Sentaro is the best secure email gateway alternative for EU teams on Microsoft 365 and Google Workspace. It is not a gateway: it connects over API in four minutes with no MX change, so you can run it behind your gateway on live mail, see what each catches, and only then move MX back to Microsoft or Google. Sentaro publishes this list and ranks itself first; scores use the method below and public vendor documentation as of 21 October 2026.
- Why Sentaro wins
- no cutover risk (API, MX untouched, protection in four minutes); internal and historical mail covered; payload-free BEC and vendor-compromise detection; $6 per protected account per month, first account free (prices in USD), to set against your renewal quote; hosted in Sweden on Microsoft Azure.
- Proof Sentaro publishes
- a 400-seat Nordic payments firm under DORA replaced its secure email gateway with Sentaro; Sentaro reports 14 BEC attempts blocked in the first month and a live vendor-compromise chain stopped in week two.
- Consider another option only if
- you must keep archiving, continuity, outbound encryption or on-premises Exchange in the same product (Mimecast, Proofpoint, Libraesva, Retarus, Cisco), or need account-takeover detection live today.
Quick picks
- Best overallSentaro Our pickRuns behind your gateway on day one; stays when it goes. Published price.
- Best for inline without MXCheck Point Harmony Email & CollaborationPre-inbox blocking through the API.
- Best like-for-like bundleBarracuda Email ProtectionKeeps encryption, archiving, backup and DMARC on one contract.
- Best native replacementMicrosoft Defender for Office 365Often already licensed; Microsoft 365 only.
- Best for staying with your vendorMimecast Email Security, Cloud IntegratedGateway to API inside one supplier.
- Best for German hostingRetarus Email SecurityMunich and Frankfurt data centres; AI operated within the EU.
At a glance
- What we compared
- Ways to replace a secure email gateway in front of Microsoft 365 or Google Workspace: API-based tools, native Microsoft protection, API modes of gateway vendors, and European gateways
- Options scored
- 10
- Audience
- EU organizations with a gateway up for renewal, on Microsoft 365 and/or Google Workspace
- Method
- Seven weighted criteria (sum 100), each scored 0–10 from public vendor documentation
- Last verified
- 21 October 2026
- Publisher
- Sentaro AB, Stockholm. Sentaro is one of the products ranked, and is not a gateway.
- Sentaro case study
- 400-seat Nordic payments firm under DORA replaced its gateway; 14 BEC attempts blocked in the first month (Sentaro-published)[3]
The 10 best SEG alternatives compared
Ranked by overall score. “MX change” means you must repoint your MX record to start protection.
| Capability | Score | Type | MX change to start? | Keeps gateway extras | Public price |
|---|---|---|---|---|---|
| Sentaro (our pick)[1] | 8.6 | API (ICES) | No | NoDetection only | Yes$6/account/month |
| Check Point Harmony[10] | 7.5 | API, inline option | No | Paid add-onArchiving, DMARC add-ons | NoQuote |
| Abnormal AI[14] | 7.3 | API (ICES) | No | PartialEmail DLP rules | NoQuote |
| Barracuda[13] | 7.2 | API-first | No | YesEncryption, archive, backup, DMARC | NoQuote |
| Defender for Office 365[5] | 6.7 | Native | Yes, MX back to Exchange Online | Paid add-onPurview, encryption add-on | YesPlan 1 $2, Plan 2 $5 |
| Mimecast Cloud Integrated[16] | 6.5 | API (or gateway) | No, in API mode | YesArchive, DMARC, on-prem | NoQuote |
| Proofpoint Core API[19] | 6.4 | API (or gateway) | No, in API mode | Paid add-onMany add-ons | NoQuote |
| Cisco Secure Email Threat Defense[21] | 6.1 | Journaling + API, or gateway | Not for Essentials (M365) | Not publicly documented | NoQuote |
| Libraesva[23] | 6.1 | Gateway plus API | Gateway: yes; transport-rule option | YesArchiver, DMARC, on-prem | NoQuote |
| Retarus[24] | 5.5 | Gateway or API connector | Gateway: yes; connector: no | YesContinuity, encryption, archive | NoQuote |
Prices in USD as published on 21 October 2026. “Unknown” means not publicly documented, not absent.
