next Web: Thinking Machines is in talks to raise $6bn, The Information reports (opens in a new tab)News2026-09-06 · Accessed 6 Nov 2026↑
  17. 17PYMNTS: Thinking Machines Lab seeks $1 billion at $40 billion valuation (opens in a new tab)News2026-09-03 · Accessed 6 Nov 2026↑
  18. 18StockAnalysis: Palantir statistics (opens in a new tab)Data2026-11-03 · Accessed 6 Nov 2026↑
  19. 19StockAnalysis: Snowflake statistics (opens in a new tab)Data2026-11-03 · Accessed 6 Nov 2026↑
  20. 20StockAnalysis: Nvidia statistics (opens in a new tab)Data2026-11-03 · Accessed 6 Nov 2026↑
  21. 21Thinking Machines Lab: Thinking Machines Lab and NVIDIA announce long-term gigawatt-scale strategic partnership (opens in a new tab)Primary2026-03-10 · Accessed 6 Nov 2026↑
  22. 22Thinking Machines Lab: Inkling, our open-weights model (opens in a new tab)Primary2026-07-15 · Accessed 6 Nov 2026↑
  23. 23RTSH: Albania Enters Global AI Market; Government Invests $10 Million in 'Machine Thinking Lab' Led by Albanian-American Mira Murati (opens in a new tab)News2025-05-01 · Accessed 6 Nov 2026↑

Research, not investment advice. Private company: figures are from funding rounds, filings and press reports as of 2026-11-06.

Legal information and disclosures

These are my own views as of the update shown on this page. They can change without notice, and I have no duty to update them. Past performance does not indicate future results, and any investment can lose money.

This is for education only. It is not investment, legal, tax or accounting advice, and it is not an offer to sell or a solicitation to buy any security in any jurisdiction. It does not consider your goals or circumstances. Shares in private companies are generally not available to the public.

Figures from company filings and other third parties are believed to be reliable, but I have not independently verified them and cannot guarantee them. Valuations of private companies are reported by the press or set by funding rounds and may not reflect what shares would sell for. Bear, base and bull values, and anything marked as an estimate, are my own and rest on assumptions that may prove wrong.

Please do not copy or republish this material without my written consent.