Integrations verified 2026-10-15

E5 Add-ons: Tools That Plug Into Microsoft 365

Startups with a native Microsoft 365 integration, what gap each targets vs E5, and where they overlap with what E5 already includes.

Browse tools

Not an endorsement. This is a neutral directory, listed alphabetically within each category. It does not rank or recommend any product and implies no partnership, affiliation or sponsorship. Listing a tool does not imply that any organization uses it. There are no affiliate links.

Tools

Backup

Keepit

Gap vs E5: Third-party backup and recovery of Microsoft 365, Entra ID, Dynamics 365 and Power Platform data in a separate, vendor-independent cloud.
How it integrates: Listed on Microsoft Marketplace as backup and recovery for Microsoft applications.; Proof: Microsoft Marketplace listing (checked 2026-10-15)
Overlap with E5: E5 does not include a separate third-party backup copy; Microsoft 365 retention and eDiscovery are compliance features, not independent backup. Overlap is limited.
Founded: 2007 · Vendor press release ("Founded in 2007") (checked 2026-10-15)
Funding stage: Venture/growth-backed: $50M round (Dec 16, 2024; the release does not name a series) · Vendor press release (checked 2026-10-15)

Data security / DSPM

Cyera

Gap vs E5: Vendor describes AI-based discovery and classification of sensitive data across Microsoft 365 stores, including data Purview has not labeled, plus remediation of public and organization-wide sharing.
How it integrates: Connects Microsoft 365 data stores (OneDrive, SharePoint, Teams, Exchange Online) and works with Microsoft Purview sensitivity labels, per the vendor.; Proof: Vendor page: Cyera + Microsoft Purview (checked 2026-10-15) · Vendor release: remediation for Microsoft 365 (checked 2026-10-15)
Overlap with E5: E5 includes Purview Information Protection Plan 2 (auto-labeling) and Purview DLP. The vendor says it "doesn't replace Purview"; overlap is in classification and labeling.
Founded: not public
Funding stage: Series E (per vendor press release) · Vendor press release (checked 2026-10-15)

Data security / DSPM

Teleskope

Gap vs E5: Vendor describes automated discovery, classification and remediation of sensitive data, including SharePoint and OneDrive access-risk review.
How it integrates: Entra app registration with Microsoft Graph application permissions (Files.Read.All, Sites.Read.All and others); optional Purview sensitivity-label actions.; Proof: Vendor setup doc: SharePoint & OneDrive (checked 2026-10-15)
Overlap with E5: E5 includes Purview Information Protection Plan 2 and DLP for SharePoint and OneDrive. Overlap is in classification; the vendor can apply Purview labels rather than replacing them.
Founded: not public
Funding stage: Series A ($25M, led by M13) · Press release (Business Wire) (checked 2026-10-15)

Email security

Abnormal Security (Abnormal AI)

Gap vs E5: Vendor describes behavioral-AI detection of business email compromise, credential phishing and other socially engineered email attacks, layered on top of Microsoft 365 email protection.
How it integrates: API connection to Microsoft 365 (no MX change, per the listing); listed on Microsoft Marketplace; Microsoft Sentinel data connector.; Proof: Microsoft Marketplace listing (checked 2026-10-15) · Microsoft Sentinel connector reference (Abnormal Security) (checked 2026-10-15)
Overlap with E5: E5 includes Defender for Office 365 Plan 2 (anti-phishing, Safe Links, Safe Attachments, automated investigation). Overlap is partial; the vendor positions itself as additive to Microsoft protection.
Founded: not public
Funding stage: Series D (announced Aug 6, 2024) · Vendor press release (checked 2026-10-15)

Email security

Sublime Security

Gap vs E5: Vendor describes an email security platform with customizable detections, threat hunting and the option to self-host.
How it integrates: Microsoft Graph API application permissions (Mail.ReadWrite and others) granted to an app registration in the Microsoft 365 tenant.; Proof: Vendor setup doc: Microsoft 365 (checked 2026-10-15)
Overlap with E5: E5 includes Defender for Office 365 Plan 2. Overlap is substantial for phishing and malware protection; the difference the vendor describes is detection customization.
Founded: not public
Funding stage: Series B (announced Dec 12, 2024) · Press release (checked 2026-10-15)

Identity

Silverfort

Gap vs E5: Vendor describes extending MFA and access policies to resources that do not support modern authentication natively, such as on-premises and legacy systems.
How it integrates: Silverfort Microsoft Entra Adapter enterprise app; protected assets appear in Entra ID for Conditional Access and SSO (Microsoft Learn tutorial).; Proof: Microsoft Learn: Entra ID and Silverfort (checked 2026-10-15)
Overlap with E5: E5 includes Entra ID P2 (Conditional Access, risk-based policies) and Defender for Identity. Overlap is in policy enforcement for cloud apps; the gap is legacy and on-premises resources.
Founded: not public
Funding stage: Series D (announced Jan 23, 2024) · Vendor press release (checked 2026-10-15)

SaaS security

AppOmni

Gap vs E5: Vendor describes SaaS security posture management: continuous monitoring of Microsoft 365 configuration, permissions and drift.
How it integrates: Vendor solution overview describes Microsoft 365 coverage and integration with Microsoft Entra ID.; Proof: Vendor solution overview (PDF) (checked 2026-10-15)
Overlap with E5: E5 includes Defender for Cloud Apps (SaaS posture and app governance) and Secure Score. Overlap is substantial for Microsoft 365 posture; the vendor also covers non-Microsoft SaaS.
Founded: 2018 · Vendor about page (checked 2026-10-15)
Funding stage: Series C (June 2022, per vendor release) · Vendor press release (checked 2026-10-15)

SaaS security

Obsidian Security

Gap vs E5: Vendor describes monitoring of Entra ID integrations, access and compliance, and SaaS identity threat detection.
How it integrates: Vendor integration page for Microsoft Graph / Entra ID.; Proof: Vendor integration page: Microsoft Graph - Entra ID (checked 2026-10-15)
Overlap with E5: E5 includes Entra ID P2 (Identity Protection), Defender for Cloud Apps and Defender for Identity. Overlap is substantial within Microsoft 365; the vendor also covers other SaaS.
Founded: 2017 · Vendor press release ("founded in 2017") (checked 2026-10-15)
Funding stage: Series C · Vendor press release (checked 2026-10-15)

Method

Scope: Venture-backed startups with a native Microsoft 365 integration (Graph API, Sentinel connector, Entra ID, Purview, Defender XDR or Microsoft Marketplace), verified live on the date checked.
Categories: Backup (1), Data security / DSPM (2), Email security (2), Identity (1), SaaS security (2).
Founded year and funding stage come from public pages linked on each card. Where no live public source confirmed them, they show "not public".
Fetched politely: robots.txt checked, one request at a time with 6-second pauses.

Not included

Afi (Afi.ai): The Microsoft Marketplace listing verified the integration, but no live public source confirmed venture backing or a funding stage, so it doesn't meet the startup scope.
Large public or mega vendors (for example Proofpoint, Mimecast, Palo Alto Networks, CrowdStrike, Microsoft, Okta, CyberArk, Zscaler, Varonis): Excluded by scope: startups only.
Vendors acquired by large companies (for example Tessian, Avanan, Adaptive Shield): Excluded by scope: no longer independent startups.

Corrections: [email protected].