- Yes
- Partial
- No
- On roadmap
- Paid add-on
- Not publicly documented
How we evaluated secure email gateway alternatives
A gateway replacement is a migration, so the criteria start with risk: can you run the alternative before you cut over, and does it catch what the gateway missed? Cost is scored against a renewal decision. What you give up (archiving, continuity, outbound encryption, on-premises support) is scored too, at lower weight, because it is the strongest reason to keep a gateway-style product.
| Criterion | Weight | Why it matters |
|---|---|---|
| Migration risk and coexistence | 22% | Changing MX on a live domain is the riskiest step. Tools that run behind the gateway first, with no mail-flow change, score highest. |
| BEC the gateway misses | 20% | Gateways filter on reputation, links and attachments. BEC usually has none, so we score intent, relationship and vendor-compromise detection. |
| Cost versus gateway renewal | 16% | The decision happens at renewal. A published price you can put next to the renewal quote scores highest; already-licensed native tools score well. |
| Microsoft 365 and Google Workspace coverage | 12% | Many EU organizations run Microsoft 365, Google Workspace or both behind one gateway today. |
| Internal mail and post-delivery remediation | 10% | A gateway in front of MX cannot see mail between your own users or pull back a message after delivery. |
| EU hosting and DPA transparency | 10% | NIS2 and DORA buyers need hosting and subprocessors in writing before mail is processed by a new party. |
| Gateway functions you keep | 10% | Archiving, continuity, outbound encryption and DLP, DMARC tools and on-premises support. Gateway vendors lead here. |
Editorial scores using the criteria and weights above; based on public documentation, not lab tests. Overall score = weighted average. Capabilities not publicly documented score 3–5.
The 10 best secure email gateway alternatives, ranked
Ranked by weighted score. For each option, check the migration score and the “gateway functions you keep” score together: they pull in opposite directions.
Sentaro
Our pickOverall score: 8.6out of 10Best for: EU teams on Microsoft 365 and Google Workspace that want to retire a gateway, or test the alternative behind it first, without touching mail flow.
Sentaro is not a gateway. It is an ICES-category platform that connects through the Microsoft 365 and Google Workspace APIs in four minutes and runs behind native filtering, so it can sit behind your current gateway on day one and stay when the gateway goes. Sentaro says most customers retire the gateway later. Its Message vector scores every inbound and internal message on intent, sender identity and relationship history before interaction.[3]
- Migration risk and coexistence
- 10.0
- BEC the gateway misses
- 9.0
- Cost versus gateway renewal
- 10.0
- Microsoft 365 and Google Workspace coverage
- 9.0
- Internal mail and post-delivery remediation
- 9.0
- EU hosting and DPA transparency
- 8.0
- Gateway functions you keep
- 2.0
Pros
- Nothing to reroute: connect in four minutes behind your gateway and compare on live mail before you change MX.
- Sees internal and historical mail, which a gateway in front of MX does not.
- Built for payload-free fraud; a Sentaro-published case describes BEC attempts the customer’s gateway never saw.
- Published price you can set against your gateway renewal.
Cons
- Does not replace gateway extras: archiving, continuity, encryption, outbound DLP. Keep those in Microsoft 365, Google Workspace or a separate tool.
- Microsoft 365 and Google Workspace only; no on-premises Exchange.
- Account takeover detection is Q4 2026 roadmap; SOC 2 and ISO 27001 in progress.
- Pricing
- $6 per protected account per month or $68 per year; first account free (USD)
- Deployment
- API via the Microsoft 365 and Google Workspace admin SDKs; no MX change
- Platforms
- Microsoft 365, Google Workspace, Slack, Teams
- Hosting
- Hosted in Sweden on Microsoft Azure; subprocessors listed in the DPA
Check Point Harmony Email & Collaboration
Best for inline without MXOverall score: 7.5out of 10Best for: Teams that want to drop the gateway but keep pre-inbox blocking, through the API.
