Microsoft 365 Copilot Web Search: Delivering Multiple Layers of Protection and Controls

Microsoft

Oct 07, 2025

When you ask Microsoft 365 Copilot or Copilot Chat a question about something that changes fast – earnings updates, a regulatory shift, or a breaking news item – access to current information is critical. That’s why Copilot can ground its answers with current information from the web, closing knowledge gaps that every large language model (LLM) inevitably has based on its training data cutoff. However, more timely and relevant answers only matter if they come with the right enterprise-grade controls.

Traditional web search engines are optimized for broad consumer scenarios. Copilot’s web search is enterprise oriented and layered with controls that consumer search does not provide. The result is a more private and secure approach to web grounding than traditional search.

This post explores web search in Microsoft 365 Copilot – how it works, how it’s protected, and how to roll it out across your organization. We’ll cover the user experience, the four layers of protection (Admin Controls, User Protections, Query Safeguards, and Contractual Commitments), and a practical guide to empower your team to search with confidence.

Why web search matters in Copilot

Consider a simple test: “What’s the name of Seattle’s new professional hockey team?” With web search enabled, Copilot returns the current answer with citations you can click to verify. With web search disabled, Copilot falls back to training data and a historical response that can be outdated or incomplete. That gap is the difference between credible and questionable data as you navigate your flow of work.

The same is true in business contexts. A data analyst asking for “latest quarterly earnings drivers and recent win stories” needs a response grounded in real-time web data, rather than an older snapshot. Web grounding helps Copilot synthesize up to the minute signals with your enterprise context, while keeping guardrails firmly in place.

What actually goes to the web (and what doesn’t)

A Copilot interaction has three parts: your prompt, a web query (if needed), and the response. Let’s imagine you are conducting M+A work in your organization, and you need help with a summary report of financial information about a company of interest.

Prompt: The full written input or instructions the user provides to interact with Copilot. The prompt remains inside the Microsoft 365 service boundary with enterprise data protection.
Web query: If Copilot analyzes the prompt and identifies terms where web information would improve response quality, it generates a short, few word query informed by the user’s prompt (e.g., “Company business strategy”, “Company financials”). That query is stripped of user and tenant identifiers, and does not include any files uploaded in the original prompt. The query is sent securely to the Bing Search Service; relevant web data is returned securely.
Response: Copilot composes an answer grounded on approved enterprise content and the cited web results. In the UI, users see source citations and the exact keywords that were emitted as the web query.

Transparency by design: Users can inspect both the citations and the exact keywords used for web grounding. Additionally, the user's prompts and Copilot's responses are stored within Microsoft 365 and never leave the service boundary for Copilot without customer direction.

The four layers of protection and control

Copilot’s web search is designed with multiple layers of controls that administrators and users can rely on every time a web query is involved. These layers – admin controls, user protections, query safeguards, and contractual commitments – work together to provide secure, transparent, policy-driven handling of web search in Copilot:

Admin Controls

Administrators have precise authority over how and when web search is permitted in Copilot. The Allow Web Search policy lets them scope access by user or group, and by mode (Work vs. Web). Additionally, audit and eDiscovery capabilities provide transparency . Every emitted web query is logged and can be linked to the originating prompt and response. These logs are accessible through Microsoft Purview eDiscovery and Data Security Posture Management activity explorer, enabling targeted audits and investigations when needed.

User Protections

Users also have control. In the Work tab, they can toggle web grounding on or off, choosing to stay “work only” or bring in the web when needed. This flexibility empowers users to tailor their experience based on context.

Copilot also enforces responsible AI (RAI) protections, which automatically reject certain terms, phrases, or patterns that may pose risks. Transparency is built into the experience, so users see citations to sources and the exact keywords Copilot securely sends out when performing web grounding. This helps users understand how their queries are processed and where information comes from.

Query Protections

Copilot sends only the essential keywords needed to retrieve current information. It avoids transmitting the full prompt unless the prompt itself is very short. Before transmission, user and tenant identifiers are removed, and all queries are sent securely to Bing. The results are returned securely, and both the prompt and response remain within the Microsoft 365 service boundary.

Contractual Commitments

Microsoft’s product terms codify strict commitments around query data. Microsoft has no rights in query data beyond what’s needed to provide the service. Query data is not used to improve Bing, train generative AI foundation models, or create advertising profiles. It is not shared with advertisers or beyond Microsoft. Instead, it is treated as Customer Confidential Information, reinforcing Microsoft’s commitment to privacy and trust.

Key Considerations for Rolling Out Copilot Web Search

Whether you’re piloting with a single department or ready to scale across your organization, this step-by-step approach balances value with control:

Start with a policy stance that maximizes value

Default to keeping web search enabled while scoping access via security groups. Pilot with champions in a few departments, such as Finance, Sales, and Legal to capture diverse scenarios and early feedback.

Protect sensitive files with Data Loss Prevention (DLP) for Copilot

Deploy or refine sensitivity labels and enforce them with DLP for Copilot in chat and the Office apps. This keeps highly sensitive files from being processed by Copilot and being used to inform emitted web queries. Validate with real documents before production rollout.

Turn on logging and define an audit rhythm

Coordinate with your security and compliance teams to:

Confirm query logging is visible in Purview eDiscovery alongside prompts and responses.
Spot‑check a sample of interactions that include web grounding to monitor for policy alignment and acceptable use.
Establish an escalation path for out of policy findings (e.g., retraining, policy adjustment).

Train users on transparency and control

Create a short enablement module that shows:

How to recognize citations and view the exact keywords used for web grounding.
How to toggle web search in the Work tab when handling sensitive tasks.
What it means when Copilot refuses to process a labeled document, and why that’s a feature, not a bug.

Document permitted and restricted scenarios

Publish a use case matrix (allowed / needs care / not allowed). Examples include:

Allowed: Market trend summaries with citations; public company comparisons; public standards lookups.
Needs care: M&A diligence prompts – ensure prompt content doesn’t disclose non‑public details
Not allowed: Drafting with content derived from Confidential or Highly Confidential labels if DLP policy prohibits processing.

Pro tip: Validate and tune your label taxonomy (e.g., General, Confidential, Highly Confidential) before broad enablement so DLP for Copilot enforces your intended policies from day one.

You’re in control from end to end

Copilot’s web grounding delivers more relevant, reliable answers while keeping your organization firmly in control through policy, transparency, safeguards, and contractual commitments. Enable it where it adds the most value, pair it with DLP for Copilot, and use logging and eDiscovery to verify it’s being used the way you intend.

That’s how you get better answers with stronger guardrails, and the confidence to scale.