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  1. Core concepts

EU Data Sovereignty

HMS Sovereign operates a fully EU-owned and EU-hosted voice AI stack. All data processing infrastructure -- servers, database, voice AI orchestration, and speech models -- runs on Hetzner dedicated servers in Germany, owned and operated by a German company. When paired with EU-based AI providers (Gladia for STT, Mistral for LLM), the entire data processing pipeline is sovereign: EU-owned, EU-hosted, EU-operated.
Full EU Sovereignty - Every component that processes your data is owned by EU companies and hosted on EU soil. No US entity has access to your voice data, transcripts, call recordings, or AI conversations.

Infrastructure & Hosting#

All data processing infrastructure runs on Hetzner dedicated servers in Germany. Hetzner Online GmbH is a German company headquartered in Gunzenhausen, Germany -- fully EU-owned with no US parent company. This means:
Data residency: All data is stored and processed exclusively within the EU (Germany)
Corporate sovereignty: Hetzner is a German GmbH, not subject to the US CLOUD Act
Physical security: Hetzner data centers are located in Germany and Finland, subject to German and EU data protection law
Self-hosted database: The database runs self-hosted on Hetzner -- no third-party database provider involved
Self-hosted orchestration: The voice AI agent orchestrator runs on Hetzner -- all call processing stays on EU-owned infrastructure

The EU Data Processing Stack#

Every entity that touches your data is EU-incorporated and EU-hosted:
ComponentProviderServer LocationProvider HQLegal Entity
Platform & OrchestrationHMS SovereignGermany (Hetzner)NetherlandsDutch BV
DatabaseHMS Sovereign (self-hosted)Germany (Hetzner)NetherlandsDutch BV
Speech-to-TextGladiaEU-West (France)FranceFrench SAS
Language ModelMistralEuropeFranceFrench SAS
Text-to-SpeechHMS Sovereign (own models)Germany (Hetzner)NetherlandsDutch BV
InfrastructureHetznerGermanyGermanyGerman GmbH

HMS Sovereign (Platform, Orchestration & TTS)#

Dutch BV headquartered in the Netherlands. All application logic, voice AI orchestration, database, and proprietary TTS models run on Hetzner servers in Germany.

Hetzner (Infrastructure)#

German GmbH headquartered in Gunzenhausen, Germany. Data centers in Nuremberg, Falkenstein, and Helsinki. Fully EU-owned with no US parent company or investors subject to the US CLOUD Act.

Gladia (Speech-to-Text)#

French SAS headquartered in Paris. EU-West region for GDPR compliance.

Mistral (Language Model)#

French SAS headquartered in Paris. Models trained and hosted in Europe.

Data Flow#

Voice data never leaves the European Union. The entire voice AI pipeline (STT, LLM, TTS) stays within EU borders on EU-owned infrastructure -- Hetzner in Germany, Gladia and Mistral in France.

Setup Guide#

Step 1: Add Gladia API Key#

Navigate to Integrations in your HMS Sovereign dashboard, or add via API:
Get your Gladia API key at gladia.io

Step 2: Add Mistral API Key#

Add your Mistral API key for EU-based language model processing:
Get your Mistral API key at mistral.ai

Step 3: Configure Your Agent#

Create or update your agent with the EU-only configuration:

Step 4: Verify Configuration#

Your voice AI calls are now fully EU-sovereign. Test by making a call to your agent's phone number.

Provider Details#

Gladia (Speech-to-Text)#

Company: Gladia SAS (French Societe par Actions Simplifiee)
Headquarters: Paris, France
Features:
EU-West region for GDPR-compliant processing
90+ languages supported
Code switching (automatic language detection mid-conversation)
Real-time translation capabilities
Custom vocabulary support
Recommended Settings:
{
  "provider": "gladia",
  "model": "solaria-1",
  "region": "eu-west",
  "code_switching": true
}

Mistral (Language Model)#

Company: Mistral AI SAS (French Societe par Actions Simplifiee)
Headquarters: Paris, France
Available Models:
ModelUse CaseSpeed
mistral-small-latestFast responsesFastest
mistral-medium-latestBalanced (recommended)Medium
mistral-large-latestMost capableSlower
ministral-8b-2410LightweightFast
codestral-latestCode-focused tasksMedium
Pricing: 5-10x more cost-effective than US alternatives

HMS Sovereign TTS (Text-to-Speech)#

Operated by: HMS Sovereign (Flireo B.V.)
Headquarters: Netherlands
Infrastructure: Hetzner dedicated servers, Germany
Features:
Proprietary speech model hosted entirely on HMS Sovereign's own Hetzner servers
No external API calls for voice synthesis -- zero third-party data exposure
Low latency voice generation
Multiple voice options available
HMS Sovereign's own TTS models run directly on Hetzner servers in Germany. Voice synthesis never leaves EU-owned infrastructure, ensuring complete control over the final audio output.

Compliance#

GDPR Compliant#

Every entity that processes your data is an EU company subject to EU data protection laws: HMS Sovereign (Dutch BV), Hetzner (German GmbH), Gladia (French SAS), and Mistral (French SAS). Data is processed and stored exclusively within the EU.

Data Residency#

All voice processing occurs within EU borders (Germany and France). The database runs self-hosted on Hetzner in Germany. No voice data, transcripts, or AI conversations are transferred outside of the European Union at any point.

Schrems II#

No transatlantic data transfers required. All data stays within the EU on EU-owned infrastructure, eliminating legal uncertainty from EU-US data flows.

US CLOUD Act#

The entire data processing stack -- HMS Sovereign, Hetzner, Gladia, and Mistral -- consists of EU-incorporated companies that are not subject to the US CLOUD Act. No US entity has access to voice data, call recordings, transcripts, or AI conversations.