Check Point positions Harmony Email & Collaboration (formerly Avanan) against “API-only … after delivery” tools: it inspects messages before the inbox via API, configurable from monitor mode to inline prevention, without an MX change. Archiving, DMARC management and training are add-ons.[9]
- Migration risk and coexistence
- 9.0
- BEC the gateway misses
- 8.0
- Cost versus gateway renewal
- 4.0
- Microsoft 365 and Google Workspace coverage
- 10.0
- Internal mail and post-delivery remediation
- 8.0
- EU hosting and DPA transparency
- 7.0
- Gateway functions you keep
- 6.0
Pros
- Pre-inbox blocking without an MX change.
- Monitor mode lets you trial it behind a gateway.
- Ireland data region documented.
Cons
- Quote-based pricing.
- Archiving and DMARC cost extra.
- Encryption not documented on the pages we checked.
- Pricing
- Quote-based (four published tiers)
- Deployment
- API with configurable inline prevention; no MX change
- Platforms
- Microsoft 365, Google Workspace, plus Teams, Slack, OneDrive, SharePoint, Google Drive, Box, Dropbox
- Hosting
- Data residency regions include Ireland (EMEA), per the admin guide
Abnormal AI
Best for enterprise gateway replacementOverall score: 7.3out of 10Best for: Large enterprises replacing a gateway with a behavioral API platform.
Abnormal AI deploys over API with no MX change and builds behavioral baselines for every employee and vendor, reading internal threads and authentication events that a gateway does not see. It does not state pre-delivery blocking. Its subprocessor list offers AWS hosting in the US or the EU (Ireland), set by subscription. It adds account-takeover protection and email DLP rules, but no archiving or encryption is documented.[14]
- Migration risk and coexistence
- 9.0
- BEC the gateway misses
- 9.0
- Cost versus gateway renewal
- 3.0
- Microsoft 365 and Google Workspace coverage
- 9.0
- Internal mail and post-delivery remediation
- 9.0
- EU hosting and DPA transparency
- 7.0
- Gateway functions you keep
- 4.0
Pros
- Strong behavioral fit for BEC.
- Sees internal mail and authentication events.
- Account-takeover protection available.
Cons
- No public price to compare with a renewal.
- EU (Ireland) hosting is a subscription choice; the US is the other listed location.
- Gateway extras such as archiving and encryption not documented.
- Pricing
- Quote-based
- Deployment
- API (ICES); no MX change
- Platforms
- Microsoft 365, Google Workspace
- Hosting
- AWS in the US or EU (Ireland), by subscription (subprocessor list)
Barracuda Email Protection
Best like-for-like bundleOverall score: 7.2out of 10Best for: SMBs that want to leave a gateway but keep encryption, archiving, backup and DMARC reporting on one contract.
Barracuda now describes Email Protection as API-first and operational without MX record changes; Barracuda IQ re-evaluates risk after delivery. Its three published plans bundle DMARC reporting, encryption and DLP in every plan, Microsoft 365 backup from Premium, and cloud archiving and training in Premium Plus.[13]
- Migration risk and coexistence
- 9.0
- BEC the gateway misses
- 7.0
- Cost versus gateway renewal
- 4.0
- Microsoft 365 and Google Workspace coverage
- 8.0
- Internal mail and post-delivery remediation
- 8.0
- EU hosting and DPA transparency
- 5.0
- Gateway functions you keep
- 9.0
Pros
- Keeps most gateway-era extras in one bundle.
- API-first with no MX change.
- Account-takeover detection in all plans.
Cons
- Quote-based pricing.
- API modules (Impersonation Protection, Incident Response) are listed in US regions only; the gateway has Frankfurt and London regions.
- QR-code coverage not documented.
