# Email security for enterprise buyers: what AI models recommend, October 2026

Gane Index, October 2026 Edition. Asked as "email security platform" and as "phishing and email threat protection tool", six framings each, to fourteen models with search on, on behalf of an enterprise B2B company. Page: https://www.gane.ai/index/it/security/email-security/2026-10/enterprise

This is the permanent record of the October 2026 Edition, published October 1, 2026 and superseded since. The current standing: https://www.gane.ai/index/it/security/email-security/enterprise/index.md

**Standing:** Proofpoint Email Protection leads with 48% of first choices; verdict clear leader. 52 first choices across the direct, paraphrase, budget and scale prompts.

## First-choice share

| Rank | Product | Share | Negative rate | Labels |
|---|---|---|---|---|
| 1 | [Proofpoint Email Protection](https://www.gane.ai/index/it/vendors/proofpoint-email-protection/index.md) | 48% | 10% | 71 |
| 2 | [Microsoft Defender for Office 365](https://www.gane.ai/index/it/vendors/microsoft-defender-for-office-365/index.md) | 29% | 4% | 55 |
| 3 | [Abnormal AI](https://www.gane.ai/index/it/vendors/abnormal-ai/index.md) | 10% | 6% | 47 |
| 4 | [Mimecast Email Security](https://www.gane.ai/index/it/vendors/mimecast-email-security/index.md) | 8% | 15% | 66 |
| 5 | [IRONSCALES](https://www.gane.ai/index/it/vendors/ironscales/index.md) | 2% | 0% | 15 |
| 8 | [Check Point Harmony Email & Collaboration](https://www.gane.ai/index/it/vendors/check-point-harmony-email-collaboration/index.md) | 0% | 8% | 25 |
| 9 | [Cisco Secure Email](https://www.gane.ai/index/it/vendors/cisco-secure-email/index.md) | 0% | 6% | 16 |
| 10 | [Barracuda Email Protection](https://www.gane.ai/index/it/vendors/barracuda-email-protection/index.md) | 0% | 25% | 20 |

Rank is by share of first choices among all 59 products named; products with the same share are tied, and the order among them carries no meaning. The table lists those with at least 10 labels.

## Each model's first choice on the direct prompt

- Claude Haiku 4.5: no first choice
- GPT-5.4 mini: Proofpoint Email Protection; alternatives Microsoft Defender for Office 365, Mimecast Email Security
- Gemini 3.5 Flash: Abnormal AI; alternatives Check Point Harmony Email & Collaboration, Microsoft Defender for Office 365, Mimecast Email Security, Proofpoint Email Protection
- Perplexity Sonar: Proofpoint Email Protection; alternatives Check Point Harmony Email & Collaboration, Mimecast Email Security
- Grok 4.20: Mimecast Email Security, Proofpoint Email Protection; alternatives Abnormal AI, Check Point Harmony Email & Collaboration, Egress, Microsoft Defender for Office 365
- Mistral Small: Abnormal AI, Proofpoint Email Protection; alternatives Cloudflare Email Security, Mimecast Email Security
- DeepSeek V4 Flash: Proofpoint Email Protection; alternatives Abnormal AI, Microsoft Defender for Office 365, Mimecast Email Security
- Llama 4 Maverick: IRONSCALES; alternatives Abnormal AI, Barracuda Email Protection, Check Point Harmony Email & Collaboration, Microsoft Defender for Office 365
- Qwen 3.7 Flash: Proofpoint Email Protection; alternatives Check Point Harmony Email & Collaboration, KnowBe4
- Kimi K2: Proofpoint Email Protection; alternatives Abnormal AI, Microsoft Defender for Office 365, Mimecast Email Security
- GLM 4.7 FlashX: Mimecast Email Security, Proofpoint Email Protection; alternatives Barracuda Email Protection
- MiniMax M2.5: Mimecast Email Security, Proofpoint Email Protection; alternatives Microsoft Defender for Office 365, Perception Point
- GPT-6 Luna: Proofpoint Email Protection; alternatives Abnormal AI, Microsoft Defender for Office 365, Mimecast Email Security
- Muse Glimmer 30B: Proofpoint Email Protection; alternatives Check Point Harmony Email & Collaboration, Microsoft Defender for Office 365, Mimecast Email Security

