Baseten announced a $1.5 billion Series F financing round led by Altimeter Capital, Conviction Partners, and Spark Capital, with co-leads Sands Capital and Wellington Management. The round values the company at $13 billion and includes investments made across two tranches at $13 billion and $11 billion respectively.

The company reported 20x year-over-year revenue growth and stated that inference volume grew 40x, with the platform handling more than 1 billion inference calls daily across 87 clusters and 18 clouds. Additional investors in the round include IVP, Greylock, 01A, Battery Ventures, D. E. Shaw Ventures, Durable Capital Partners, and Verified Capital, among others.

Baseten positions itself as a multi-model inference and post-training platform that helps customers combine frontier models with custom models optimized on proprietary data. The company emphasizes latency, reliability, observability, and cost when serving models at scale, operating as a cross-cloud inference layer rather than a single-cloud service.

The new capital will fund compute, software, and talent investments to support the company's multi-model inference and post-training services. "The future of AI will be built on millions of specialized models, and the companies building the best ones know that post-training has become existential," said Tuhin Srivastava, Baseten's CEO and co-founder.

Named customers using post-training and custom models on the Baseten platform include Cursor, Notion, Harvey, and HubSpot.