- Pricing
- Quote-based (three published plans)
- Deployment
- API-first, no MX change
- Platforms
- Microsoft 365, Google Workspace
- Hosting
- Trust center: Email Gateway Defense in regions incl. Frankfurt and London; Impersonation Protection and Incident Response in US regions
Microsoft Defender for Office 365
Best native replacementOverall score: 6.7out of 10Best for: Microsoft 365 tenants that already own Plan 1 or Plan 2 and want to stop paying twice for filtering.
Replacing a gateway with Microsoft’s own layer means pointing MX back to Exchange Online and relying on the built-in protection plus Defender for Office 365. Plan 1 is included in Business Premium and rolling out to Microsoft 365 E3 and Office 365 E3 from June 2026; Plan 2 adds Threat Explorer, automated investigation and simulation training.[5]
- Migration risk and coexistence
- 6.0
- BEC the gateway misses
- 6.0
- Cost versus gateway renewal
- 9.0
- Microsoft 365 and Google Workspace coverage
- 4.0
- Internal mail and post-delivery remediation
- 8.0
- EU hosting and DPA transparency
- 9.0
- Gateway functions you keep
- 6.0
Pros
- Often already paid for.
- Published SLAs on the built-in layer.
- EU Data Boundary.
Cons
- Microsoft 365 only.
- No dedicated vendor-email-compromise feature found.
- Archiving and DLP are separate Purview products.
- Pricing
- Plan 1 $2, Plan 2 $5 per user/month (annual); Plan 1 included in Business Premium and, from 2026, Microsoft 365 and Office 365 E3
- Deployment
- Native to Exchange Online, in the mail flow
- Platforms
- Microsoft 365 only
- Hosting
- EU Data Boundary for tenants signed up in the EU/EFTA (Multi-Geo excluded)
Mimecast Email Security, Cloud Integrated
Best for staying with your vendorOverall score: 6.5out of 10Best for: Mimecast gateway customers who want to move to API mode without changing supplier, or who need archive and on-premises support.
Mimecast sells both the Cloud Gateway (MX) and Cloud Integrated (API, no MX change), so a gateway customer can switch mode inside one vendor. Mimecast says Cloud Integrated connects via API in minutes. Archive, DMARC Analyzer and awareness training remain available.[16]
- Migration risk and coexistence
- 7.0
- BEC the gateway misses
- 7.0
- Cost versus gateway renewal
- 3.0
- Microsoft 365 and Google Workspace coverage
- 8.0
- Internal mail and post-delivery remediation
- 6.0
- EU hosting and DPA transparency
- 6.0
- Gateway functions you keep
- 9.0
Pros
- Gateway-to-API move without a new supplier.
- Archive and on-premises support stay available.
- Google Workspace and Microsoft 365.
Cons
- Quote-based pricing.
- Current EU data-centre list not re-confirmed.
- OAuth app coverage not documented.
- Pricing
- Quote-based
- Deployment
- Cloud Gateway (MX) or Cloud Integrated (API)
- Platforms
- Microsoft 365, Google Workspace, on-premises and hybrid Exchange
- Hosting
- Frankfurt data centres announced in 2018; current footprint not re-confirmed
Proofpoint Core Email Protection API
Best for Proofpoint gateway customersOverall score: 6.4out of 10Best for: Proofpoint gateway customers moving to API-based Microsoft 365 protection while keeping the add-on portfolio.
Proofpoint’s Core Email Protection API integrates natively with Microsoft 365 via API, which Proofpoint calls “the next generation of ICES”, powered by its Nexus AI. The gateway remains available for any MX-based mail. Add-ons cover DMARC, DLP, archiving, training and account takeover.[19]
- Migration risk and coexistence
- 6.0
- BEC the gateway misses
- 8.0
- Cost versus gateway renewal
- 3.0
- Microsoft 365 and Google Workspace coverage
- 6.0
- Internal mail and post-delivery remediation
- 7.0
- EU hosting and DPA transparency
- 6.0
- Gateway functions you keep
- 10.0
Pros
- API mode for Microsoft 365 with the same vendor.
