# Self-Hosted AI vs Microsoft Copilot for Legal

> Source: https://ibl.ai/resources/comparisons/self-hosted-ai-vs-microsoft-copilot-for-legal


*Own the models, data, and code behind your legal AI on your own infrastructure — vs. a per-seat assistant running in the Microsoft cloud*

Legal organizations adopting AI face one hard constraint before any feature: privileged client matters must stay protected under attorney-client privilege and ABA ethics duties. Where the AI runs — and who controls it — matters as much as what it does.

Microsoft Copilot is a managed assistant from Microsoft, billed at about $30 per user per month and running in the Microsoft cloud on Microsoft and OpenAI models. Its strength is deep Microsoft 365 integration with little setup, but it is tied to Microsoft 365 and OpenAI models and your data is processed in the vendor's cloud.

Self-hosted AI runs on infrastructure you control — on-premise, in your private cloud, or fully air-gapped. You own the code, the data, and the models, run any LLM, and keep privileged client matters inside your perimeter, integrated with Clio, iManage, NetDocuments, Westlaw, and LexisNexis. This comparison covers case research, contract review, discovery, and knowledge management for legal — and when each option is the right call.

## Feature Comparison

### Capabilities

| Criteria | Self-Hosted AI | Microsoft Copilot |
|----------|--------------------|--------------------|
| Out-of-the-Box Productivity | Strong agent capability once deployed; you configure the workflows your teams need. | Polished assistance from day one with deep Microsoft 365 integration. |
| Legal System Integration | Deep integration with Clio, iManage, NetDocuments, Westlaw, and LexisNexis via APIs and MCP, built around your data. | Connects to common tools, but integration with sector systems is limited. |
| Custom Agents & Workflows | Build and own production agents for case research, contract review, discovery, and knowledge management. | A few prebuilt agents; customization is bounded by the platform. |
| Any-LLM & Model Control | Run any open or commercial model, route by cost/latency/capability, and switch anytime. | Runs on Microsoft and OpenAI models; tied to Microsoft 365 and OpenAI models. |

### Ownership & Data Control

| Criteria | Self-Hosted AI | Microsoft Copilot |
|----------|--------------------|--------------------|
| Self-Hosting / On-Prem / Air-Gapped | Run on your servers, private cloud, or fully air-gapped with zero external calls. | Runs in the Microsoft cloud; cannot be self-hosted or air-gapped. |
| Data Stays in Your Perimeter | privileged client matters never leaves your environment; every interaction is logged for audit. | Vendor controls help, but data is processed in the provider's cloud. |
| Model Choice | Any LLM — open-source or commercial — under your control. | Locked to Microsoft and OpenAI models. |
| Source Code & Platform Ownership | Own the full platform code; no lock-in to a vendor's roadmap. | You rent access; the platform and roadmap belong to the vendor. |

### Cost & Compliance

| Criteria | Self-Hosted AI | Microsoft Copilot |
|----------|--------------------|--------------------|
| Cost at Scale | Flat, usage-based cost on owned compute — no per-seat fees. | about $30 per user per month; cost rises with every seat. |
| Compliance & Audit Fit | Data stays in your perimeter, supporting attorney-client privilege and ABA ethics duties with full audit logging. | Vendor compliance coverage under shared-responsibility cloud terms. |
| Time-to-Value | Requires infrastructure and setup, or a partner to deploy it for you. | Turn it on for your users with minimal setup. |
| Support & Maintenance | Self-managed, or fully supported with forward-deployed engineers. | Fully managed by Microsoft with enterprise support. |

## Detailed Analysis

### Legal Data Sovereignty vs Cloud Convenience

**Self-Hosted AI:** Self-hosted AI keeps privileged client matters inside your perimeter and can run fully air-gapped — the strongest posture for attorney-client privilege and ABA ethics duties.

**Microsoft Copilot:** Microsoft Copilot adds capable assistance quickly, but processes data in the Microsoft cloud under shared-responsibility terms.

**Verdict:** For legal workloads bound by attorney-client privilege and ABA ethics duties, owning the stack is the safer default; Copilot fits lower-sensitivity productivity.

### Per-Seat Cost vs Flat Ownership

**Self-Hosted AI:** Self-hosting replaces per-seat licensing with flat cost on compute you own, so broad rollouts don't scale with headcount.

**Microsoft Copilot:** Microsoft Copilot is about $30 per user per month, predictable per user but growing with every license.

**Verdict:** For organization-wide deployment, owned infrastructure is often far cheaper at scale.

### Model Freedom vs a Single Vendor

**Self-Hosted AI:** A model-agnostic platform runs any model — including the vendor's own — and switches as the frontier moves.

**Microsoft Copilot:** Microsoft Copilot is tied to Microsoft 365 and OpenAI models.

**Verdict:** If avoiding model lock-in matters, the owned, model-agnostic platform wins.

## FAQ

**Q: Is there a self-hosted, privilege-ready alternative to Microsoft Copilot for legal?**

Yes. A self-hosted, model-agnostic platform runs on infrastructure you control, keeping privileged client matters in your perimeter under attorney-client privilege and ABA ethics duties — while delivering AI agents for case research, contract review, discovery, and knowledge management without per-seat fees.

**Q: Can it run air-gapped, unlike Microsoft Copilot?**

Yes. It can run on-premise or fully air-gapped with local models and zero external calls. Microsoft Copilot is a cloud service in the Microsoft cloud and cannot be self-hosted or air-gapped.

**Q: Where does privileged client matters go with Copilot vs self-hosting?**

Microsoft Copilot processes data in the Microsoft cloud under shared-responsibility terms. With a self-hosted platform, privileged client matters stays entirely within your environment and every interaction is logged for audit.

**Q: Is self-hosted AI cheaper than Microsoft Copilot at scale?**

Usually, for large rollouts. Microsoft Copilot is about $30 per user per month, so cost grows with every seat. Self-hosting replaces that with flat, usage-based cost on compute you own.

**Q: Can I still use Microsoft and OpenAI models?**

Yes. A model-agnostic platform can route to Microsoft and OpenAI models alongside open and other commercial models — and switch anytime — rather than being tied to Microsoft 365 and OpenAI models.

**Q: How does ibl.ai fit in?**

ibl.ai is a model-agnostic, self-hosted AI platform you own and run on your own servers — on-premise or air-gapped — for case research, contract review, discovery, and knowledge management, while supporting attorney-client privilege and ABA ethics duties by design.