Langfuse

Open-source LLM observability and engineering platform for tracing, evaluation, and prompt management

LightOn

Sovereign enterprise GenAI platform deployed on-prem, air-gapped, or EU cloud

Langfuse

Excellent

22/25

LightOn

Excellent

22/25

Score Breakdown

DimensionLangfuseLightOn

Data Residency

Where is your data stored and processed?

Langfuse: EU cloud region (Ireland) keeps data within EEA. Full self-hosting option allows air-gapped EU deployments with zero cloud dependency. Customer can choose exact data location.

LightOn: Deploys on-premise, in customer VPC, or air-gapped on EU infrastructure, so data never leaves the customer's own security perimeter. Strongest possible residency posture.

5/5

EU cloud region (Ireland) keeps data within EEA. Full self-hosting option allows air-gapped EU deployments with zero cloud dependency. Customer can choose exact data location.

5/5

Deploys on-premise, in customer VPC, or air-gapped on EU infrastructure, so data never leaves the customer's own security perimeter. Strongest possible residency posture.

Legal Jurisdiction

Which laws govern the company and your data?

Langfuse: German GmbH (EU company) but acquired by ClickHouse Inc. (US). German law governs the entity but US parent introduces CLOUD Act considerations. Self-hosted deployment eliminates US cloud dependency.

LightOn: French SA incorporated in France, listed on Euronext Growth Paris, with no US parent. Fully under EU/French jurisdiction.

3/5

German GmbH (EU company) but acquired by ClickHouse Inc. (US). German law governs the entity but US parent introduces CLOUD Act considerations. Self-hosted deployment eliminates US cloud dependency.

5/5

French SA incorporated in France, listed on Euronext Growth Paris, with no US parent. Fully under EU/French jurisdiction.

Data Retention & Training

Is your data used for model training?

Langfuse: Explicitly does not train on customer data. Customer traces and prompts processed solely to provide the service. Self-hosted gives full data lifecycle control.

LightOn: In-perimeter deployment means no customer data is sent out or used to train shared models, and retention is governed by the customer's own infrastructure. Scored 4 rather than 5 as public DPA/retention-control documentation is limited.

5/5

Explicitly does not train on customer data. Customer traces and prompts processed solely to provide the service. Self-hosted gives full data lifecycle control.

4/5

In-perimeter deployment means no customer data is sent out or used to train shared models, and retention is governed by the customer's own infrastructure. Scored 4 rather than 5 as public DPA/retention-control documentation is limited.

Certifications

ISO 27001, SOC 2, Cyber Essentials, etc.

Langfuse: SOC 2 Type II and ISO 27001 certified with annual audits. HIPAA BAA available. Annual external penetration tests. Excellent certification posture for a developer tooling company.

LightOn: Holds SOC 2 Type 1. ISO 27001 and SOC 2 Type II are not confirmed in published sources, and ANSSI SecNumCloud appears to be a positioning goal rather than a confirmed qualification.

5/5

SOC 2 Type II and ISO 27001 certified with annual audits. HIPAA BAA available. Annual external penetration tests. Excellent certification posture for a developer tooling company.

3/5

Holds SOC 2 Type 1. ISO 27001 and SOC 2 Type II are not confirmed in published sources, and ANSSI SecNumCloud appears to be a positioning goal rather than a confirmed qualification.

Regulatory Fit

Suitability for regulated industries and professional services

Langfuse: EU data hosting, GDPR DPA, German legal origin, self-hosting for regulated industries. HIPAA compliance extends reach to healthcare. The ClickHouse acquisition is the main caveat for sovereignty purists.

LightOn: Purpose-built for regulated and sovereign EU buyers, with public-sector and defense/aerospace references (CNES, Safran, French tax authority) and GDPR/AI Act alignment.

4/5

EU data hosting, GDPR DPA, German legal origin, self-hosting for regulated industries. HIPAA compliance extends reach to healthcare. The ClickHouse acquisition is the main caveat for sovereignty purists.

5/5

Purpose-built for regulated and sovereign EU buyers, with public-sector and defense/aerospace references (CNES, Safran, French tax authority) and GDPR/AI Act alignment.

Total Score

22/25

Best For

Langfuse

Best for regulated industries (BaFin, CNIL); privacy-conscious teams who need strong data retention controls; organisations that need self-hosted or on-premise deployment; teams on a tight budget.

