Clarification on Microsoft Purview Sensitivity Labels – Preventing Label Downgrade and File Forwarding in SharePoint/OneDrive

Question

Hello Microsoft Support Team,

Our organization is currently using Microsoft 365, and I would like to better understand Microsoft Purview Information Protection capabilities for enhanced data governance. I would like clarification on the following scenarios regarding Sensitivity Labels applied to documents stored in SharePoint Online and OneDrive:

1️⃣ Label Downgrade Control

Q1: If a document is labeled as “Highly Confidential” by a data owner:

• Can other users (non-owners) downgrade the label to a lower classification?
• Under what conditions is label downgrade technically restricted?

Q2: Is label downgrade restricted based on:

• Ownership?
• Usage rights (Owner / Co-Owner / Co-Author)?
• Policy configuration?
• Licensing tier (E3 vs E5)?

Q3: Is there a supported method to:

• Completely prevent label downgrade?
• Require administrative approval before a label can be downgraded

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2️⃣ Forwarding / Sharing Control For documents stored in SharePoint or OneDrive:

Q4: If a Sensitivity Label enforces encryption and restricted usage rights:

• Can users still share the file externally?
• Can they download and re-upload the file with modified classification?
• Can co-authors change classification if they are not the original owner?

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3️⃣ User-Defined Classification Risk If employees are allowed to manually choose classification labels:

Q5: What governance mechanisms does Microsoft recommend to:

• Prevent intentional mislabeling?
• Prevent users from lowering classification before sharing?
• Enforce automatic labeling instead of manual selection?

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4️⃣ Best Practice Design

Q6: Could you provide guidance or official documentation on:

• Recommended architecture for preventing classification downgrade
• Recommended combination of:

1. Sensitivity Labels
2. Auto-labeling
3. DLP policies
4. Conditional Access
5. Endpoint DLP
6. Licensing requirements to enforce strict downgrade prevention

Thank you.

Answer 1

Hey @Sylvia Guo , thanks for all the great questions. Based on the Microsoft Purview docs you shared, here’s what we can confirm today—and where we need a bit more detail from you to dig deeper.

1️⃣ Label Downgrade Control (Q1–Q3)

We didn’t find explicit details in the provided documentation on locking down label downgrade or requiring admin approval before downgrade. To help us nail down an answer, could you clarify:

• Are you using the Microsoft Purview unified labeling client (in Office apps) or just IRM library‐level settings in SharePoint/OneDrive?

• Which sensitivity label settings do you have configured (e.g. “Users can remove this label” checked/unchecked)?

• What Office/Microsoft 365 license SKUs are assigned to users (E3 vs. E5 vs. AIP Plan 1/2)?

• Do you have any custom retention or DLP policies that might override or interact with label settings?

2️⃣ Forwarding/Sharing Control (Q4)

From “Configure SharePoint with a sensitivity label to extend permissions to downloaded documents” and “Enable sensitivity labels for files in SharePoint and OneDrive”:

• If you apply a sensitivity label with encryption and restricted usage rights to a document library, any file downloaded inherits those site permissions. Only users who still have access in SharePoint/OneDrive can open it—external recipients won’t be able to open/download it if they aren’t in the original access list.

• The label and encryption persist on the file, so even if someone downloads then re-uploads it elsewhere, the original label/encryption stays in place and unauthorized users can’t open it.

• Co-authors in Office for the web can’t remove or change that label if the encryption setting is enforced—only users with the right SharePoint permissions and label rights can reclassify.

3️⃣ User-Defined Classification Risk (Q5) & Best Practices (Q6)

The docs you shared focus on classification scanning and label deployment—not governance controls around manual mislabeling or approval workflows. To advise on preventing intentional mislabeling and enforcing auto-labeling, could you tell us:

• Do you currently have auto-labeling/scanning rules in Purview Data Map or Office 365 DLP policies?

• Are you looking to block users from selecting lower labels altogether, or just require a justification/approval step?

• Have you explored combining Conditional Access or Endpoint DLP to block copy/paste or block unapproved apps that could strip protection?

• What’s your target licensing mix (e.g. EMS E5, Microsoft 365 E5, AIP Plan 2)?

Once we have that info, we can point you at the exact label policy settings, DLP rule examples, auto-labeling steps, Conditional Access policies, and Endpoint DLP configurations that will lock down downgrade and mislabeling.

References

1. Configure SharePoint with a sensitivity label to extend permissions to downloaded documents https://learn.microsoft.com/purview/sensitivity-labels-sharepoint-extend-permissions
2. Enable sensitivity labels for files in SharePoint and OneDrive https://learn.microsoft.com/purview/sensitivity-labels-sharepoint-onedrive-files
3. Microsoft Purview service description (licensing matrix for sensitivity labeling) https://learn.microsoft.com/office365/servicedescriptions/microsoft-365-service-descriptions/microsoft-365-tenantlevel-services-licensing-guidance/microsoft-purview-service-description