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LangChain

LangChain · Agent platform · US · www.langchain.com

Last verified 2026-09-16
Entry services/langchain.yaml
Training on your data (default tier)
Not stated in the privacy policy for traces and prompts logged to LangSmith; the platform terms and DPA govern customer data
Retention
As long as reasonably needed for the relationship, legal obligations and dispute protection
Data residency
Headquartered in and processing in the United States; an EU LangSmith region exists as a product option

Vendor data-handling terms

Training on your data (default tier)
Not stated in the privacy policy for traces and prompts logged to LangSmith; the platform terms and DPA govern customer data

LangSmith stores full traces, including prompts and completions, from instrumented applications. Whether that content is used to improve the platform is set by the customer terms, not the privacy policy. The open-source libraries send nothing to LangChain unless tracing is enabled.

“We provide a unified developer platform LangSmith for developing, collaborating, testing, deploying and monitoring LLM applications (the “ Services ”).”
checked 2026-09-16
LangChain Privacy Policy
Retention
As long as reasonably needed for the relationship, legal obligations and dispute protection
“We may retain your personal information for as long as it is reasonably needed in order to maintain and expand our relationship and provide you with our services; in order to comply with our legal and contractual obligations; or to protect ourselves from any potential disputes.”
checked 2026-09-16
LangChain Privacy Policy
Data residency
Headquartered in and processing in the United States; an EU LangSmith region exists as a product option
“We are headquartered in the United States. / To provide and operate our services, it is necessary for us to process your personal information in the United States.”
checked 2026-09-16
LangChain Privacy Policy

Domains and endpoints

observed means seen in Unseen deployments; vendor-documented means listed by the vendor. Vendors do not publish complete lists.

HostRoleSource
api.langchain.comapiobserved
smith.langchain.comappobserved

Assessment

LangSmith cloud: mediumOpen-source libraries without tracing: low

Reasoning: The libraries themselves send no data. LangSmith tracing ships every prompt and response from an application to LangChain's cloud, which is the exposure: developers often enable it with an environment variable and forget. US by default, EU region available, self-hosting on enterprise plans.

Flags: Tracing sends full prompts and completions to the vendor · US processing by default · Assessed 2026-09-16. The assessment is Unseen's; the terms above are the vendor's.

Changelog

  • 2026-09-16Documented. Scope, retention and location terms verified against the LangChain privacy policy.
  • 2026-09-15Listed from the Unseen catalogue with observed domains.

Corrections

Pull request on GitHub, or the form below. Changes are reviewed and recorded in the changelog.

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