How Copilot Accesses Your Data

The Graph connection — Copilot’s data pipeline

How Copilot processes a prompt

Step	What Happens	Who Controls It
1. User prompts	”What’s the latest on Project Phoenix?”	The user
2. Orchestration	Copilot’s orchestration service prepares the query	Microsoft (backend)
3. Graph query	Query sent to Microsoft Graph using the user’s access token	M365 permissions
4. Data retrieval	Graph returns relevant emails, files, chats, meetings — filtered by user’s permissions	SharePoint, Exchange, Teams permissions
5. Grounding	Retrieved data is combined with the user’s prompt and sent to the LLM	Microsoft (backend)
6. Response	LLM generates a response grounded in the user’s organisational data	Copilot

Key exam concept: At Step 4, the Graph ONLY returns data the user already has permission to access. This is called permission-trimmed access. If the user can’t see a SharePoint file directly, Copilot can’t use it either.

What Copilot CAN and CANNOT see

Copilot's access boundary = your access boundary

Feature	✅ Copilot CAN See	❌ Copilot CANNOT See
Your email
Files you have access to in SharePoint/OneDrive
Teams chats and channels you're a member of
Your calendar and meetings
Files in SharePoint sites you DON'T have access to
Other people's private OneDrive files
Private channels you're NOT a member of
Email from other people's mailboxes

Why this matters — the oversharing problem

Here’s the exam scenario that trips everyone up:

“After deploying Copilot, employees discover they can ask Copilot about documents they didn’t know existed but technically had access to.”

This is NOT a Copilot bug. It’s a permissions problem. Copilot didn’t grant them new access — it just made their EXISTING access more discoverable. The files were always accessible; Copilot just made them easier to find.

⚠️ The oversharing scenario — exam favourite

Northwave deploys Copilot. An intern asks: “Show me the latest board meeting notes.”

Before Copilot: The intern technically had read access to the Board SharePoint site (permissions were too broad), but never navigated there directly. No one noticed.

After Copilot: Copilot finds and summarises the board notes because the intern has permission. The CISO panics.

Root cause: SharePoint permissions were too broad — NOT a Copilot issue.

Fix:

1. Restrict SharePoint permissions on the Board site (break inheritance, owner-only access)
2. Run a SharePoint data access governance report to find other overshared sites
3. Apply sensitivity labels to board documents (add encryption for extra protection)

Exam answer: “Fix the permissions, not Copilot.”

How M365 controls protect Copilot

Control	How It Protects Copilot
SharePoint permissions	Copilot can only access files the user can access
Sensitivity labels	Labels restrict what can be done with content (encrypt, block external sharing)
DLP policies	Prevent Copilot-surfaced content from being shared inappropriately
Conditional Access	Control which devices/locations can use Copilot
Microsoft Defender	Monitor for suspicious AI-related activity
DSPM for AI	Visibility into how sensitive data interacts with Copilot

Web grounding vs Graph grounding

Mode	Data Source	Admin Control
Graph grounding	Your organisation’s M365 data (emails, files, chats)	Controlled by M365 permissions
Web grounding	Public internet via Bing	Can be DISABLED by admin in M365 admin center

Exam tip: Some organisations disable web grounding for compliance — they only want Copilot to use internal data. Admins can toggle this in the M365 admin center.

🎬 Video walkthrough

🎬 Video coming soon

How Copilot Accesses Data — AB-900 Module 16

How Copilot Accesses Data — AB-900 Module 16

~10 min

Flashcards

Question

How does Copilot access your organisation's data?

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Answer

Through the Microsoft Graph API, using the signed-in user's own access token. Copilot respects all existing M365 permissions — it can only access data the user already has permission to see.

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💡 Show hint

Question

Does Copilot have its own separate data store or admin permissions?

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Answer

No. Copilot does NOT maintain a separate data store, does NOT have elevated permissions, and does NOT bypass any security controls. Its access boundary is identical to the user's.

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Question

If Copilot surfaces sensitive data to a user, what is the root cause?

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Answer

The user already had permission to access that data — Copilot just made it more discoverable. The fix is to correct the overly broad permissions in SharePoint/Exchange/Teams, NOT to configure Copilot differently.

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💡 Show hint

Knowledge Check

Knowledge Check

After Copilot deployment, Northwave's HR team discovers that Copilot is summarising salary data for users outside HR. What is the MOST LIKELY root cause?

ACopilot has a security vulnerability that exposes HR dataBThe salary documents in SharePoint have permissions that are too broad — non-HR users have read accessCMicrosoft Graph provides Copilot with elevated admin access to all SharePoint contentDDLP policies need to be configured to block Copilot from accessing HR data

Check Answer

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Next up: Responsible AI Principles — the ethical framework that governs how Microsoft builds and deploys AI, and what the exam expects you to know.