TL;DR: Goodfire raised $150M Series B at $1.25B valuation to build AI interpretability tools. They’ve reduced hallucinations by 50% and discovered Alzheimer’s biomarkers by understanding what’s happening inside AI models. Customers include Arc Institute, Mayo Clinic, and Microsoft.
The Numbers
| Metric | Value |
|---|---|
| Series B | $150 million |
| Valuation | $1.25 billion |
| Lead Investor | B Capital |
| Hallucination Reduction | 50% |
| Key Customers | Arc Institute, Mayo Clinic, Microsoft |
Why This Matters
Every frontier AI model is a black box. Foundation models are now:
- Writing significant amounts of production code
- Running loose on the internet
- Integrated into military systems
Yet we don’t understand how they make decisions. Goodfire’s thesis: we need to “open the black box” to build models that are powerful but also steerable and safe.
Real Results
Goodfire isn’t just doing research. They’ve delivered concrete outcomes:
- Reduced hallucinations by 50% using interpretability-informed training
- Identified novel Alzheimer’s biomarkers by reverse-engineering a biological model
- Built production monitoring tools for enterprise customers
The Technology
Their “model design environment” provides:
- Interpretability-based primitives for insights
- Tools to improve model behavior
- Production monitoring capabilities
- Shared collaboration with customers
Customer Quote
“Interpretability, for us, is the toolset for a new domain of science: a way to form hypotheses, run experiments, and ultimately design intelligence rather than stumbling into it.”
— Eric Ho, CEO of Goodfire
The Investors
- B Capital (lead)
- Juniper Ventures
- DFJ Growth
- Salesforce Ventures
- Menlo Ventures
- Lightspeed Venture Partners
- South Park Commons
- Wing Venture Capital
- Eric Schmidt
FAQ
What does Goodfire do? Goodfire builds interpretability tools that let you understand and edit what’s happening inside AI models.
How much is Goodfire worth? $1.25 billion after the Series B.
What results has Goodfire achieved? They reduced hallucinations by 50% and identified novel Alzheimer’s biomarkers.
Who uses Goodfire? Arc Institute, Mayo Clinic, and Microsoft are customers.
Who invested in Goodfire? B Capital led the round, with participation from Salesforce Ventures, Lightspeed, Menlo Ventures, and Eric Schmidt.
Last verified: March 1, 2026
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