LightOn

Best for EU-headquartered organisations needing maximum data sovereignty; regulated industries (CNIL, AMF); privacy-conscious teams who need strong data retention controls; organisations that need self-hosted or on-premise deployment.

Detailed Comparison

Langfuse vs LightOn: Trust & Compliance Comparison

Langfuse (Langfuse (ClickHouse), DE) scores 22/25 overall with a Gold (Excellent) trust badge. Open-source LLM observability and engineering platform for tracing, evaluation, and prompt management. LightOn (LightOn, FR) scores 22/25 with a Gold (Excellent) trust badge. Sovereign enterprise GenAI platform deployed on-prem, air-gapped, or EU cloud.

Dimension-by-Dimension Breakdown

#### Data Residency

Both score equally at 5/5.

●Langfuse (5/5): EU cloud region (Ireland) keeps data within EEA. Full self-hosting option allows air-gapped EU deployments with zero cloud dependency. Customer can choose exact data location.

●LightOn (5/5): Deploys on-premise, in customer VPC, or air-gapped on EU infrastructure, so data never leaves the customer's own security perimeter. Strongest possible residency posture.

#### Legal Jurisdiction

LightOn leads with 5/5 vs 3/5.

●Langfuse (3/5): German GmbH (EU company) but acquired by ClickHouse Inc. (US). German law governs the entity but US parent introduces CLOUD Act considerations. Self-hosted deployment eliminates US cloud dependency.

●LightOn (5/5): French SA incorporated in France, listed on Euronext Growth Paris, with no US parent. Fully under EU/French jurisdiction.

#### Data Retention & Training

Langfuse leads with 5/5 vs 4/5.

●Langfuse (5/5): Explicitly does not train on customer data. Customer traces and prompts processed solely to provide the service. Self-hosted gives full data lifecycle control.

●LightOn (4/5): In-perimeter deployment means no customer data is sent out or used to train shared models, and retention is governed by the customer's own infrastructure. Scored 4 rather than 5 as public DPA/retention-control documentation is limited.

#### Certifications

Langfuse leads with 5/5 vs 3/5.

●Langfuse (5/5): SOC 2 Type II and ISO 27001 certified with annual audits. HIPAA BAA available. Annual external penetration tests. Excellent certification posture for a developer tooling company.

●LightOn (3/5): Holds SOC 2 Type 1. ISO 27001 and SOC 2 Type II are not confirmed in published sources, and ANSSI SecNumCloud appears to be a positioning goal rather than a confirmed qualification.

#### Regulatory Fit

LightOn leads with 5/5 vs 4/5.

●Langfuse (4/5): EU data hosting, GDPR DPA, German legal origin, self-hosting for regulated industries. HIPAA compliance extends reach to healthcare. The ClickHouse acquisition is the main caveat for sovereignty purists.

●LightOn (5/5): Purpose-built for regulated and sovereign EU buyers, with public-sector and defense/aerospace references (CNES, Safran, French tax authority) and GDPR/AI Act alignment.

Certifications at a Glance

Certification	Langfuse	LightOn
ISO 27001	Yes	No
SOC 2 Type 1	No	Yes
SOC 2 Type II	Yes	No

Overall Verdict

Langfuse and LightOn are closely matched on trust and compliance, with scores of 22/25 and 22/25 respectively. The right choice depends on your specific regulatory requirements and existing technology stack.

Frequently Asked Questions

Which is better for EU compliance, Langfuse or LightOn?

Langfuse has a TrustKit score of 22/25 while LightOn scores 22/25. Both tools are currently rated equally across data residency, legal jurisdiction, data retention, certifications, and regulatory fit.

How do Langfuse and LightOn compare on data residency?

Langfuse scores 5/5 for data residency (EU cloud region (Ireland) keeps data within EEA. Full self-hosting option allows air-gapped EU deployments with zero cloud dependency. Customer can choose exact data location.), while LightOn scores 5/5 (Deploys on-premise, in customer VPC, or air-gapped on EU infrastructure, so data never leaves the customer's own security perimeter. Strongest possible residency posture.).

Are Langfuse and LightOn GDPR compliant?

Both tools are assessed across five compliance dimensions. Langfuse has a regulatory fit score of 4/5 and LightOn scores 5/5. Check the full comparison above for a detailed breakdown.

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