Baseten raised $1.5 billion in a Series F round at a valuation of up to $13 billion, announced on June 22, 2026 and led by Altimeter Capital, Conviction and Spark Capital. It's the company's fourth fundraise in 18 months, and it lands as inference — actually running AI models in production — becomes one of the most fiercely contested layers in AI infrastructure.
Here's the full breakdown of the raise, who backed it, and what it means for the inference market.
What is Baseten?
Baseten is an inference and post-training platform for AI models. Founded in 2019 in San Francisco by Tuhin Srivastava, Amir Haghighat, Pankaj Gupta and Philip Howes, the company helps enterprises deploy custom AI models in production with what it describes as "exceptional latency, reliability, observability, and cost at production scale."
In plain terms: building or fine-tuning an AI model is one problem, but serving it reliably to millions of real users — fast, cheap, and without falling over — is a separate, harder engineering problem. Baseten sells the infrastructure that solves the second part. Its customers include Cursor, Notion, Lovable, Harvey, HubSpot, OpenEvidence, Abridge and Decagon.
The raise: $1.5B Series F
The headline numbers:
- Amount: $1.5 billion
- Round: Series F
- Valuation: up to $13 billion, split across two tranches priced at $13 billion and $11 billion
- Announced: June 22, 2026
- Lead investors: Altimeter Capital, Conviction, Spark Capital
- Co-leads: Sands Capital, Wellington Management
The tranche structure — part of the round priced at $13 billion, part at $11 billion — reflects how the raise came together in stages as different investors committed at different times, rather than a single clean valuation.
For context, Baseten's previous round was a $300 million Series E at a $5 billion valuation in January 2026 — which itself followed a $150 million Series D at a $2.15 billion valuation just months before that. Going from $5 billion to as much as $13 billion in five months is roughly a 160% jump, one of the steepest valuation climbs of any AI infrastructure company in 2026.
Who invested in Baseten?
The Series F was led by Altimeter Capital, Conviction and Spark Capital, with Sands Capital and Wellington Management co-leading. Additional participants included:
- Battery Ventures
- Blackbird
- D.E. Shaw Ventures
- Durable Capital Partners
- Greylock
- IVP
- Verified Capital
- 01A
IVP had also co-led Baseten's Series E, alongside Nvidia and CapitalG — so this round brings in a wider mix of growth-stage and public-market crossover investors (Wellington, D.E. Shaw Ventures, Sands Capital) on top of the existing venture backers.
What Baseten will do with the money
Baseten said the financing will fund aggressive investment in compute infrastructure, software development and talent recruitment to keep pace with customer demand for deploying AI models in production.
The scale of that demand is the real story. The company says its inference volume has grown 40x and revenue has grown roughly 20x over the past year. That kind of growth curve is expensive to serve — more GPU capacity, more engineering to keep latency and reliability high, and more people to support enterprise customers integrating models into live products.
Why it matters
Baseten's round is a clean signal of where AI infrastructure spending is heading in 2026:
- Inference is eating the spotlight from training. Baseten's entire pitch is about serving models in production, not building them — and investors are pricing that layer at a premium as more companies move from AI pilots to shipped products.
- Valuations are compounding fast for infrastructure winners. Four fundraises in 18 months, with the valuation roughly 6x-ing over that span, shows how quickly capital is chasing companies that can prove real usage growth rather than just promise.
- The inference market has multiple well-funded players. Baseten's raise follows a similar pattern to Together AI's $800M Series C — both are independent infrastructure companies scaling fast to serve AI workloads outside the hyperscalers, and both are attracting investors who want exposure to the "picks and shovels" layer of AI rather than the model makers themselves.
For anyone tracking where AI funding is concentrating in 2026, Baseten is another marker that the money is flowing into the infrastructure that makes AI actually usable at scale — not just the models themselves.
Source: Baseten — Announcing our Series F
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