Arena Raises $200M Series B at $3.1B Valuation, Tops $100M ARR
pxd · x · 2026-10-09
AI evaluation platform Arena announced a $200 million Series B at a $3.1 billion valuation, with Felicis leading. Key numbers:
- Annualized revenue has surpassed $100 million
- 350 million sessions and 62 million votes facilitated to date
- Launched a new Alignment Index measuring whether AI agents behave safely, truthfully, and within user intent
Felicis argues that as AI agents take real actions, measuring capability alone is no longer enough — trustworthiness measurement is the next frontier.
Related event: LMArena Raises $200M Series B at $3.1B Valuation, Launches Alignment Index(9 posts)→
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