LangChain raises US$300 million at a US$3 billion valuation, led by CapitalG

LangChain says it has raised US$300 million at a US$3 billion valuation, in a round led by existing investor CapitalG. Harrison Chase, LangChain’s co-founder and chief executive, announced the Series C in a blog post on 13 November, US time.

Chase said in a post on X that LangChain is building LangSmith, “the framework-agnostic platform to run, improve, and govern agents”. LangSmith is the company’s commercial platform for testing, running and monitoring AI agents, the programs that take actions on a user’s behalf.

Today we announced that LangChain raised $300M at a $3B valuation.

We think agents will transform the economy, and the companies that own their intelligence will build lasting competitive advantages.

That’s why we’re building LangSmith, the framework-agnostic platform to run, improve, and govern agents.

Still so much left to build! More on what’s next: https://t.co/uKMdmA9IkR

— Harrison Chase (@hwchase17) November 13, 2026

The Wall Street Journal reported the round on 12 November, a day before the announcement. LangChain’s previous round, announced on 20 October 2025, raised US$125 million at a US$1.25 billion valuation, so the new price is 2.4 times the old one. LangChain’s press release puts its total funding at US$460 million.

Who’s in the round

CapitalG, Alphabet’s growth fund, first invested in LangChain’s Series B. LangChain says the Series C drew “significant participation” from new investors GIC and DFJ Growth and existing investors IVP and Sapphire Ventures. The blog post also welcomes Salesforce Ventures, Insight Venture Partners, QuantumLight and MongoDB Ventures as new investors, and thanks Sequoia, Amplify and Benchmark for “doubling down”.

Dealroom’s write-up lists OpenAI, Anthropic, Amazon and Microsoft as competitors building their own agent infrastructure. It quotes CapitalG partner Mo Jomaa saying each of them “is trying to lock you into their ecosystem, lock you into their models, lock you into their infrastructure”, and that LangChain’s pitch is staying independent.

What LangSmith covers

LangChain says more than 7,000 organisations use LangSmith, among them Harvey, Rippling, Listen Labs, NVIDIA, Toyota and Salesforce. It says Clay uses it to monitor hundreds of millions of agent runs a month, and that Workday uses it to run and govern agents, cutting the time to deploy a new agent from five months to under a day. Both figures come from LangChain, not from the customers.

The blog post sorts LangSmith into three pillars: Agent Runtime, Agent Improvement and Agent Governance. Governance covers the LLM and Tool Gateways, which LangChain says manage model budgets and fallbacks, protect sensitive data, and control which tools agents can use and how they authenticate.

The open-source numbers

CapitalG’s own post says LangChain’s open-source projects have passed 1 billion downloads and now see more than 350 million a month. At the Series B, CapitalG says, the two core packages, LangChain and LangGraph, had about 90 million monthly downloads combined. The new figure also counts Deep Agents, LangChain’s open-source harness for long-running agents, so it isn’t a like-for-like comparison.

What the announcement doesn’t give

LangChain’s blog post gives no revenue figure and doesn’t break down how it will spend the money. SiliconANGLE reports that LangChain plans to nearly double its headcount to 850 by the end of 2027, hiring infrastructure experts, AI engineers, salespeople and marketers.

Next up is a release event on Friday 20 November, where LangChain says it will show several new LangSmith capabilities.