AI MARKET FIT

AI MARKET FIT

10 new businesses unlocked by Thinking Machines

10 Businesses Unlocked by Training Your Own AI Model

Guillermo Flor's avatar
Guillermo Flor
Jul 19, 2026
∙ Paid

Most AI products being launched today rent intelligence from the same handful of GPT and Claude APIs. That makes them fast to build, but it also leaves them with similar capabilities, permanently variable costs and limited control over the technology at the centre of their product.

This week, Mira Murati’s Thinking Machines released Inkling, a 975B open-weights model that companies can fine-tune through its Tinker platform without building their own GPU infrastructure. Bridgewater has already used the platform to train an open model on its financial knowledge and reportedly outperform proprietary models on financial reasoning.

Fine-tuning is becoming accessible enough for startups to own the intelligence they sell. Founders can now build specialized models, license them, deploy them inside enterprise environments and create businesses that were previously reserved for well-funded AI labs.

In this issue, I break down:

  1. How owning the model can give startups better margins, control and defensibility

  2. Why open weights turn AI intelligence into an asset your company can own

  3. How startups can now train specialized models without becoming AI labs

  4. Why Inkling’s capabilities matter for products, customers and unit economics

  5. 10 business ideas unlocked by accessible fine-tuning

  6. How to decide whether owning a model should become your startup’s advantage

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1.How owning the model can give startups better margins, control and defensibility

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