## Sources the answers cite

79 of 84 answers came back with a source list, from 14 of 14 models. Sites named in the most answers:

- proofpoint.com: 40 answers, 64 citations
- expertinsights.com: 32 answers, 44 citations
- sublime.security: 32 answers, 41 citations
- gartner.com: 31 answers, 39 citations
- huntress.com: 30 answers, 34 citations
- checkpoint.com: 28 answers, 42 citations
- kaseya.com: 27 answers, 28 citations
- comparitech.com: 27 answers, 27 citations

Pages named in the most answers:

- https://kaseya.com/blog/best-email-security-solutions (27 answers)
- https://gartner.com/reviews/market/email-security (26 answers)
- https://proofpoint.com/us/industry-comparison/email-security (26 answers)
- https://comparitech.com/net-admin/email-security (24 answers)
- https://huntress.com/business-email-compromise-guide/10-best-email-security-providers (23 answers)
- https://ironscales.com/blog/the-best-email-security-companies-rankings-and-reviews (20 answers)
- https://sublime.security/articles/enterprise-email-security-solutions (20 answers)
- https://bcs365.com/insights/best-email-security-solutions-gartner (18 answers)
- https://cio.economictimes.indiatimes.com/tools/best-email-security-tools/127801326 (15 answers)
- https://expertinsights.com/email-security/top-email-security-gateways (15 answers)

## Warned against

- Mimecast Email Security: 10 of 66 labels negative. "Do not buy another traditional Gateway (like Proofpoint or Mimecast)." (Gemini 3.5 Flash, paraphrase prompt)
- Proofpoint Email Protection: 7 of 71 labels negative. "Legacy Secure Email Gateways (like Mimecast or Proofpoint) are notoriously complex. They often charge extra for essential features" (Gemini 3.5 Flash, budget prompt)
- Barracuda Email Protection: 5 of 20 labels negative. "Barracuda announced any ESG appliance that had been compromised must be taken out of service and disposed of; patching was insufficient." (Muse Glimmer 30B, negative prompt)
- Barracuda Email Security Gateway: 3 of 3 labels negative. "Large enterprises should avoid or exercise extreme caution with Barracuda Email Security Gateway due to its recent critical vulnerabilities and ongoing exploitation." (Mistral Small, negative prompt)

## Movement since September 2026

Floor: 11 points of share, measured on the calibration repeat.
Same leader: Proofpoint Email Protection at 48%.

- Proofpoint Email Protection: 40% to 48%, +8. Inside the floor by 3 points · rank 1 of 56, unchanged.
- Microsoft Defender for Office 365: 38% to 30%, −8. Inside the floor by 3 points · rank 2 of 56, unchanged.
- Mimecast Email Security: 2% to 9%, +7. Inside the floor by 4 points · rank 4 of 56, unchanged.
- IRONSCALES: 0% to 2%, +2. Inside the floor by 9 points · rank 10 → 5 of 56.
- Abnormal AI: 10% to 11%, +1. Inside the floor by 10 points · rank 3 of 56, unchanged.
- Check Point Harmony Email & Collaboration: 0% to 0%, ±0. Inside the floor by 11 points · rank 9 → 6 of 56.
- Cisco Secure Email: 0% to 0%, ±0. Inside the floor by 11 points · rank 25 → 7 of 56.
- Barracuda Email Protection: 0% to 0%, ±0. Inside the floor by 11 points · rank 24 → 8 of 56.
- Sublime Security: 0% to 0%, ±0. Inside the floor by 11 points · rank 11 of 56, unchanged.

## Record

- Method: https://www.gane.ai/index/it/methodology
- License: CC BY 4.0. Cite as Gane Index, October 2026 Edition, www.gane.ai/index/it.