LangChain, the San Francisco startup behind widely used open-source tools for building AI agents, has raised $300 million at a $3 billion valuation. The round was led by CapitalG, the growth fund of Alphabet, and the news came out on 12 November 2026.
IVP, Sapphire Ventures, the Singapore fund GIC and DFJ Growth also took part. The valuation is about 2.4 times the $1.25 billion set in October 2025, when LangChain raised $125 million in a round led by IVP that CapitalG and Sapphire joined. Revenue was not disclosed.
Illustration MLQ ran with its funding report
Image: MLQ
Harrison Chase released the LangChain framework in 2022. It has since added LangGraph, for multi-agent workflows with human approval, and Deep Agents, which brings a virtual file system, planning and subagents. Its paid product, LangSmith, lets teams version and roll back agents, compare output quality and trace problems, with suggested code fixes. Autodesk and Cisco are named customers.
About LangChain
LangChain is a San Francisco startup that makes open-source tools for building AI agents, led by Harrison Chase. Its paid LangSmith suite is the product that brings in its revenue.
Chase released the LangChain framework in 2022 to connect large language models to tools and data, and LangGraph and Deep Agents followed. In October 2025 the company raised $125 million at a $1.25 billion valuation in a round led by IVP, which CapitalG and Sapphire also joined. After that round it said its open-source tools were downloaded about 90 million times a month and that Autodesk and Cisco used LangSmith.
After the last round the company said its open-source tools were downloaded about 90 million times a month. It plans to nearly double its headcount to about 850 by the end of 2027, hiring in infrastructure, AI engineering, sales and marketing. LangChain had made no statement of its own when the first reports appeared.
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