Comparison: US vs EU Stack vs On-Premise#

AspectFully US-BasedHMS Sovereign (EU Stack)On-Premise / Blackbox
Voice data leaves EUYesNoNo
Subject to US CLOUD ActYesNoNo
GDPR-native AI providersPartialFullFull
Schrems II concernsYesNoneNone
Requires SCCsYesNoNo
EU-owned infrastructureNoYes (Hetzner)Yes
EU-owned databaseNoYes (self-hosted)Yes
Typical latency (EU users)HigherLowerLowest
Full corporate sovereigntyNoYesYes
Important for Regulated Industries
Organizations in healthcare, finance, government, and legal sectors often have strict data residency requirements. Our EU stack provides full data sovereignty for all voice AI data on EU-owned infrastructure. For air-gapped or fully on-premise deployments, see Enterprise On-Premise Solutions.

Legal Entities#

HMS Sovereign#

Legal Name: Flireo B.V.
Entity Type: Dutch Besloten Vennootschap (BV)
Jurisdiction: Netherlands
Role: Platform provider, voice AI orchestration, TTS, and self-hosted database
Data Processing: All platform data, voice orchestration, and TTS processed on Hetzner servers in Germany

Hetzner#

Legal Name: Hetzner Online GmbH
Entity Type: German Gesellschaft mit beschrankter Haftung (GmbH)
Jurisdiction: Germany
Role: Dedicated server infrastructure (compute, storage, networking)
Data Centers: Nuremberg, Falkenstein (Germany) and Helsinki (Finland)
CLOUD Act: Not subject -- fully EU-owned with no US parent company or investors

Gladia#

Legal Name: Gladia SAS
Entity Type: French Societe par Actions Simplifiee
Jurisdiction: France
Role: Speech-to-Text processing
Data Processing: Audio transcription in EU-West region (France)

Mistral AI#

Legal Name: Mistral AI SAS
Entity Type: French Societe par Actions Simplifiee
Jurisdiction: France
Role: Language Model inference
Data Processing: LLM inference on European infrastructure

FAQ#

Is my data ever processed outside the EU?
No. When using Gladia + Mistral + HMS Sovereign TTS, all data processing occurs exclusively within the European Union on EU-owned infrastructure. Servers are located on Hetzner in Germany and Gladia/Mistral in France.
Do I need Standard Contractual Clauses (SCCs)?
No. Data never leaves the EU, so SCCs for transatlantic data transfers are not required. This simplifies your legal compliance significantly.
What about the US CLOUD Act?
The entire data processing stack -- HMS Sovereign (Dutch BV), Hetzner (German GmbH), Gladia (French SAS), and Mistral (French SAS) -- consists of EU-incorporated companies not subject to the US CLOUD Act. No US entity processes or stores your data.
Can I mix EU and non-EU providers?
Yes, but you would reduce your data sovereignty posture. For example, you can use Deepgram (US) for STT or OpenAI (US) for LLM, but this means voice data will be processed by US companies. For maximum sovereignty, use Gladia + Mistral + HMS Sovereign TTS.
Is there a latency difference?
EU users typically experience lower latency with the EU stack since all processing happens geographically closer (Germany and France). For users outside Europe, latency may be slightly higher.
What if I need a fully air-gapped deployment?
We offer dedicated on-premise and blackbox deployment options. In this model, all hardware and software runs on infrastructure you own or control, with no involvement of any non-EU entity. Contact us for details.

Enterprise On-Premise Solutions#

For enterprise clients in highly regulated industries who require air-gapped or fully on-premise deployments, we offer blackbox deployment options.

Blackbox On-Premise Deployment#

A self-contained, turnkey appliance that runs the entire HMS Sovereign stack on your own hardware or in your own data center:
Complete isolation: No external network dependencies. The entire stack (platform, database, STT, LLM, TTS) runs on infrastructure you own and control.
Air-gapped capable: Can operate in fully air-gapped environments with no internet connectivity.
Your security perimeter: Fits within your existing physical security, network policies, and access controls.

What Is Included#

ComponentDetails
HMS Sovereign PlatformFull platform deployment on your infrastructure
DashboardSelf-hosted on your infrastructure
DatabaseSelf-hosted on your infrastructure
Speech-to-TextOn-premise STT models
Language ModelOn-premise LLM inference
Text-to-SpeechOn-premise TTS engine (HMS Sovereign's own models)
Management & MonitoringDashboard and tooling for operations

Compliance Guarantees#

Zero data egress: No data ever leaves your physical premises
Full CLOUD Act immunity: No US or non-EU entity is involved at any level
Schrems II irrelevant: No cross-border data transfers of any kind
Audit-ready: Full control over logging, monitoring, and access trails
Custom DPA: Tailored Data Processing Agreement to meet your specific regulatory requirements
Anything is possible. Whether you need a single rack in your own data center, a fully air-gapped deployment, or a custom hybrid architecture, we work with your security and compliance teams to deliver a solution that meets your exact requirements. No compromise.

Get Started#

Contact our enterprise team to discuss your on-premise requirements:
Email: support@hmsovereign.com
Subject: On-Premise / Blackbox Deployment Inquiry
Our team will work with your IT, security, and legal departments to scope and deliver a deployment tailored to your compliance needs.

Related Documentation#

BYOK Setup Guide - Learn how to add your own API keys for any provider
Agent Configuration - API reference for creating and configuring agents
For more information about our EU data sovereignty offering, contact us at support@hmsovereign.com or consult with your legal team regarding specific compliance requirements.
Last updated: February 2026
Modified at 2026-02-10 16:00:42
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