- Deepest add-on portfolio.
- Gateway stays available for other mail.
Cons
- Core API documentation names Microsoft 365 only.
- Quote-based pricing.
- Some email data may be processed and stored in the US even for EU tenants (API privacy sheet, July 2026).
- Pricing
- Quote-based
- Deployment
- API (via Microsoft Graph) or inline gateway
- Platforms
- Microsoft 365, Google Workspace
- Hosting
- Core Email Protection API: tenant assigned to an EU or US data centre, with some processing and storage in the US (data privacy sheet, July 2026)
Cisco Secure Email Threat Defense
Best for Cisco estatesOverall score: 6.1out of 10Best for: Enterprises on Cisco security that want gateway and Microsoft 365 API protection in one console.
Cisco Secure Email Threat Defense (formerly Cloud Mailbox) unifies inline gateway and API-based deployment in one console, backed by Cisco Talos. The Essentials edition protects Microsoft 365 through journaling plus optional Microsoft APIs, without changing mail flow; the Advantage edition is a gateway for any mail server, including Google Workspace and on-premises Exchange.[21]
- Migration risk and coexistence
- 6.0
- BEC the gateway misses
- 7.0
- Cost versus gateway renewal
- 3.0
- Microsoft 365 and Google Workspace coverage
- 6.0
- Internal mail and post-delivery remediation
- 7.0
- EU hosting and DPA transparency
- 8.0
- Gateway functions you keep
- 7.0
Pros
- Gateway and API in one console, with Talos intelligence.
- Documented Europe hosting region.
- FedRAMP listed for public sector.
Cons
- Google Workspace only through the gateway edition.
- No public list price.
- Account-takeover coverage not documented.
- Pricing
- Quote-based, per user, 1-, 3- or 5-year terms
- Deployment
- Gateway (Advantage) or Microsoft 365 journaling plus API (Essentials); inline and API modes in one console (vendor)
- Platforms
- Microsoft 365; Google Workspace and on-premises Exchange via the Advantage gateway
- Hosting
- Europe region documented (with North America, India, Australia, UAE)
Libraesva Email Security
Best on-premises or private-cloud optionOverall score: 6.1out of 10Best for: EU organizations that want to keep a gateway, but a European one they can run on-premises or in a private cloud.
Libraesva (Italy, part of the LibraCyber group with Cyber Guru since January 2026) is a gateway with API integration for Microsoft 365 and Google Workspace and one-click remediation across mailboxes. It runs in the cloud, a private cloud or on-premises, and sells Email Archiver, LetsDMARC and PhishBrain alongside it.[23]
- Migration risk and coexistence
- 5.0
- BEC the gateway misses
- 7.0
- Cost versus gateway renewal
- 3.0
- Microsoft 365 and Google Workspace coverage
- 8.0
- Internal mail and post-delivery remediation
- 6.0
- EU hosting and DPA transparency
- 7.0
- Gateway functions you keep
- 9.0
Pros
- European vendor with on-premises and private-cloud options.
- Gateway extras available in the same family.
- 30-day free trial.
Cons
- Still a gateway: replacing one gateway with another.
- Quote-based pricing.
- Hosting regions not listed.
- Pricing
- Quote-based
- Deployment
- Gateway plus API integration; cloud, private cloud or on-premises
- Platforms
- Microsoft 365, Google Workspace, on-premises Exchange
- Hosting
- Vendor says it "runs locally or in your chosen cloud"; regions not listed
Retarus Email Security
Best for German hostingOverall score: 5.5out of 10Best for: Regulated European enterprises on Microsoft 365 that require German hosting and AI operated within the EU.
