Goodfire

Goodfire is an AI interpretability research company building tools to understand, debug, and intentionally design AI models. Its flagship platform, Ember, decodes the internal representations of neural networks — mapping model neurons to human-readable concepts — enabling developers and researchers to inspect model internals, shape model behaviour, and improve performance without retraining from scratch. Customers include Microsoft, the Mayo Clinic, and the Arc Institute. Founded in 2023, Goodfire raised a $150M Series B led by B Capital in February 2026, bringing total funding to $209M at a $1.25B valuation.