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Announcing Public Preview of DLP for M365 Copilot in Word, Excel, and PowerPoint

Camille_Birch's avatar
Camille_Birch
Icon for Microsoft rankMicrosoft
May 01, 2025

Today, we are excited to announce the public preview of Data Loss Prevention (DLP) for M365 Copilot in Word, Excel, and PowerPoint. This development extends the capabilities you rely on for safeguarding data in M365 Copilot Chat, bringing DLP protections to everyday Copilot scenarios within these core productivity apps. 

Building on Our Foundation 

Data oversharing and leakage is a top concern for organizations using generative AI technology, and securing AI-based workflows can feel overwhelming. We’ve been laying a strong foundation with Microsoft Purview Data Loss Prevention—especially with DLP for M365 Copilot—and are excited to expand its reach to further reduce the risk of AI-related oversharing at scale. 

In the original public preview release, we enabled admins to configure DLP rules that block Copilot from processing or summarizing sensitive documents in M365 Copilot Chat. However, these controls didn’t extend to the powerful in-app Copilot experiences, such as rewriting text in Word, summarizing presentations in PowerPoint, or generating helpful formulas in Excel. That changes now with this public preview. 

The Next Phase of DLP for M365 Copilot 

Similar to our original approach for M365 Copilot Chat, we are bringing consistent, flexible protection to M365 Copilot for Word, Excel, and PowerPoint. Here’s how it works in this preview: 

Current file DLP checks: Copilot now respects sensitivity labels on an opened document or workbook. If a document has a sensitivity label and a DLP rule that excludes its content from Copilot processing, Copilot actions like summarizing or auto-generating content directly in the canvas are blocked. Chatting with Copilot is also unavailable. 

File reference DLP checks: When a user tries to reference other files in a prompt – like pulling data or slides from other labeled documents – Copilot checks DLP policies before retrieving the content. If there is a DLP policy configured to block Copilot processing of files with that file’s sensitivity label, Copilot will show an apology message rather than summarizing that content – so no accidental oversharing occurs. 

You can learn more about DLP for M365 Copilot here: Learn about the Microsoft 365 Copilot policy location (preview)

Getting Started 

Enabling DLP for M365 Copilot in Word, Excel, and PowerPoint follows a setup similar to configuring DLP policies for other workloads. From the Purview compliance portal, you can configure the DLP policy for a specific sensitivity label at a file, group, site, and/or user level. If you have already enabled a DLP for M365 Copilot policy with the ongoing DLP for M65 Copilot Chat preview, no further action is needed – the policy will automatically begin to apply in Word, Excel, and PowerPoint Copilot experiences. 

In this preview, our focus is on ensuring reliability, performance, and seamless integration with the Office apps you use every day. We’ll continue to refine the user experience as we move toward general availability, including improvements to error messages and user guidance for each scenario. 

Join the Preview 

This public preview reflects our ongoing commitment to deliver robust data protection for AI-powered workflows. By extending the same DLP principles you trust to Word, Excel, and PowerPoint, we’re empowering you to embrace AI confidently without sacrificing control over your organization’s most valuable information. 

We invite you to start testing these capabilities in your environment. Your feedback is invaluable to us – we encourage all customers to share their experiences and insights, helping shape the next evolution of DLP for M365 Copilot in Office. 

Updated Apr 30, 2025
Version 1.0

4 Comments

  • Navan05's avatar
    Navan05
    Copper Contributor

    Hey Camille, is there something we would need to do specifically to enable this? Would I need to create a new policy or would my existing policy work on these directly? 

    • Camille_Birch's avatar
      Camille_Birch
      Icon for Microsoft rankMicrosoft

      If you've already enabled a DLP for M365 Copilot policy as a part of the DLP for M65 Copilot Chat preview, this policy will automatically begin to apply in Word, Excel, and PowerPoint Copilot experiences -- no new policy creation is needed.

  • Dean_Gross's avatar
    Dean_Gross
    Silver Contributor

    Camille_Birchthis looks very promising, what happens when files don’t have labels? Does it look for underlying sensitive information types?

    • Camille_Birch's avatar
      Camille_Birch
      Icon for Microsoft rankMicrosoft

      Hi Dean_Gross, this feature currently only supports sensitivity labels as a DLP condition. Support for other DLP conditions are under consideration by the product group.

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