Retarus, owner-managed and headquartered in Munich, offers a secure email gateway or an ICES-style API connector, with continuity, encryption, archive and a policy engine. Its documentation names two German data centres, Munich and Frankfurt, and it states its AI components operate within the EU. Google Workspace is listed as planned.[25]
- Migration risk and coexistence
- 5.0
- BEC the gateway misses
- 5.0
- Cost versus gateway renewal
- 3.0
- Microsoft 365 and Google Workspace coverage
- 4.0
- Internal mail and post-delivery remediation
- 6.0
- EU hosting and DPA transparency
- 9.0
- Gateway functions you keep
- 9.0
Pros
- German data centres documented.
- AI components operated within the EU, per Retarus.
- Full gateway feature set, or an API connector.
Cons
- No Google Workspace support yet.
- BEC handling not specifically documented.
- Quote-based pricing.
- Pricing
- Quote-based
- Deployment
- Secure email gateway (MX) or an API connector (ICES)
- Platforms
- Microsoft 365 (Google Workspace listed as "planned")
- Hosting
- Two German data centres, Munich (primary) and Frankfurt (peer), per Retarus documentation
Replace your secure email gateway, or sit behind it first?
A secure email gateway (SEG) is a filter your MX record points at: every inbound message passes through it before it reaches Microsoft 365, Google Workspace or an on-premises server. Email security gateway solutions were built when mail servers had little filtering of their own. In 2026 both Microsoft and Google filter bulk spam and malware natively, and Microsoft documents Defender for Office 365 Plan 1 rolling out to Microsoft 365 E3 and Office 365 E3 from June 2026. Many organizations now pay for two filtering layers.
Three ways to replace a gateway
| Path | What changes | What you keep | Fits |
|---|---|---|---|
| Native filtering plus an API layer | MX goes back to Microsoft or Google; the API tool stays connected throughout | Native spam and malware filtering; API detection for BEC and internal mail | Most Microsoft 365 and Google Workspace tenants |
| Gateway vendor’s API mode | Same supplier, API product instead of MX routing | Vendor relationship, archive and add-ons | Teams tied to Mimecast or Proofpoint extras |
| Another gateway | MX moves to a different gateway | Pre-delivery filtering, continuity, on-premises support | On-premises Exchange; strict German or private-cloud hosting |
A low-risk replacement plan
- Connect the API tool while the gateway is still in place. With Sentaro this takes four minutes and does not touch MX.
- Run both on live mail for two to four weeks and record what each caught and missed, including internal mail.
- List the gateway features you actually use: archive, continuity, outbound encryption, DLP rules, disclaimers. Map each one to Microsoft 365, Google Workspace or a separate tool.
- Turn on the native protections you already license (preset security policies in Defender, Gmail advanced phishing settings).
- Lower the MX TTL, move MX back to Microsoft or Google, and keep the gateway contract until the cutover is verified.
Questions to ask before you drop a gateway
- Which gateway features are in active use, and where will each live afterwards?
- Does the alternative act before the user can interact, or after delivery?
- Can it run in parallel with the gateway without changing mail flow?
- Does it see internal mail and historical mail from day one?
- Where is mail content processed, and who are the subprocessors?
- What does it cost per mailbox, compared with the gateway renewal?
For the architecture in depth, see API email security vs secure email gateway. For a broader shortlist, see our lists of the best email security software and the best cloud email security solutions.
Certification and compliance status
Sentaro’s status, stated exactly; we’ll update it the day each certificate is signed.
- SOC 2
- In progressNo target date published. Evidence pack on request.
- ISO 27001
- In progressNo target date published.
- Google CASA
- Verified API integration
- DPA and subprocessor list
- Public[4]
Frequently asked questions
What is the best secure email gateway alternative?
Sentaro, for EU organizations on Microsoft 365 and Google Workspace. It connects over API in four minutes with no MX change, so it can run behind your gateway before you retire it. It targets payload-free BEC and vendor compromise, scans internal mail, and costs $6 per protected account per month, first account free (prices in USD). Check Point Harmony, Abnormal AI and Barracuda follow on our method.
Is Sentaro a secure email gateway?
No. Sentaro is an integrated cloud email security (ICES) platform. It connects through the Microsoft 365 and Google Workspace APIs and runs behind native filtering instead of in front of your mail server, so your MX record does not change. It does not provide gateway extras such as archiving, continuity or outbound encryption.
