Fireworks AI, the startup that runs open-source AI models for other companies, is in talks for a new funding round that would value it at $15 billion, according to Bloomberg. That is almost four times the $4 billion valuation it set in its October 2025 Series C, with earlier backer Index Ventures said to be co-leading the new deal.
Founded in 2022 by former Meta engineer Lin Qiao, Fireworks specializes in high-efficiency inference for open-source large language models. The company processes well over 10 trillion tokens per day and counts Cursor, Perplexity, Notion and Uber among its customers, having reached roughly $315 million in annualized revenue in February, up about 416% year over year.
The near-quadrupling in seven months is a fresh test of how far investor appetite for AI infrastructure can run. The round has not closed and terms could still change.