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Diligence

Vendor Lock-In Is the Technical Risk Most Angels Miss

Kenneth Lo

The AI company you are evaluating probably depends on at least one vendor it cannot easily leave.

That is not automatically a problem.

But it is always worth understanding before you wire.

Vendor risk tends to look harmless at the demo stage because the product still works, the team moves quickly, and the dependency feels like a practical shortcut. What matters is how that shortcut behaves once pricing changes, model access shifts, or the company tries to scale without full control over the critical path.

How Vendor Risk Usually Shows Up

  1. API dependency without a switching plan

If the core product is built on a single model provider’s API — OpenAI, Anthropic, Google, or another upstream dependency — what happens when that provider changes pricing, deprecates a model version, or goes down?

We have seen all three over the last 18 months.

Companies with no abstraction layer between the product and the API take the full hit. Companies that built a thin routing or orchestration layer usually have more options and recover faster.

The question is not whether the company uses external models. Almost all of them do.

The real questions are:

  • how exposed is the product to one vendor’s decisions
  • how hard would it be to reroute requests elsewhere
  • how much product behavior breaks if the vendor changes terms
  • whether the team has already thought through that failure mode

Dependency becomes risk when there is no practical exit path.

  1. Data that lives in someone else’s system

If the company’s key asset — user data, training data, or proprietary signals — sits inside a vendor-controlled system with weak export capability, that is a moat problem disguised as a tooling choice.

The data is often the value.

If the company cannot move it, govern it, or reliably reconstruct it elsewhere, then the company does not fully control one of the most important inputs to its future defensibility.

This tends to show up in a few forms:

  • vendor-native storage with weak portability
  • workflows that depend on hosted labeling or enrichment systems
  • analytics and product feedback loops that are hard to extract
  • proprietary signals captured in formats the company does not fully own

A lot of teams call this speed. Sometimes it is. But speed bought at the cost of data control is still a strategic tradeoff, and investors should price it that way.

  1. Infrastructure cost that scales faster than revenue

Early AI companies routinely underestimate compute cost at scale.

When inference cost is not modeled against unit economics from day one, the gross margin problem often appears much later, usually at the moment the company wants to look efficient for the next round.

This is where vendor dependence quietly becomes a financing issue.

If product usage grows but:

  • model costs rise faster than pricing power
  • margin compression is hidden by early-stage growth
  • infrastructure assumptions were never pressure-tested
  • the team has no clear path to lower-cost serving

then the company may be building itself into a structural economics problem.

That is not just an ops issue. It can change valuation, capital needs, and the amount of strategic flexibility left in the business.

Why This Matters in Diligence

None of this is automatically disqualifying.

But it does change the conversation.

It changes valuation. It changes terms. It changes the downside map. And it changes the questions you should ask in the debrief.

That is why vendor lock-in, data control, and dependency exposure belong in technical diligence. Not because every dependency is bad, but because investors need to know which ones are manageable and which ones quietly control the future of the company.

Technical Due Diligence

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