Do I still need a secure email gateway with Microsoft 365?
Often not for filtering. Microsoft 365 includes built-in protection for every cloud mailbox, and Defender for Office 365 Plan 1 is included in Business Premium and rolling out to E3. Keep a gateway if you rely on its archiving, continuity, outbound encryption or on-premises Exchange support. Many teams replace it with native filtering plus an API layer for BEC.
What are the best secure email gateway providers in 2026?
If you want to keep a gateway, the established providers include Proofpoint, Mimecast, Cisco, Barracuda, Hornetsecurity, Libraesva and Retarus. For EU buyers, Retarus documents German data centres and Libraesva offers on-premises and private-cloud deployment. If you are replacing the gateway rather than renewing it, our ranking above puts Sentaro first.
What do I lose when I remove a secure email gateway?
Whatever the gateway did besides filtering: archiving, email continuity during outages, outbound encryption and DLP rules, disclaimers, and support for on-premises mail servers. Map each to Microsoft 365, Google Workspace or a separate tool before cutover. Filtering of bulk spam and malware continues natively.
Can an API-based tool run alongside our existing gateway?
Yes. API-based tools connect to the mailbox, not to mail flow, so they can run behind a gateway. That is the safest way to compare: run both on live mail, compare results, then decide. Sentaro says most customers retire the gateway later.
How long does it take to replace a secure email gateway?
The API side can be immediate: Sentaro connects in four minutes with historical visibility within 15 minutes. The MX cutover itself is a planned DNS change, usually after a parallel period of a few weeks and once gateway-only features such as archiving have a new home.
Sources and method
Sentaro publishes this list and ranks itself first; scores use the method above and public vendor documentation as of 21 October 2026. Product capabilities and prices change; check each vendor’s current documentation. Trademarks belong to their owners. Corrections: contact Sentaro.
- Sentaro pricing
- Sentaro: platform (deployment, Vord engine, vectors)
- Sentaro: customers (Nordic fintech case study)
- Sentaro Data Processing Agreement and subprocessor list
- Microsoft Learn: Why do I need Microsoft Defender for Office 365? (accessed 2026-10-18)
- Microsoft Learn: Built-in security features for all cloud mailboxes (EOP) (accessed 2026-10-18)
- Microsoft Tech Community: Defender for Office 365 Plan 1 rolling out to Microsoft 365 E3 (2026-06-17)
- Microsoft Learn: EU Data Boundary (accessed 2026-10-18)
- Check Point: Harmony Email & Collaboration (accessed 2026-10-18)
- Check Point: Harmony Email & Collaboration pricing tiers (accessed 2026-10-18)
- Check Point: Harmony Email & Collaboration admin guide, data residency
- Barracuda: Email Protection (accessed 2026-10-18)
- Barracuda: Email Protection plans (accessed 2026-10-18)
- Abnormal AI: Inbound Email Security (accessed 2026-10-18)
- Abnormal AI: Subprocessors (updated 31 July 2026, accessed 2026-10-21)
- Mimecast: Email Security (accessed 2026-10-18)
- Datacentre News: Mimecast opens two Frankfurt data centres (2018)
- Proofpoint: Core Email Protection (accessed 2026-10-18)
- Proofpoint: Core Email Protection API (accessed 2026-10-21)
- Cisco: Secure Email (accessed 2026-10-21)
- Cisco: Secure Email Threat Defense data sheet (accessed 2026-10-21)
- Libraesva: Home page (accessed 2026-10-18)
- Libraesva: Proofpoint vs Libraesva (deployment options)
- Retarus: Email Security (accessed 2026-10-18)
- Retarus docs: Email Security data center operations (Munich and Frankfurt)
- Barracuda Trust Center: Data center locations (accessed 2026-10-21)
- Proofpoint: Data privacy information sheet, Core Email Protection API (updated 24 July 2026; accessed 2026-10-21)