What is Microsoft Purview Information Protection? Distinguishing sensitivity label usage between E3 and E5
About this article
This article was generated using a generative AI-based automated workflow. Based on official Microsoft information as of September 18, 2026, it outlines Microsoft Purview Information Protection, sensitivity labels, core capabilities in E3, and advanced automation features in E5 and the Purview Suite.Verification status: 📘 Verified with official Microsoft documentation; hardware validation pending.
Information Protection is a framework that classifies documents and emails using sensitivity labels such as Public, Confidential, and Highly Confidential, linking them to visual markings, encryption, and sharing controls as needed.
Labels are available in E3 as well. Automation features must be checked separately.
| Feature | Microsoft 365 E3 | Microsoft 365 E5 / Purview Suite |
|---|---|---|
| Manual labeling by users | Base eligibility | Eligibility |
| Visual marking and protection | Available depending on configuration | Available |
| Advanced auto-labeling | Check additional rights by feature | Includes applicable rights |
| Advanced classification / governance | Limited | Extended |
Rather than asking whether Information Protection is present,manual, recommended, mandatory, and automaticcheck the license based on the implementation level.
flowchart LR D[文書/メール] --> L[秘密度ラベル] L --> V[ヘッダー/透かし] L --> E[暗号化] L --> S[共有制御] A[Auto-labeling] --> L
Try first: Test label without protection
ラベル名: 社内テスト 説明: テスト用。機密情報には使用しない 保護設定: なし 公開先: テストユーザーのみ
Verify that labels appear in supported applications such as Word, Excel, PowerPoint, and Outlook.
Success criteria: Labels appear only for test users, with no unexpected impacts such as documents becoming inaccessible.
Change one location
Next, add only visual markings such as headers or footers. This has less impact than encryption and makes it easier to explain the changes to users.
Start PowerShell with read operations
Security &In environments where you can connect to Compliance PowerShell, you can begin label inventory with read-only operations.
# 接続・権限確認後 Get-Label | Select-Object DisplayName, Name, Priority
Check this: Display name, internal name, and priority.
Success criteria: The list matches the expected labels in the Purview portal.
Change one location：Select-ObjecttoGuidAdd a single read column, such as. Do not perform deletions or bulk modifications.
Example for administrative staff
For departments that draft contracts, rather than applying a company-wide rule from the start that "confidential documents require encryption," the following sequence is safer.
sequenceDiagram participant A as 管理者 participant U as テスト利用者 participant O as Office A->>U: 社内テストラベルを限定公開 U->>O: 手動でラベル適用 O-->>U: ヘッダー等を表示 U-->>A: 分かりやすさ/業務影響を反馈 A->>A: 必要なら保護を段階追加
Three perspectives
General users: It is important that the label name makes it clear what kind of data it represents.
Administrative staff: Align with actual document classifications such as contracts, personal information, and internal materials.
IT/Compliance: Implement label taxonomy, priorities, encryption, auto-labeling, and DLP integration in stages.
Items for administrators to review
Boundary between E3 base labels and E5-series auto-labeling
Clarity of label names and descriptions
Pilot targets
Impact of encryption on external sharing
Supported scope for Office, SharePoint, Teams, etc.
Additional licensing and prerequisites for non-Microsoft 365 data
Official Microsoft information and primary sources
For information protection to take root successfully, rather than applying strong encryption from the beginning, it is easier to establish a classification system, release it to a small group, test with visual markings, and gradually strengthen protection only where necessary.
