Open-source LLM Observability: Langfuse Acquired by ClickHouse, Inc.

Deutsch: Orrick berät LLM-Monitoring-Start-up Langfuse bei Erwerb durch ClickHouse, Inc.

Langfuse, founded in 2023, and a leading open-source platform for LLM observability, evaluations, and prompt management, has been acquired by Bay Area headquartered ClickHouse, Inc.

Langfuse is one of the fastest growing LLM engineering platforms, with more than 2,000 paying customers, >2,000 GitHub stars, 26M+ SDK installs per month, and 6M+ Docker pulls, and is trusted by 19 of the Fortune 50 and 63 of the Fortune 500 companies.

Orrick represented Langfuse since its foundation and during this transaction.

THE COMPANIES

Langfuse is an open-source platform for building, testing, and monitoring LLM applications/agents. Teams use Langfuse to trace and debug agent workflows, run evaluations, and continuously measure and improve the quality of AI outputs in production. Langfuse is available as a managed cloud service and can be self-hosted at production scale. Langfuse was founded by Marc Klingen, Maximlian Deichmann and Clemens Rawert. The company previously raised capital from Y Combinator, Lightspeed Venture Partners and General Catalyst.

ClickHouse is a fast, open-source columnar database management system built for real-time data processing and analytics at scale. Engineered for high performance, ClickHouse Cloud delivers exceptional query speed and concurrency, making it ideal for applications that demand instant insight from massive volumes of data. As AI agents become increasingly embedded in software and are generating far more frequent and complex queries, ClickHouse brings a high-throughput, low-latency engine, purpose-built to meet this challenge. ClickHouse, Inc. was founded in 2021 and is backed by leading investors including Index Ventures, Lightspeed Venture Partners, Benchmark, Coatue, Bessemer Venture Partners and, Khosla Ventures; most recently, the company raised a Series D round at a $15 billion valuation led by Dragoneer Investment Group with participation from T. Rowe Price.

THE IMPACT

By combining Langfuse's developer-first approach to AI quality monitoring with ClickHouse's fast core analytical capabilities, a comprehensive, open-source stack for building, monitoring, and optimizing AI applications at scale can be offered.

"We built Langfuse on ClickHouse because LLM observability and evaluation is fundamentally a data problem," said Marc Klingen, CEO of Langfuse. "Now, as one team, we can deliver a tighter end-to-end product: faster ingestion, deeper evaluation, and a shorter path from a production issue to a measurable improvement."

THE TEAM

Sven Greulich and Mark Seneca led the international Orrick team from our Düsseldorf, Munich, Silicon Valley, San Francisco, New York, Santa Monica and Washington, D.C. offices which further included Sebastian Hummel, Brian Blood, Sky Stallbaumer, John Harrison, Onur Öztürk and John Bautista, supported by Stefan Schultes-Schnitzlein, Carsten Engelings, Peter Elias and SeoJung Park (tax), Sarah Schaedler, Jennifer Criss, Rachel Nghe and Benedikt Migdal (technology transactions), Michael Y. Yang, Sharon Zhou, André Zimmermann and Marianna Urban (compensation & benefits / employment), Lars Mesenbrink, Benedikt Kamann and Jeanine P. McGuinness (antitrust and international trade), Christian Schröder, Robert Weinhold and Shannon Yavorsky (cyber, privacy and data innovation).